Horst Bremer Neto1
Simone Rodrigues da Silva2
Francisco de Assis Alves Mourão Filho3
Marcel Bellato Sposito4
Marina Maitto Caputo5
1 Agronomist, PhD. Crop Science Department, College of Agriculture Luiz de Queiroz/
University of São Paulo. Email:firstname.lastname@example.org
2 Associated Professor, Crop Science Department, College of Agriculture Luiz de Queiroz/
University of São Paulo. Email:email@example.com
3 Associated Professor, Crop Science Department, College of Agriculture Luiz de Queiroz/
University of São Paulo. Email:firstname.lastname@example.org
4 Associated Professor, Crop Science Department, College of Agriculture Luiz de Queiroz/
University of São Paulo. Email: email@example.com.
5 Agronomist, PhD. Email:firstname.lastname@example.org
Dados Internacionais de Catalogação na Publicação
DIVISÃO DE BIBLIOTECA - DIBD/ESALQ/USP
The citrus nursery practices in Brazil [recurso eletrônico] / Horst Bremer Neto … [et al.]. - -
Araraquara: Vivecitrus Organização Paulista de Viveiros de Mudas Cítricas, 2016.
69 p. (pen drive)
1. Brasil 2. Citricultura 3. Frutas cítricas 4. Mudas 5. Viveiros I. Bremer Neto, H. II. Silva, S.
R. da III. Mourão Filho, F. de A. A. IV. Sposito, M. B. V. Caputo, M. M. VI. Título
The Citrus Nursery Practices in Brazil 3
Agromillora P e C de Mudas Vegetais Ltda
Citros Salva Mudas Cítricas Ltda
Citrosuco S/A Agroindústria
Sucocítrico Cutrale Ltda
Terral Agricultura e Pecuária S/A
Viveiro dos Laranjais Agropecuária Ltda
The exchange of information, of good or bad experiences, contributes to the
improvement of people, processes and products.
The purpose of contributing to improve the Citriculture by means of its base,
“citrus nursery tree”, a group of citrus nurseries founded in October, 1988,
‘Associação Paulista de Viveiros Certificados de Citros’, currently referred to as
‘Paulista de Viveiros de Mudas Citrícas’ (Vivecitrus), located in Araraquara, State of
During the 15 years of its existence, the Vivecitrus and its members contributed in
establishing citrus nursery tree production quality standards and methodologies,
according to the rules of the Sanitary Plant Protection of the Office of Agriculture
and Supply of São Paulo, contributing to generate healthy orchards. Within its
technical purpose, Vivecitrus often holds meetings with researchers and Brazilian
and foreign technicians for discussion and preparation of pilot projects related to
irrigation, nutrition, prevention and control of pests and diseases.
Since 1999, Vivecitrus arranges the Nursery Growers Day, since 2010, the
Management Meetings to Production Citrus Nursery tree, held at, respectively, Sylvio
Moreira/IAC Citriculture Center and at Citriculture Experimental Station of
Bebedouro. It quarterly publishes the Vivecitrus informative, as well as it maintains
the website www.vivecitrus.com.br, which is focused on current topics of citrus
Its members actively attended the preparation of Rules for Production of
Certification Nursery Tree in Protected Environment, as well as they worked in the
preparation of funding rules for construction to protected structures in the citrus
nurseries and in the preparation of insurance against citrus canker and weather
Aiming to share the knowledge acquired during 15 years of professionalism, the
members of Vivecitrus presented to guide The Citrus Nursery Practices in Brazil to
the citrus community, which included orientations about the best method to
The Citrus Nursery Practices in Brazil 5
produce citrus nursery tree, according to current legislation. The guide encompasses
infrastructure guidelines necessary to install the nursery, features of main scions and
rootstocks, stages of citrus nursery production, irrigation, fertilization, pests and
diseases control and production costs.
However, our proposed to intensify the exchange of ideas and promote
constructive disagreements that will contribute to the improvement of "the
keystone of citrus”: citrus nursery tree.
Jorgino Pompeu Junior, PhD.
To the citrus nurseries grower’s members of Vivecitrus by the shared knowledge
throughout the preparation of this paper.
To the Ministry of Agriculture, Livestock and Food Supply and Office of Agriculture
and Food Supply of the State of São Paulo for the information related to standards of
the citrus nursery tree production.
To Agronomist Vitor José Betin Cicolin and employees of Horticitrus for the shared
To Heraldo Negri de Oliveira, Ricardo Krauss and Otavio Ricardo Sempionato for
images involving pests, control disease and production of citrus nursery tree in open
To Agronomist Leandro Fukuda for the information involving technical of
production of citrus nurseries trees within protected environment.
The Citrus Nursery Practices in Brazil 7
Preface ................................................................................................................................. 4
Acknowledgements ........................................................................................................ 6
1. Introduction ............................................................................................................... 9
2. Regulating Requirements ......................................................................................... 11
3. Nursery installation .................................................................................................. 14
3.1 Area ........................................................................................................................... 14
3.2 Infrastructure ............................................................................................................... 15
3.2.1 Nursery and budwoods ....................................................................................... 15
3.2.2 Mother Nursery ................................................................................................... 18
4. Stages for production of citrus nursery .................................................................... 20
4.1 Rootstocks prodution................................................................................................... 20
4.2 Production, harvest, processing and storage of budwoods ........................................ 27
4.3 Formation of citrus nursery tree .................................................................................. 28
5. Irrigation .................................................................................................................. 33
6. Fertilization .............................................................................................................. 36
7. Nursery Pests and Diseases ...................................................................................... 39
7.1 Important citrus diseases spread by citrus nursery plants .......................................... 40
7.1.1 Tristeza disease and Citrus Sudden Death (CSD) ................................................ 40
7.1.2 Citrus canker ...................................................................................................... 41
7.1.3 Citrus variegated chlorosis and Huanglongbing ................................................. 42
7.1.4 Citrus black spot ................................................................................................. 44
7.2 Main pests in nurseries ................................................................................................ 45
7.3 Control of pests and diseases in nurseries ................................................................... 50
8. Weeds ...................................................................................................................... 54
9. Scions and rootstocks ............................................................................................... 55
9.1 Rootstocks .................................................................................................................... 55
9.2 Scions ........................................................................................................................... 57
10. Production Costs .................................................................................................... 62
Bibliography ................................................................................................................. 66
Anexx 1 .............................................................................................................................. 67
Anexx 2 .............................................................................................................................. 69
The Citrus Nursery Practices in Brazil 10
The first reports regarding the citrus crop in Brazil are from the sixteenth century,
in the States of São Paulo, Bahia and Rio Grande do Sul. From its introduction to the
recognition of the advantages associated with grafting, in the early twentieth
century, the multiplication of citrus was made by seeds, originating non-grafted
plants, with many thorns and beginning of delayed production due to the long period
of juvenility of plants obtained by this method. The production of grafted plants
enabled the size reduction plants, few thorns and early production. In addition to
these advantages, the grafting enabled the production of clones, genetically identical
plants, better adaptation to different environments and production systems and
disease tolerance, through the proper selection of the rootstock, which attracted the
interest of growers. For these reasons, vegetative propagation, by bud grafting of
scion varieties of commercial interest in selected rootstocks, was established as the
main method of commercial multiplication of citrus plants in the world. The use of
bud grafting or budding, however, may present risks related to the spread of viruses,
viroid, bacteria transmitted mechanically and/or insect vectors, considering that
preventative control measures are not taken. In addition, the production of
rootstocks and citrus nursery trees can be affected by pathogens that are spread by
the wind, substrate, irrigation water and clothing, such as citrus canker, nematodes,
gummosis caused by Phytophthora, among others.
It is worth to note that many of the diseases that occur in nurseries have a long
incubation period, with symptoms that manifest themselves long after the infection,
not only compromising the health of citrus plant nurseries, but the entire investment
made in the formation of a new orchard. The increasing of diversity and complexity
of diseases affect citrus production in Brazil, the care needed for the production of
basic propagating material and citrus nursery tree have become priority.
In the 1990s, with the report of Citrus Variegated Chlorosis (CVC), a disease
caused by the bacterium Xylella fastidiosa, important changes occurred in the
citrus plants nurseries production system, which until then were produced in the
open field (Figure 1a). The discovery of the transmission of bacteria by insect
vectors (Leafhopper) led the Office of Agriculture and Food Supply of São Paulo,
from 1999, to publish Ordinances aiming at health of basic propagation material
and São Paulo citrus nursery tree. These Ordinances induced significant changes in
the production system, such as the obligatory production of budwoods and citrus
nursery tree in a protected environment (Figure 1b). Thus, all the knowledge
involving the selection of location, facilities, equipment, inputs and budstocks,
rootstock and citrus nursery tree production techniques held in open field
production system needed to be adjusted to new legal requirements.
This guide is a summary of knowledge produced and consolidated by the efforts
of technicians, researchers and citrus nurseries that, since 1998, dedicated
themselves to activity of citrus nurseries trees production in a protected
Figure 1 Production of citrus nursery tree in open field (a) and in protected environment (b).
Photo: Otávio Sempionato and (b)Vivecitrus.
The Citrus Nursery practices in Brazil………………11
2. Regulating Requirements
The legislation that regulates the production of citrus nursery tree aims to
ensure quality, health and genetic purity of the material multiplied and traded
in Brazil. The technical and operational requirements are high and the nursery
grower must be aware of each one of them, including the preparation of the
technical project and in all other stages of production, under penalty of having
of the nursery interdicted or have the sale of citrus nursery tree suspended. In
general, federal law concerns, predominantly, aspects related to ensuring the
genetic, horticultural and standardization quality of propagating material
traded, while the laws of the State of São Paulo, in addition to such,
encompasses phytosanitary aspects of production.
According to the standards established by the federal law, both individuals
and legal entities engaged in the activities of production, processing, packaging,
storage, analysis, trade, import and export of seeds and plant nurseries must
be mandatorily enrolled with National Registry for Seeds and Seedlings
(RENASEM) of Ministry of Agriculture, Livestock and Food Supply (MAPA), as
well as having all the implementation stages of nursery and production of
seedlin monitored by responsible technician, also accredited by MAPA.
Moreover, all cultivars used as scions and rootstock must be previously
qualified by the National Registry of Cultivars (RNC) of MAPA. The RNC ensures
that the cultivars available to farmers were evaluated by Brazilian institutions
and present the latest research advances in genetics and plant breeding. The
list of cultivars qualified by RNC is available in the website
(www.agricultura.gov.br/vegetal/sementes-mudas). Also at the federal level,
the producer of citrus propagating material must be aware of the Normative
Instruction No. 48 of the MAPA (IN 48), issued on September 24, 2013,
providing rules for the production and trade of citrus propagating material and
its hybrids, valid throughout national territory. According to IN 48, all
production activities, including seed, budwoods and citrus nursery tree
production must be enrolled with and inspected by MAPA, respecting terms,
rules and specific technical requirements of each stage of production.
In the State of São Paulo, in addition to enrollment with MAPA, the grower
and nursery growers of citrus nursery trees must be registered in the
Department of Agriculture and Livestock Protection of the Agriculture and Food
Supply Office (CDA). This registration involves basic information about the
growers and infrastructure report of production place, used in phytosanitary
inspection, control of the regulatory requirements of production and issuance
of Plant Transit Permit Guide (PTV), required for the trade of citrus nursery
trees. This registration must be prepared by the Agricultural Engineer qualified
by the Regional Council of Engineering, Architecture and Agronomy (CREA), and
must be renewed every three years. The legislation in the State of São Paulo
requires that the production of rootstocks, budwoods and citrus nursery trees
are carried out in an appropriate place, intended solely for the production of
citrus nursery trees and protected by antiophidic screen (against aphids input
and leafhoppers) and through the use of seeds and budwoods obtained by
matrix plants and budstocks recorded in CDA.
After the registrations in MAPA and CDA, the growers shall submit, to CDA,
the technical level of production of citrus nursery trees, prepared by the
Agricultural Engineer in charge for the nursery, stating the amount of citrus
nursery tree, cultivars, scions and rootstock used and the production period, up
to 15 days after sowing or transplanting of rootstocks, where they are
purchased from third parties. Through the registration of the technical plan of
production, CDA is able to inspect all production stage.
Throughout the production period, the technician in charge for the nursery
must issue three phytosanitary reports. Such report of first inspection must be
issued up to 15 days after sowing or transplanting of rootstock, if such is obtained
from third parties, informing the material origin, as well as the sowed or
transplanted amount. The phytosanitary report of second inspection must be
issued in the grafting and inform the grow crops that will be used as scions, the
amount of grafting, as well as the origin of budwoods. The phytosanitary report
of third inspection will be issued in the release of the seedlings and buds will
contain the results of health tests that prove the absence of CVC, gummosis of
Phytophthora, huanglongbing (ex-greening, HLB) and nematodes, in addition to
information about other phytosanitary events. It is worth to note that laboratory
tests should be carried out in laboratories accredited by MAPA and registered in
the CDA. In addition to these reports, it is necessary to submit a final report that
should inform the total production, seedlings destination and other information
required by the CDA, ending the activities of the technical production plan. Like
the nursery, the budwoods requires registration with the CDA, infrastructure
report and formation plan issued by the technician in charge. Thus, along the bud
grafting useful life, it shall also be issued inspection reports and inspection of bud
The Citrus Nursery practices in Brazil………………13
grafting. The first report is issued at sowing or transplanting rootstock, stating
the origin of the seed or budstocks; the second report, at the time of grafting,
proving farming and source of budstocks to be used as scions, and the third
report of inspection, in release of budwoods. Semiannually, budstocks should be
subjected to inspection by CDA inspector and, annually, laboratory tests proving
the health of plants (in relation to CVC and HLB or when found the presence of
symptomatic plants) should be made for its intended use by nursery gardener
and/or trading. After five years, counted from the grafting of plants of bud
grafting, it should be discarded in the presence of CDA inspector.
Detailed information about legal matters of production of seedling may be
obtained in Law 10.711/2003, Decree 5153/2004, Federal Normative Instruction
N.9/2005,24/2005,42/2009,2/2010 and 48/2013,and in State Ordinances N. 5 and 23.
It is worth to note that the legislation governing the activity of seedling
production can be modified, aiming its adaptation to the industry needs, leaving
the nursery growers and technicians the responsibility to be updated with any
changes in production standards. To this end, it is recommended often access the
website of CDA (www.cda.sp.gov.br) and of MAPA (www.agricultura.gov.br).In
Annex 1 is included a list of records, licenses and other documents required by
law and applicable to the production of seeds and citrus nursery tree in the
federal and state levels.
3. Nursery installation
The selection of the area where the source citrus tree bud and the citrus nursery
will be installed is the first step for the health of the citrus nursery tree to be
protected. In this respect, the main factor to be evaluated is the distance between
the area intended for installation and commercial or domestic citrus orchards.
According to legislation governing the activity in the State of São Paulo (Ordinance
N. 05 of CDA), the distance between nursery and other citrus plants must be, at
lease, 20 meters (Figure 3.1a). When focus of citrus canker is registered in a period
less than two years in orchards nearby nursery installation area, this must be
installed at a minimum distance of 1200 m. Hedges of ornamental plants such as
myrtle (Murraya paniculata) should also be avoided, as are alternative diseases
affecting citrus host, such as bacteria associated with HLB
The place where the nursery will be installed should present soil and relief that
promote the drainage of rainwater, preventing the accumulation of water and
possible spread of soil-borne pathogens. It is also important to observe the
prevailing conditions, particularly the temperature of the air, for both low
temperatures as high, may compromise the formation of changes. Thus, one can
anticipate the need for additional devices in nurseries for maintaining the proper
temperature for the growth of citrus nursery tree. When the purpose is to reduce
the air temperature, may be used netted shade or woven meshes.
Figure 3.1 Nursery of production of citrus nursery plants insulated from commercial citrus
orchards(a) and greenhouse equipped with woven meshes to control solar radiation and
internal temperature (b). Photos: (a) Vivecitrus and (b) Horst Bremer Neto.
The Citrus Nursery practices in Brazil………………15
(Figure 3.1b). In order to maintain higher temperatures, curt insider may be used.
Another important aspect in the implementation of the citrus nursery is enough
water available to meet the demand of irrigation plants throughout all stages of
production and sanitation of the nursery. When the water is taken from rivers, lakes
and dams, its treatment is mandatory, aiming to reduce the risks of biological
contamination. When water is extracted from artesian wells, a sanitary treatment is
not necessary. Regardless of the source of water for irrigation. the acceptable limits of
concentration of salts must be respected in order to prevent salinization of the
substrate and not jeopardize the proper growth of citrus nursery tree.
3.2.1 Nursery and budwoods
According to Ordinance N. 05 of CDA, the physical structure and basic equipment for
installation of greenhouse will compose nurseries and bud grafting include woven meshes
(maximum of 0.87 x 0.30 mm), without hole or cracks; waterproof cover, without holes or
cracks (usually used in a transparent polyethylene film with a thickness of 150 µm);
antechamber with minimum area of 4 m2, to reduce the risk of entry of insect vectors,
with footbaths for disinfection of footwear and container for disinfection of hands and
utensils containing chlorhexidine digluconate (Figures 3.2a, b, c, d); countertops, installed
40 cm above ground level in order to avoid the contact of the root system of young citrus
tree with the floor and prevent possible infection by Phytophthora and nematodes;
Figure 3.2 Antechamber in nursery and protected environment for Antiophidic screen and
waterproof cover (a), footbath (b,c) and reservoir for disinfection of hands and
utensils(d).Photos: Horst Bremer Neto.
spaces between the countertop with the floor or with crushed stone layer, or
similar, with, at least, 5cm thick (Figure 3.3a; b; c) and side short wall along the
entire perimeter of the greenhouse to prevent invasive water entry (Figure3.4a).
Although allowed, it is not recommended to use crushed stone for paving of the
nursery, since this material may favor the incidence of weeds and hinder cleaning
of the nursery. In this case, the nursery growers should give preference to concrete
pavements or raffia (Figure 3.3a; b). Countertops can be made of wood (not
recommended for hindering cleaning and disinfection), iron or masonry, using
blocks, beams and precast grids (Figure 3.3a; b). At the federal level, the
requirements of IN 48 are smaller in relation to the laws of the State of São Paulo,
limited to the coverage with antiophidic screen, antechamber and hand washing
devices for the production of bud grafting and certified citrus nursery tree.
The quality and strength of the materials used in the greenhouse structure cover
are essential to reduce the risk of breakage of the screen, avoiding the entry of
vector insects and pathogens. The use of windbreak composed by high species
reduces the wind speed by protecting the structure of the greenhouse, besides
acting as a physical barrier against pathogens, insect vectors and solid particles
which may be adhered to the side screens and the greenhouse cover reducing the
brightness (Figure 3.4b). It is recommended that the right foot of the greenhouse
presents a minimum height of 4 m, enough to promote adequate air circulation,
reducing the occurrence of high temperatures. The internal area must be free of
pest plants, the carrier between the countertops and the screen
Figure 3.3 Bench consisting of grids and concrete blocks on raffia floor (a) e
b) and corridor paved with concrete (c). Photos: Horst Bremer Neto.
The Citrus Nursery practices in Brazil………………17
and between countertop must present minimum distance of 50 cm and the outer
perimeter of the greenhouse should be free of vegetation in a minimum range of
1 m. The place destined for the storage and handling of the substrate should be
paved and free of invasive water.
The greenhouse used for the production of budsticks shall be used solely for
this purpose. The production structure should have waterproof plastic cover and
side closure antiophidic screen (maximum mesh 0.87 x 0.30 mm), antechamber,
footbath, among others, with the same specifications applied to greenhouses
that will produce the citrus nursery tree. It is worth to note that under the plastic
cover, the installation of antiophidic screen is obligatory. The right foot should
provide minimum height of 4 m and a distance between the side screen and the
plants should be at least 1 m. The plants can be grown directly on the ground
(floor) or vessels containing substrate, suspended in countertop (Figure 3.5). The
renewal of budwoods cultivated the ground presents difficulties related to the
elimination of crop residues, especially the root system and may compromise the
health of the plants of the new planting. On the other hand, the budwoods grown
in pots, even though they have higher costs and require greater care in the
management of irrigation and nutrition, are easy to be renewed and for this
reason the bud grafting production system is most widely used. In this system,
bags with capacity from 3 to 20 L of substrate are used, depending on the
conduction system of the plants.
In addition to the care mentioned, vehicle and person access control in the
nursery, and especially within the production greenhouses, is essential to
practice safety and phytosanitary guarantee the production of budwoods,
rootstock and citrus nursery tree.
Figure 3.4 Greenhouse production of citrus nursery tree containing side short wall and
rainwater conduction system (a) and windbreak of Casuarina (Casuarina equisetifolia) (b).
Photos: (a) Simone R. Silva and (b) Horst Bremer Neto.
Figure 3.5 Budding of citrus grown in bags of 7 liters on countertop. Photo: Horst Bremer
Thus, it is recommended that the vehicle traffic is restricted. Vehicles should not
have access to production greenhouses. Also, it is recommended that a wheel
disinfection facility is installed for the disinfestation of vehicles that will need to
move in the nursery. Unauthorized persons shall not have access to nursery.
Additionally, it is recommended that the nurseryman provides uniforms to
employees who perform activities within the greenhouse, ensuring at least two
shifts per week. The uniforms should be washed in the very facilities of nursery or
specialized companies, under the responsibility of nursery gardener. Discarded
substrate, seedlings and debris cannot be stored inside the greenhouse and must
be deposited in an independent environment to incineration or sent to sanitary
3.2.2 Mother Nursery
The structure used for phytosanitary protection of stock plants of cultivars used
as scions should be composed of structure resistant to strong winds and the
greenhouse should be aphid-proof, providing protection against vectors of CVC,
HLB and Citrus Sudden Death (CSD). The structure can be protected by screen or
by screen association of plastic coating, provided that the latter reduces the leaves
wetting and risk of occurrence of citrus canker and of black spot.
The Citrus Nursery practices in Brazil………………19
The height of the greenhouse should be more than 4 meters, to facilitate air
circulation and avoid problems resulting from high temperatures. It is important
to note that only the physical protection of the stock plant is not enough to keep
the sanity of it. Other measures should be adopted, such as the strict control of
the transit of persons, disinfestations in footwear, equipment, tools and clothing,
use of traps, inspections and preventive sprays to control insect vectors and fungal
diseases. At the federal level, according to IN 48, basic and stock plants should be
kept in a protected environment, which should contain antiophidic screen,
antechamber and device for hand washing.
The stock plants used to obtain seeds, aiming at the production of rootstocks,
can be grown in the open air under appropriate control disease, since diseases
such as CVC, HLB, Citrus Sudden Death (CSD), tristeza
and decline are not
transmitted by seeds, even when the stock plant is contaminated. The stock plants,
however, that are suspected or proven carriers of these diseases should not be
used for this purpose.
[tristeza: Citrus tristeza virus (CTV) is a viral species of the Closterovirus genus that causes the
most economically damaging disease to its namesake plant genus, Citrus. The disease has led to
the death of millions of Citrus trees all over the world and has rendered other millions useless for
4. Stages for production of citrus nursery
Commercial production citrus nursery tree consists of two distinct parts of citrus plants.
The rootstock, or stock, comprises the root system and lower stem or trunk. It usually grown
from seed. The upper part of the tree, consisting of the limbs, leaves and fruit, is known as
the scion. The scion is derived by inserting tissue, it is a bud. (Bud of the desired cultivar into
the rootstock in such a way that it unites with the rootstock and develops the fruiting).
Rootstock is the root system of the budded plant. The development of buds and rootstock
will result in the formation of the new plant scion and root system, respectively. By this
method, is possible to achieve the combination scion/rootstock that combines desirable
characteristics such as plant adaptation to various soil conditions, climate, disease and
production systems, enabling high fruit production with the desired quality. Moreover,
obtaining rootstocks by seed and grafting and bud grafting enables the formation of uniform
plants, with reduced production and early bearing. In Annex 2, it is presented a flowchart
showing the main steps and processes involved in the production of citrus nursery tree
4.1 Rootstocks production
The production of citrus nursery tree is obtained fruit removed from fruit produced in
registered stock plants. The harvest of fruit for the removal of the seed shall be carried out
in full ripening of fruits. It must be avoided the fruit from the ground and those located in
the canopy of the base, close to the ground, avoiding possible contamination by
Phytophthora spp. and other pathogens that compromise the storage of seeds and
development of rootstocks.
The extraction of seeds from fruits may be performed manually or mechanically. The
mechanical method has higher yields and can be conducted with corn thresher or sugarcane
chopper, containing toothed blades instead of knives. After extraction, the seeds must
undergo chemical treatment to the removal of mucilage (slime substance adhered to the
outer integument) and of the outer integument, popularly called "shell"(Figure 4.1a). The
mucilage should be performed right after the seed extraction, immersing the seeds solution
containing hydrated lime (0.5%) for approximately 10 minutes. Then, the seeds are washed
in water and subjected to heat treatment for 10 minutes in water at 52°C (Figure 4.1b),
The Citrus Nursery Practices in Brazil 21
15 ml of caustic soda (NaOH) and 3 ml of hydrochloric acid per liter of seeds. The
solution containing the seeds must be moved every 15 minutes for 45 minutes.
Later, the seeds should be washed under running water (Figure 4.1d) and subjected
to further treatment, in solution containing 100 g of hydrated lime, aiming to
remove chemical residues. Again, washing is made in running water, keeping the
seeds in a container containing water for manual removal of the integument
(rubbing the seeds between the hands) (Figure 4.1e).
Another procedure may also be adopted aiming at the removal of the outer
integument after removal of the mucilage and heat treatment such as immersion
of 3 kg of seeds in 6 L of water at a temperature between 35-37°C and pH between
11.5 and 12
. After the pH control, 3L of sodium hypochlorite is
(NaClO,10%). The solution containing the seeds must be stirred, by hand or
mechanically, every 15-30 minutes, verifying the time that the integument begins
to detach from the seed. When the integument starts to detach, treatment should
be stopped and the seeds washed immediately. After washing, rub the seeds
between your hands until the complete detachment of the integument. The
separation of the loose integument seed can be carried out after partial drying of
the material by means of blowers. It is worth to note that the treatment time varies
among cultivars and maturation stages of seeds. Seeds of more acidic fruit,
typically require more time. Younger seeds require less time, but are more
susceptible to chemical and mechanical damage during processing.
It is not recommended seed storage after removal of the seed coat, because its
removal may promote germination. Thus, the integument must be removed from
seeds that will be promptly used or stored for up to 10 days. If stored without
external integument, the seeds should be kept in plastic bags under 4°C. Seeds with
integument can be stored in cold chamber (Figure 4.1f), for a period exceeding six
months under temperature and relative humidity maintained between 6 and 8ºC
and 60 and 80%, respectively.
The pH of the solution is adjusted with caustic soda (NaOH).
The pH adjustment is necessary because sodium hypochlorite (NaClO) in solution with pH values equal to or lower
than 7 can kill the embryos.
The loss of germination power during the storage period is variable depending on
the type of the rootstock.
According to IN 48, the minimum standards for trading citrus seeds with genetic
origin evidence are: 98% purity, 50% germination, absence of inert materials and
maximum presence of other seeds of 0.05% and 0 07% when obtained from stock
plants and clonal garden, respectively. When derived from plant base, the
presence of other seeds should be zero.
Figure 4.1 Citrus seed with outer integument (left), with partially removed outer
integument (center) and without outer integument (right) (a); seed under thermal
treatment (b); application of a caustic soda in the solution (c); seeds washing (d); removal
of the outer integument (e); citrus seeds stored in cold chamber (f). Photos: Horst Bremer
The Citrus Nursery Practices in Brazil 23
The sowing is done in substratum packed in small plastic tubes. The plastic tube
volume should present between 50 and 70 ml and contain longitudinal grooves to
prevent entrapment of the root system (Figure 4.2a). The plastic tubes should be
placed in wire mesh divided into individual spaces for each plastic tube or trays in
continuous and suspended countertop in the approximate height of 1.5 m to
prevent contact of the root system with the greenhouse floor (Figures 4.2b; c).
The number of seeds per tube is set depending on the quality of seeds and
rootstock, ranging from one to four seeds. Species presenting greater
polyembryony rate (when more than one seedling germinates from the same
seed) (Figure 4.3a) require fewer seeds, given the greater likelihood of nucellars
.In this case, it uses one or two seeds in each. On the other hand, the
‘Rangpur’ (Citrus limonia Osbeck), due to lower polyembryony rate, requires more
seeds, three or four. ‘Swingle’ [Citrus. paradisi Macf. × Poncirus trifoliata (L.) Raf.]
requires two or three seeds per plastic tube. More seeds should be adopted when
the batch of those have low quality (smaller seeds with low germination rate).
Seeds should be arranged in the horizontal position or with the apex facing down
(Figure 4.3b), otherwise it increases the percentage of seedlings with defective
Figure 4.2 Plastic tube for citrus rootstocks production containing lateral grooves (a) and
suspended countertops containing trays for supporting plastic tubes (b; c). Photos: Horst
The embryos originate nucellar plants of interest for the production of rootstocks, as they are genetically identical to the
mother plant (clone), showing surely typical and desirable characteristics of the species. Plants from these embryos are
called popularly "female". In the nucellar embryo, the seed may contain zygotic embryos originating from plants with
unknown characteristics. Since they are not identical to the mother plant, it should be discarded.
24 Bremer Neto, H.; Silva S.R.; Mourão Filho, F.A.A.; Sposito M.B. & Caputo, M.M.
a b c
Figure 4.3 Emergence of two seed seedling of polyembryony species (a) provision of seeds
in the cartridge (b) and seeds of Swingle (CS) and Rangpur (LC) (c). Photos: Horst Bremer
The depth of sowing is variable depending on the rootstock and the size of
the seed. ‘Swingle’ citrumelo seeds presenting larger size in relation to the other
rootstocks (Figure 4.3c) can be seeded up to 2.5 cm in depth, while for the other
rootstock cultivars, sowing depth should not exceed 1.0 cm. The substrate should
provide retention capacity and adequate water drainage, allowing the plant to have
its water requirement provided without oxygenation of the root system is
compromised and still provide physical conditions conducive to the growth of the
root system. Moreover, according to law federal (IN 48) and São Paulo State
(Ordinance CDA in 5) laws, the substrate may not contain soil and should be free of
nematodes and pathogens, mainly Phythophtora spp., causal agent of gummosis,
not contain seeds or propagules of pest plant. In general, commercial substrates
are used consisting of Pine bark, coconut fiber, vermiculite or organic material,
usually charcoal (Figure 4.4a). The handling of the substrate must be carried out in
clean place, without contact with the ground to prevent contamination (Figure
Citrus Seeds emergence occurs between 15 and 45 days after sowing, due to
the environmental and species conditions. Up to 15 days after sowing, the
technician in charge for the nursery needs to deliver to CDA the production plan
and the plant report of first inspection (Anexx 1). About three or four months after
sowing, it shall be selected the most vigorous plants with typical characteristics of
the species, discarding non true-to-type and less vigorous plants. In Figure 4.5 it is
presented the examples of hybrid plants of Rangpur (Figures 4.5d, f) and ‘Swingle’
(Figure 4.5a) and plants with typical features of these species (Figures 4.5b, e). In
Figure 4.5c, it is possible to note ‘Swingle’ with greater and lower effective. In this
case, the plant with less force must be discarded.
The citrus Nursery Practices in Brazil……………… 25
Figure4.4Substrates used in commercial production of rootstocks and citrus nursery tree
compose of Pine bark (left) and coconut fiber (right)(a) and handling of the substrate to fill
the tubes in countertop(b). Photos: Horst Bremer Neto.
Figure 4.5 Examples of hybrid plants of ‘Swingle’ citrumelo (a) and Rangpur (d; f) presenting
atypical leaves and growth; nucellar plants of 'Swingle' (b) and Rangpur featuring typical
characteristics of the species (e); containing nucellar plant having greater force (left) and
hybrid plant less vigorous (right) (c). Photos: Horst Bremer Neto.
When the plants selected present height between 15 and 30 cm, the root system
sufficiently developed to maintain the clod fixed after its removal from the plastic
tube and mature stem, the transplanting of rootstocks for larger containers is
performed (Figure 4.6c), where they will remain until the end of the production
cycle. It is recommended that the substrate is irrigated to facilitate the removal of
the plastic tube plant with intact clod.
Transplanting to the final bag can be carried out with intact clod or removing a
part or all of the substrate (Figure 4.6b). The removal of the substrate allows
visualization of the roots and disposal of defective plants root system (Figure 4.6a).
Due rootstocks disposal due to malformation, occurrence of zygotic embryos,
among others, should overestimate the amount of the rootstocks to be produced
in two to three times the amount which is desired. Overall, discards are more than
30%, still higher in lime rootstocks of ‘Rangpur’, which reaches up to 60% of
disposal. The impact of rootstocks disposal on production costs is high and nursery
gardener should establish strategies to take advantage of at least 70% of tubes.
The selection and sowing of more seeds per tube are valid strategies and maximize
rootstocks ratio obtained by plastic tube used. In the selection of seeds, nursery
gardener must remove the seeds were empty, defective, broken and blackened by
attacking any pathogen. When purchased from other nurseries, the rootstocks
used in the production of seedlings should be sourced from registered nurseries in
Figure4.6 Rootstocks of Swingle presenting defective root system (tortuosity in plant
cervical region indicated by the red arrow) (left) and a normal root system (right) (a);
Rootstocks of Rangpur ready for transplanting (b); rootstocks after transplanting in bags (c).
Photos: (a) and (c) Horst Bremer Neto, (b) Simone R. Silva.
The citrus Nursery Practices in Brazil……………… 27
4.2 Production, harvest, processing and storage of budwoods
The budwoods used in the production of citrus nursery tree are obtained from
plants grown and formed solely for this purpose (budwoods source tree). Bud
grafting or Budding is a particular type of grafting with the scion consisting of a
single bud attached to a piece of bark and sometimes a thin sliver of wood
underneath. Budding is the method of choice for propagating young citrus trees
because it works well for citrus and requires less skill than other types of grafting.
The budwoods should be formed necessarily from material subject to traceability
(origin proven by invoice), from budstocks plants recorded and maintained in a
protected environment, in addition to having production plan and being subject to
plant health inspections, as submitted in items 2 and 3.2.
The Rangpur lime is the most used rootstock in the formation of budwoods tree
since it induces high force at the scions allowing large numbers of shoots flows,
and consequently higher yields at harvest of bud grafting. The bud grafting can be
conducted with a (single stem) (Figure 4.7), two (double stem) or more branches
(in stride). The conduction system will influence the spacing and producing bud
grafting during the first cut. Plants conducted in a single stem enable the spacing
between pots are lower, increasing the number of plants in bud grafting and bud
grafting amount of the first cuts. Furthermore, plants conducted in a single stem
have greater strength, increasing the number of grafting bud per stem, which is,
on average, of 12 bud grafting plant by cutting.
The adequate maturity stage for bud harvest is indicated by the degree of
shoot development and maturation.
Figure 4.7 Bud grafting with four years of age, conducted in single stem (a) and
cultivated in the arranged 3L bags on countertops (b). Photos: Nardélio Teixeira dos
which must present dark green color, edges, sufficient rigidity (should not break when
folded) and without budburst (Figure 4.8). After harvesting, in order to prevent
dehydration of the branches and to facilitate the removal of budwoods, it is carried out
the removal of the leaves in clean and shaded location. In general, only the grafting in
the central part of the branch is used. When bud grafting is not used immediately, the
branches may be stored in plastic bags in a refrigerated environment (5 - 10ºC) for up
to 2 months. After this period, the branches should be discarded. It shall only be
removed from the cooling budwoods to be grafted on the same day, since the bud
grafting exposure to the environment can lead to dehydration and reduction of viability
4.3 Formation of citrus nursery tree
Containers used for the formation of citrus nursery tree after transplanting of
rootstocks, can be made of hard plastic or plastic bags, with minimum size of 13
cm in diameter and 30 cm high. Commercially, the most widely used containers
have size of 20 cm diameter and 35 cm high, with a volume of approximately 4.5
L. The nurseries must comply with the dimensions of the container, due to their
influence on the distribution of the bags in the countertop, availability of light,
irrigation and aeration. Thus, there is preference for higher containers, which allow
better root development in depth, without the number of bags per m² is reduced.
Rigid containers have the advantage of possessing side grooves, avoiding folding
of the root system. Rigid containers, however, offer a higher risk of contamination
by pathogens and higher costs related to the acquisition and disinfestation every
new production plan.
Figure 4.8 Adequate shoot development stage for bud harvest. Photos: Horst Bremer Neto.
The citrus Nursery Practices in Brazil……………… 29
Plastic bags do not have the grooves, but are disposable, without return, washing,
disinfection, have a lower cost and enable greater agility of the planting operation.
Some producers use their own bag as a protective barrier against ants and stem
shading, reducing the need for bud bursting. According to the federal legislation (IN
48) and the State of São Paulo (CDA Ordinance No. 5), the substrate for the production
of changes cannot contain land from any source. The substrate used in this production
step may be the same as used in the formation of rootstocks, however, with larger
The budding should be performed when the stem of the rootstocks present
favorable conditions for the separation of wood bark and diameter between 0.5 and
0.8 mm (Figure 4.9). This condition is achieved from 3 to 5 months after transplanting
rootstock to the bag. Grafting height depends on the scion used, adopting minimum
height of 20 cm for 'Citrus limon (L.) Burm f.) and acid 'Tahiti' lime (Citrus latifolia
Tanaka) and 12-15 cm for the other scion cultivars. According to IN 48, the budding
should be conducted between 10 and 20 cm, measured from base plant, except when
the nursery tree is from lemons or when crops intended for the production will be
harvested mechanically. In these cases, the budding of time must be taken between
20 and 40 cm. In the days prior to budding, irrigation favors the detachment of the
bark of the rootstock. Some days before, the budding must be performed the
"cleaning", which consists of removing spikes and lateral shoots from the rootstock
top region up to 10 cm above the region budding. Grafting may be accomplished by
different methods, bud bursting and "T" normal or inverted "T" frequently used
(Figure 4.9b). After grafting, the budwoods is tied with plastic tape (Figure 4.9c),
common or biodegradable, so there is fixation and reduction of graft water loss. When
used common tape, it should be taken 12 to 16 days after grafting, when fixing or
healing is checked between the rootstock and the bud (Figure 4.9d). The maintenance
of the common narrow ribbon after setting the bud grafting may harm the
development of seedlings. Bud fixed has a typical green color, while the dead bud
grafting has brown color. The bud bursting and growth of bud grafting are favored by
breaking the apical dominance of the rootstock, which can be performed through
different techniques, among them the decapitation (5cm above the grafting point)
and the rootstock stem bending near to bud grafting (Figure 4.9c). The execution of
the bending is more time consuming, difficult management of the plants and slows
the onset of bud bursting, but it induces greater vigor to bud bursting, favoring the
development of the stem in one vegetation flow with shorter change training, and
technical most commonly used in commercial citrus nurseries.
The bud bursting should be conducted in a single stem with the help of tutors,
until complete maturation of citrus nursery tree, which occurs 3-5 months after
grafting (Figure 4.9d). The bud bursting staking should be performed when reaching
20 cm in length with fiber rod or metal (galvanized), thin and rigid to avoid damage to
the root system when inserted into the substrate. The stem of the rootstock should
be eliminated when the bud bursting the scion is with height between 20 and 30 cm,
or when the first flush has ceased growth (approximately 50 days after budding),
(Figure 4.9e). The final growth of citrus nursery tree, technical manager must collect
and send samples of leaves, roots and substrate to the laboratory accredited by the
CDA to carry out the tests of CVC, HLB, nematodes and Phytophthora.
When the citrus nursery tree is ready, the scion stem decapitation should be
held in a minimum height of 35 cm to 45 cm for tangerines and other citrus cultivars,
as from the plant's lap.
The Citrus Nursery Practices in Brazil 31
Figure 4.9 Rootstock of ‘Swingle’ citrumelo at the point of grafting (a); bud grafted in
inverted “T” shape (b); bending and plastic tape after grafting (c); bud bursting beginning
(d); staking of bud burst with plastic stem(e); in budburst stage of weaning (f). Photographs:
Horst Bremer Neto.
It is desirable that the citrus nursery tree reaches the minimum of pruning height
only when a growth flow, since the greater the number of flows, the greater the
time of formation. The location of the pruning must be brushed with paint based
on latex, to avoid possible contamination by pathogens and prevent water loss. At
this stage, the citrus nursery tree is called "stick" and is ready for
commercialization and planting. Some growers have adopted the planting with
primary branches (with three or four budburst derived from the main stem), which
requires larger containers with a volume of 6 liters and increased training time,
ranging from 6 to 8 months. According to the laws of the State of São Paulo, citrus
nursery formed with single stem (stick) and those formed with primary branches
can remain in the nursery for at most 15 and 24 months, respectively, from the
rootstock transplant. For other states, regulated exclusively by IN 48, single stem
seedlings can remain in the nursery up to 24 months in the case of intergrafting
plants or coming from the rootstock Poncirus trifoliata (Poncirus trifoliata (L.) Raf.)
and its hybrids. In other cases, single stem seedlings and primary branches can
remain in the nursery until 18 and 24 months, respectively. At this stage of the
production cycle, discards can exceed 25%. However, careful selection of
rootstock, grafting quality, nutrition, irrigation and in other cultural practices can
reduce the rate of rejection for 5-10%, values considered ideal. It is recommended
that after the shipment of citrus nursery tree, the countertops are cleaned and
disinfected before another batch of young citrus tree is introduced.
In the nursery can also be produced tree interstocks or with two rootstocks. The
nursery tree interstocks are produced in order to prevent incompatibility between
the rootstock and the scion by inserting farming compatible with both scion and
rootstock. Thus, for example, it is possible to form orange plants “Pera” (Citrus
sinensis Osbeck) or “Murcott” tangor (Citrus sinensis Osbeck x Citrus reticulata
Blanco) grafted on “Swingle” with the help of an orange intergrafting “Hamlin”
(Citrus sinensis Osbeck) or “Valencia” oranges (Citrus sinensis Osbeck) with 5 to 10
cm in length and inserted 10 cm high of rootstock (Figure 4.10). On the other hand,
the seedlings with double rootstock are those that are used more than one
rootstock, to preserve the plant in case of a pathogen affecting the main rootstock.
By this technique, an additional rootstock, another citrus species, is subgrafted
laterally scion. This technique is often used when found the occurrence of CSD in
orchards that used the Rangpur rootstock as in the North of the State of São Paulo.
According to IN 48 at the time of marketing, the citrus nursery tree with single
stem and scion formed must have a minimum diameter of 0.5 cm and 0.7 cm,
respectively, measured 5 cm above the grafting point. In the case of scion formed
seedlings, the main stem must have been pruned between 30 and 60 cm,
measured from the grafting point. Seedlings should still have mature tissue,
upright branches, without physical damage, cut of rootstock scarred and
difference in diameter between graft and rootstock less than or equal to 0.5 cm,
measured 5 cm above and below the grafting point, constituting a single stem and
upright (max. 15º) (not applicable to citrus nursery tree unterstocks). The root
system should be well distributed with radicle occupying all or almost all the
volume of the substrate being admitted maximum of 5% of defective seedlings
(coiled above the container bottom, broken or length less than 20 cm). The
methodology for sampling seedlings to root system evaluation purposes can be
found in IN 48.
Figure 4.10 Citrus nursery tree interstocks composed of ‘Swingle’ citrumelo and 'Hamlin'
orange grafting 'Pera' sweet orange. Photo: Horst Bremer Neto.
The Citrus Nursery Practices in Brazil 33
Irrigation management in citrus nursery production systems in protected
environment is essential to maximize plant growth. Through proper management,
it can influence the growth rate, the relation root: aerial part, discard rates of
seedlings and plant performance in the post-planting phase. Moreover, the base
of commercial substrates used consists of Pine bark or coconut fiber, which can
undergo drying in the absence of suitable irrigation affecting the growth and
seedlings quality, in some cases, an irreversible way.
Irrigation can be performed with aspersion systems (Figures 5.1a, c and d) or
localized (Figure 5.1b). Aspersion system can be manual or automated. In the
manual irrigation aspersion irrigation systems is performed by means "showers",
or other devices (Figures 5.1c; d).
Figure 5.1 Irrigation system for automated sprinkler used in rootstock prodution (a); located
irrigation system (b); irrigation systems by manual sprinkler (c; d). Photos: (a) Nardélio Teixeira
dos Santos, (b) Vivecitrus, (c) Horst Bremer Neto, (d) Simone R. Silva.
Aspersion irrigation systems require greater amount of manpower and water in
relation to localized irrigation systems, and promote wetting the leaves, favoring
the occurrence of pathogens infections like fungus Guignardia citricarpa, causal
agent of black spot and of Xanthomonas citri subsp. citri bacteria, causal agent of
citrus canker. The localized irrigation is performed by means of microtubes, also
called "spaghetti tube", bag by bag, directly on the substrate without aerial parts
of wetting, disfavoring the occurrence of black spot, and canker of citrus, which
makes this irrigation system the most recommended under the phytosanitary
aspect. Due to lower waste of water, applied water volume is lower compared to
irrigation by aspersion. Moreover, the need for hand labor is reduced, since the
system operation can be completely automated. On the other hand, localized
irrigation requires higher initial investment and greater care in the management
of irrigation and fertigation.
When other factors are not limiting, the maximum growth of citrus nursery tree
and rootstocks occurs when moisture from the substrate is maintained in the
container capacity (maximum water content retained in the substrate). However,
due to the need to obtain uniform distribution of water and nutrients throughout
the volume of the substrate as well as the need to remove the residual salts
resulting from the application of fertilizer, it is common practice to apply additional
amount of water, called leaching fraction. Generally, the commercially applied
leaching fraction is 25%. However, this value is variable depending on the water
quality and the tolerance of plants to the salts present in water and fertilizers.
The weighing of the containers allows the monitoring of water consumption
more often, and to establish a minimum weight, irrigation is carried when this
weight is reached. By this method, it must know the weight of the bag when the
substrate is at its maximum water retention capacity (container capacity) and the
weight of the bag before the irrigation. Based on these values, it calculates the
volume of water to be applied by means of the following equation:
VI = (Cc – Ps)/ (1- Fl)
where VI is the water volume if applied per bag (ml); Cc, is the weight of the bag in
the container capacity (g);
The Citrus Nursery Practices in Brazil 35
Ps is the weight of the bag before irrigation (g); and Fl is the leaching fraction,
decimal (SOARES, 2003). We point out that other methods of determining substrate
moisture may be used, such as tensiometers that allow indirect determination of
moisture from the substrate by means of instruments called tensiometers.
The irrigation interval (irrigation frequency) is variable depending on the seedling
growth stage, local weather conditions and the type of substrate. In general, when
the substrate is based on Pine bark, irrigates up to once a week in the winter
months, while in summer, irrigates up to three times a week. When used
comprising coconut fiber substrate, which has a higher water retention capacity,
irrigates once every 10 days in winter and once or twice a week in summer.
Fertilization is fundamental practice for the quality and speed of formation of
citrus nursery tree, since the substrates used are inert and do not contain the
nutrients necessary for the proper development of the plants. In general, the most
required nutrients in the formation of citrus plants nursery in descending order are:
nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S) and
phosphorus (P). Although these elements are found in lower concentrations, boron
(B), iron (Fe), copper (Cu), manganese (Mn), zinc (Zn) and molybdenum (Mo) have
important roles in plant growth and must be included in the nutrition program of
citrus nursery trees.
In Table 1 are presented the optimal foliar concentrations of N, P, K, Ca, Mg and S
for the growth of the main rootstocks and combinations scion/rootstock used
commercially during the winter and summer seasons. These values were obtained in
a study published in Technical bulletin of Nutritional Standard of Citrus nursery tree
and can be used as reference for assessing the nutritional status of rootstocks and
citrus nursery plants at different stages of development.
Table 1. Optimum leaf concentration1 of macronutrients estimated to rootstocks and citrus
nursery tree in the end of the first bud flush and before final pruning, in two growing
1 Sample obtained by collecting three leaves, located in the middle third of the rootstock or citrus
nursery tree, in 20 plants for production countertop. Source: Bataglia et al. (2008).
Season Rootstock/Nursery tree g Kg -1
(1st bud flush)
(1st bud flush)
The Citrus Nursery Practices in Brazil 37
Considering that irrigation is performed with high frequency and volume of
containers is limited, the leaching of fertilizer applied becomes high, which reduces
its availability to the plants. Thus, the gradual supply of nutrients is a
recommended strategy. The use of slow release fertilizers or split application of
soluble fertilizers in small doses, along with water irrigation technique called
fertigation, are the most efficient means for the gradual application of fertilizers.
Due to the lower cost, fertigation is the most used technique in commercial citrus
In fertigation, the amount of water applied and the frequency of application will
vary depending on the age of the nursery tree, the environmental conditions and
the type of substrate used. Table 2 sources are presented in N, P, K, Ca, Mg, S and
Cu commonly used and dilution suggestion for production of rootstocks and citrus
nursery tree on substrate composed of Pine bark. The micronutrients Fe, B, Mn,
Zn and Mo should be added to the solution so that there is nutritional deficiency
that impairs the growth of nursery tree. These nutrients may be added in solution
by means of commercial formulations available on the market, in dilutions
recommended by the manufacturer.
The monitoring of electrical conductivity (EC, a measure of the concentration of
salts) and pH (measure of acidity of the solution) are fundamental to the rational
management of the application of nutrients. For the evaluation of EC and pH, it
must be used two substrate parts to one-part water. It is recommended that the
EC is maintained between 0.8 to 1.2 dS m-1 in summer and between 1.2 - 1.5 dS m-
1 in winter and pH between 5 and 6 in both seasons.
Table 2. Fertilizers used in fertigation and dilution suggestion for nutrient solutions used in
formation of rootstocks and citrus nursery tree.
Dilution (g 1000–l L)
N and Ca
N and P
N and K
S and Mg
S and Cu
Source: Leandro Fukuda, 2012 (personal information).
In the production of rootstocks, the frequency of irrigation and drainage are higher,
keeping the EC in low amounts, around 0.4 to 0.5 dS m-1, without harming plant
growth, as fertigation is conducted almost every day.
The Citrus Nursery Practices in Brazil 39
7. Nursery Pests and Diseases
In Brazil, the transport of seeds, budwoods, citrus nursery trees and rootstocks
infected by pathogens has been the primary means of spread of major diseases of
culture between states, municipalities and citrus properties. The production of
pathogen free citrus nursery trees is the most important measure in preventing
the entry and establishment of diseases in citrus orchard. All major diseases of
citrus of culture can be spread by citrus nursery tree. Therefore, knowledge
involving forms of infection of propagating material occurs and the preventive
measures are very important for the spread of pathogens via changes will not
occur, especially for areas free of disease.
In the case of pests, spread by citrus nursery trees are less common due to the
easy viewing of insects and mites in frequent inspections, combined with
preventive and effective control with insecticides even in nurseries. For diseases,
however, the spread of pathogens by citrus nursery trees can occur without
apparent symptoms. The pathogens may infect tissues of different ways: a)
pathogens transmitted by grafting with contaminated budsticks and systemically
colonizing the plant by phloem and xylem, as viroids of exocortis, the cachexia or
xiloporose, the virus sorosis, tristeza virus and CSD and the bacteria that cause CVC
(Xylella fastidiosa) and HLB (Candidatus liberibacter spp.); b) pathogens that may
be present on the substrate used, whose disease can be expressed after the period
of production and citrus nursery tree trade, such as Pratylenchus semipenetrans
nematodes and Tylenchulus jaehni and fungi that causes gummosis caused by
Phytophthora spp.; c) pathogens transmitted by insect vector, the disease of which
can be expressed after the period of production and citrus nursery tree trade, such
as CSD and bacteria causative agents of CVC and HLB; d) pathogens dispersed by
wind and humans, but it is necessary water-free in tissue surface to occur to
infection, such as citrus canker bacterium (Xanthomonas citri subsp. citri), that can
express symptoms still in the nursery, and the fungus Guignardia citricarpa that
causes black spot, a disease that does not manifest itself in leaves and branches in
Therefore, the whole process of production of the citrus nursery trees should be
monitored by citrus nursery growers and preventive actions should be taken to
ensure that the citrus nursery trees are produced and marketed free from harmful
pathogen to citriculture.
7.1 Important citrus diseases spread by citrus nursery plants
7.1.1 Tristeza disease and Citrus Sudden Death (CSD)
The virus that causes the citrus tristeza disease is transmitted by graft
propagation using infected budwood, the main propagation method used in the
production of citrus nursery tree. As the transmission of the virus occurs by aphids
(aphids), it is important to protect source of budwoods as well as citrus nurseries
with protective insect proof structure. The main aphids citrus tristeza virus (CTV)
transmitters are: the black aphid of Toxoptera citricida citrus, in addition to Aphis
gossypii and Aphis spiraecola.
The symptoms of tristeza disease in the field are variable depending on the virus
strain present and scion/rootstock combination affected. Severe strains, as
opposed to mild strains, of the virus cause severe stem pitting, seedling yellows,
or quick decline on sour orange rootstock which result in reduced crops or loss of
In Brazil, the virus and the vector are endemic, thus, the alternative for control
of tristeza disease is the use of cultivars tolerant rootstock, such as ‘Caipira’ sweet
orange (Citrus sinensis L. Osbeck), the ‘Rangpur’ lime, the ‘Rough’ lemon (Citrus
jambhiri Lush.), ‘Sunki’ mandarin (Citrus sunki Hort. ex. Tan.) and ‘Cleopatra’
mandarin (Citrus reshni Hort. ex. Tan.) and ‘Swingle’ citrumelo. The cultivar scion
should preferably be pre-immunized with mild virus strains.
CSD, as well as tristeza disease, is a highly destructive disease, of easy spread, t
transmitted by air vector and budsticks, which affects all cultivars of sweet oranges
(Citrus sinensis), tangerine (Citrus reticulate Blanco) and “Ponkan” (Citrus
reticulate Blanco), ‘Tahiti’ lime and Persian lime (Citrus limettioides), when grafted
on ‘Rangpur’ and Volk (Citrus volkameriana Tan. & Pasq.). Due to intolerance of
these rootstocks to the presence of the virus CSD, the scion sap flow to the root
becomes blocked, which reduces the development of root system and the water
absorption capacity and minerals, leading to death of the plants. The leaves of
plants with CSD lose their luster and fall. Budburst, when they occur, are less
vigorous and with thin narrow leaves. The yellowing which occurs inside the bark
of the rootstock below the graft area is a characteristic symptom of the disease,
visible by removing the peel or scrape the inner layers.
The Citrus Nursery Practices In Brazil 41
These symptoms are easily observed in plants from two years of age, especially in
early spring, with the occurrence of rainfall. The CSD is rarely diagnosed during
citrus nursery tree production phase.
The CSD is present mainly in the south of Minas Gerais Triangle and in the cities
of northern and northwestern regions of the state of São Paulo, where there are
high temperatures and water deficit. However, the similarities between CSD and
tristeza disease, it is believed that the vector is the same, the black aphid. As the
causal agent of CSD can also be transmitted by graft propagation using infected
budwood, there is an imminent risk of its spread to other producing regions if
preventive measures are not taken. In an attempt to minimize the spread of the
CSD was prepared Rule 16, which prohibits, for all Brazilian states, trade and transit
of plants and propagation material (seeds, budwoods and rootstocks) of citrus
produced in nurseries without protective insect proof structure in areas with
occurrence of CSD for free municipalities of the disease.
7.1.2 Citrus canker
The citrus canker is a quarantine disease in many countries, caused by the
bacterium Xanthomonas citri subsp citri. The pathogen is spread over long
distances by rains associated with winds and infected citrus nursery tree.
Historically, the spread of canker citrus is closely related to the transit of
propagative plant material contaminated.
The citrus canker causes lesions on leaves, stems and fruits and consequently
leaf and fruit fall, affecting the production of infected citrus nursery trees.
Symptoms start in the leaves by the appearance of yellow stains, small that
gradually increase and become brown staining lesions, protruding on both sides of
the leaf. In branches, the lesions are prominent, with straw and brown coloring. In
fruits, the lesions are similar to those found in the leaves. With the advancement
of the disease, however, the lesions enlarge and protrude, with a yellow halo
around it and with brown center. The citrus canker bacterium is not systemic in
the citrus plant tissue, being restricted to where the infection occurred. The
bacterium penetrates into new tissues by stomata and natural openings or wounds
made by thorns and insects.
The infection occurs through natural openings only in young tissues. The leaves and
stems are susceptible up to 6 weeks after the beginning of its development. The fruits
are susceptible to approximately 90 days after petal fall. When infection occurs after
this period, the lesions are very small. The increased incidence of citrus canker in
orchards is associated with the presence of leafminer (Phyllocnistis citrella). Lesions
caused by leafminer facilitate the bacteria enter the plant allowing the installation of
Thus, the production of citrus nurseries trees covered with waterproof material,
as well as the use of localized irrigation, which prevents the leaf wetness, are
extremely important to minimize infections by bacteria and possible spread of the
disease in citrus areas.
7.1.3 Citrus variegated chlorosis and Huanglongbing
The citrus variegated chlorosis (CVC), caused by the bacterium Xylella fastidiosa,
was found in orchards in the Northwest region of the State of São Paulo in the
1980s. The unknown of its nature and its modes of transmission either by graft
propagation using infected budwood such as several species sharpshooter
leafhoppers vectors confirmed only years later, made its incidence increased
rapidly in all regions of São Paulo, causing heavy losses in production.
The increase of the disease was due mainly to the use of mined accounting citrus
nursery trees. In the 80 and 90, almost all the propagation material was produced
in the open and as the causal agent bacterium is transmitted by several species of
leafhoppers contamination of citrus nursery tree was inevitable. In open field
nurseries, systematic spraying with insecticides do not prevent contamination of
citrus nursey tree, because the population of insect vectors is never fully
exterminated. CVC is transmitted through seed and grafting. It can also be spread
via the movement of infected citrus nursery stock and plant material (budwood,
cuttings, rootstock). CVC can also be spread by xylem-feeding vectors, such as the
The bacterium that causes CVC is transmitted by 12 different species of
sharpshooter. The best known are Bucephalogonia xanthophis and Macugonalia
leucomelas, efficient transmission of the pathogen. Contamination occurs when
sharpshooter feed on xylem sap of plants contaminated acquiring the bacteria and
transmitted to healthy plants. After diagnosing the disease in the field, it is
necessary to eliminate the branches of infected plants when they are in early stage
or total elimination of diseased plants in the intermediate stage terminal.
The Citrus Nursery Practices in Brazil 43
The bacteria develop in the xylem clogging vessels and hampering transport of
raw sap from the roots to the aerial parts of the plant. Symptoms of the disease are
more evident during the dry season. Foliar symptoms first appear at the top and
middle of the scion and then spread to the rest of the plant. Mature leaves are
variegated leaf chlorosis, which begins by small yellow spots on its upper face,
evolving to chlorosis similar to zinc deficiency. The corresponding lower face appear
small scores brown color. These scores evolve into intense brown colored lesions,
which can be grouped and become necrotic. Young leaves may have small size and
tapered and canoe shaped. In older trees, the symptoms are localized, affecting
few stems. Fruits of affected branches have their development compromised,
remaining reduced size, hard and useless for trade and processing. Trees with
severe CVC attacks may have their growth stalled and present death pointers.
However, these trees rarely die but remain unproductive.
CVC occurs in all sweet orange cultivars, ‘Pera’, ‘Natal’ ‘Hamlin’, ‘Bahia’,
‘Baianinha’, ‘Valencia’, ‘Folha Murcha’, ‘Barão, regardless of the rootstock used.
They have not been displayed symptoms in ‘Ponkan’ tangerines,"Mexerica Rio"
mandarin, ‘Murcott’ tangor, lemons and ‘Galego’ acid lime, which although
asymptomatic, may have the bacteria in their tissues, and therefore sources the
bacterial inoculum. As control measures in nurseries, both the stock plants as the
citrus nursery tree should be in protective insect proof structure or greenhouses
protected with anti-aphid screens.
The huanglongbing (HLB, ex-greening), associated with bacteria Candidatus
Liberibacter spp., is considered the most devastating disease of citrus in the world.
HLB was first found in Brazil in 2004, in the region of Araraquara, São Paulo. In
addition to citrus plants, the bacterium also colonizes the myrtle (Murraya
paniculata), ornamental plant commonly used as a living fence. The handling of such
infected and asymptomatic plants can often serve to increase the speed of
dissemination of the disease. The bacterium associated with HLB is transmitted by
insect vectors, the psyllids (Diaphorina citri). For the prevention of contamination of
powdered citrus nursery tree Candidatus Liberibacter spp. transmitted by Diaphorina
citri, nurseries throughout the production process must be protected by anti-aphid
7.1.4 Citrus black spot
Black spot is a quarantine disease caused by the fungus Guignardia citricarpa,
which produces lesions on citrus fruits. The disease prevents the export of in
natura fruits and causes major losses in citrus production for the industry, for
cause premature fruit drop before complete maturation. In Brazil, the black spot
was reported in 1980 affecting commercial orchards in the state of Rio de Janeiro
and its spread over long distances is related to asymptomatic infected citrus
nursery tree. As in sweet orange leaf the black spot symptoms are not
manifested, it becomes impossible the visual diagnosis. The pathogen to infect
the citrus nursery tree needs water free of leaves and stems. The production
nurseries protected anti-aphid screen does not protect the pathogen enters the
nursery, because the fungal spores are much smaller and can pass through the
screen. However, the coverage of the nursery with waterproof material and
localized irrigation ensure that no wetting occurs in the tissue and infection of
the citrus young plants by the fungus.
7.1.5 Citrus Gummosis and Nematodes citrus
The gummosis is a disease caused by Phytophthora nicotianae and P.
Citrophthora, and is considered one of the most important diseases of citrus in
Brazil. The main mechanism of this pathogen spread is through citrus nursery tree,
soil, irrigation water or contaminated substrates. The pathogen can survive for up
to a year in soil and substrates and can be introduced in nurseries for these
materials. Another means of introduction of the pathogen in nurseries is the
irrigation water. The pathogen has biflagellate zoospores that allows locomotion
by water until the root system of the young trees in nurseries. Therefore,
preventing the entry of Phytophthora spp. in nurseries, it should be clean the
substrates and treating irrigation water. Container grown should be distant from
the ground to prevent contamination.
When the seeds have begun to germinate, the pathogen can infect tissues of
the base of hypocotyl with depressed lesions of dark color which increase in size
and eventually causing the death of seedlings. This disease in nurseries is known as
damping off. The pathogen can also infect and cause stem seeds before
germination, compromising stand. The citrus nursery tree produced without
apparent symptoms, however, the pathogen can remain on the roots of infected
plants, as well as on the substrate that accompany. In order to reduce the incidence
of Phytophthora spp. In nurseries recommended treatment with fungicides or
The Citrus Nursery Practices in Brazil 45
thermotherapy treatment of the irrigation water (copper sulfate 20 ppm) nitrogen
fertilization and to avoid intense.
The nematodes Pratylenchus, semipenetrans and Tylenchulus jaehni citrus
possess a restricted ability of movement. The main mechanism for dissemination
over long distances is the transportation of infected citrus nursery tree. The citrus
nursery tree shows no apparent symptoms, however, the pathogen can remain on
the roots of infected plants, as well as being present in the soil or substrate
accompanying the plant nursery. The spread of citrus nursery tree was identified
as primarily responsible for the wide spread of these pathogens throughout the
State of São Paulo, while still producing citrus nursery tree in the open field,
planted directly in the ground.
7.2 Main pests in nurseries
Aphids are sucking insects that can cause direct and important indirect damage.
The most common species in citrus are the black aphid (Toxoptera citricida), green
peach aphid (Aphis spiraecola) (Figure 7.1) and the green peach aphid-of-cotton
(Aphis gossypii). Aphids are insects easily recognizable due to the size and
formation of colonies (Parra et al., 2005).
Figure 7.1 Branches infested with black aphid (a) and green peach aphid (b); wrinkled leaves
and branch atrophied by aphid attack (c); black aphid (d) and green peach aphid (e). Photos:
Heraldo Negri de Oliveira.
The most important direct damages are caused by sucking sap and injection toxic
substances by saliva leading to formation of wrinkled leaves and stunted shoots
when aphid infestation is high. Indirect damage is related to the transmission of
the tristeza virus and formation of sooty moldin on the affected organs (darkened
cover formed by fungi of the genus Capnodium sp., which feed on the rich
substance sucrose excreted by aphids). The presence of sooty mold affects
respiration and photosynthesis of the affected plant, reducing its growth.
Citrus leaf miner (Phyllocnistis citrella)
The citrus leaf miner is a small moth (4.0 mm wingspan) whose larvae feed on
the new leaves, cause injuries in the form of serpentine known as mines or
galleries, usually on the underside of leaves (Figure 7.2). These lesions damage the
leaf tissue, reducing the photosynthetic area may lead to dryness and premature
leaf fall and reduction of the affected budding growth (Parra-Pedrazzoli & Bento,
2008). Additionally, lesions favor the entry of opportunistic microorganisms, as
well as the causal agent of bacteria citrus canker (Figure 7.2).
Figure 7.2 Citrus leaf miner: life cycle (a) and leaves damage (b). Photos: Heraldo Negri de
The Citrus Nursery Practices in Brazil 47
White Mite (Polyphagotarsonemus latus)
The white mite can stay in plants belonging to more than 60 families, found in
several species of the Citrus genus. The mite has white to pale yellow, according
to the development stage. Females are larger than males and measure, as adults,
0.17 mm in length by 0.12 mm width (Oliveira & Pattaro, 2008) (Figure 7.3).
In addition to causing damage to fruit, the toxic action of its saliva causes
deformations sheets, requiring its control in nurseries. Budburst attacked originate
asymmetrical leaves, lanceolate, with the edges facing down, leading to the
formation of necrotic areas (dark) on the underside of leaves (Oliveira & Pattaro,
Mexican Mite (Tetranychus mexicanus)
Mexican mite can be found in other plant species, though citrus plants are its
primary host. Its color depends on the feed. To feed on leaves and unripe fruit gets
green color with dark spots on the back.
Figure 7.3 White mite: eggs and adults (male and female). Photos: Heraldo Negri de Oliveira.
Females and males reach 0.5 and 0.4 mm in length as adults, respectively. The
oviposition occurs in spiderweb, produced in abundance in citrus plants grown in
greenhouses (Figure 7.4).
The mexican mite infestation the leaves, cause discoloration, formation of
yellow areas and intense defoliation.
Purplish Mite (Panonychus citri)
The female has oval body shape, length of 0.5mm and intense red color, being
easily observed on the green parts of the plant (Figure 7.5). The male is smaller
and tapered body (Oliveira & Pattaro, 2008). The purplish mite affects leaves,
branches and fruits. When attacked, the leaves have yellowed numerous scores
(mottling) and, in severe infestations, reduce plant vigor and can cause defoliation
and drought pointers (Figure 7.5).
Texas Mite (Eutetranychus banksi)
The Texan mite has bronze-yellow-bright variable color with greenish spots to
dark brown in the lateral region of the back. The female has rounded, flattened
shape with 0.5 mm length. Males are smaller and triangular shape. It does not form
webs, and the position is held along the ribs or on the rim of the sheets (Figure
The Texas mite infests predominantly the upper surface of the leaves. The attacked
leaves are discolored scores, loss of gloss, becoming chlorotic and may occur
Figure 7.4 Texas mite: Eggs, nymphs and adults and damage to leaves and branches.
Photos: Heraldo Negri de Oliveira.
The Citrus Nursery Practices in Brazil 49
Figure 7.5 Purplish mite: egg, larva and adult and leaves in damage. Photographs: Heraldo
Negri de Oliveira.
Figure 7.6 Texas mite: Eggs, nymphs, larvae and adults (male and female) and damage on
leaves. Photos: Heraldo Negri de Oliveira.
Cochineal insects, like aphids, are sucking insects that cause direct damage by
sucking sap and injection of phytotoxins, indirect, by favoring sooty mold
formation. Citrus can be attacked by different species of cochineal. In citrus
nurseries, the most common are green cochineal (Coccus viridis) (Figure 7.7),
australian cochineal (Icerya purchasi) (Figure 7.8), white cochineal (Planococcus
citri) (Figure 7.9) and rufous cochineal (Selenaspidus articulatus).
Figure 7.7 Green Cochineal: nymphs, adults, branches and petioles infested. Photographs:
Heraldo Negri de Oliveira.
Figure 7.8 Australian cochineal: life cycle and branch showing high infestation.
Photos: Heraldo Negri de Oliveira.
7.3 Control of pests and diseases in nurseries
As shown in previous sections of this manual, control of insect vectors and
important diseases spread by citrus seedlings is carried out preventively through
adequate infrastructure and other care throughout the entire production process.
However, other pests and diseases may occur in the nursery, bringing losses for
the production of rootstocks, budwoods and citrus nursery tree, requiring other
preventive or control actions, with emphasis on the application of pesticides.
The application of pesticides can be performed with different equipment,
depending on the nursery's production capacity, availability of skilled labor, product
type and desired operating income. In large nurseries, sprayers driven by electric
motor are the most used (Figure 7.10). Spraying should start by Kiln background,
walking toward the front door (Figures 7.11 e 7.12).
The Citrus Nursery Practices in Brazil 51
The coverage of plants is a key aspect to the success of the control operation.
On countertops with plants present height greater than 40cm, the deposition of
products is impaired. In this condition, the application must be performed from
both sides of the countertop (middle countertop application), requiring the transit
applicator in all lanes (Figure 7.11). On countertops with plants present height of
less than 40 cm, deposition is favored, allowing the application to be carried out
from one side of the countertop (full countertop application) (Figure 7.12).
Figure 7.9 Cochineal white: eggs, nymphs and adults (male and female) and branch
showing high infestation. Photos: Heraldo Negri de Oliveira.
Figure 7.10 Electric sprayer with tank with a volume of 180 liters (a) and spray gun used in (b). Photos:
In this condition, the applicator will transition on alternate lanes, increasing the
efficiency of the application. Another aspect that must be considered is the
location of the target, whether internal (old leaves), external (new leaves) or the
neck of the plant. In the latter, they are applied systemic products plant to plant
using spray costal.
Under certain conditions are needed weekly applications for leaf miner control of
citrus and mites. Every other week they can be applied fungicides and bactericides
Figure 7.11 Forwarding to spray pesticides in citrus nursery tree taller than 40 cm grown in
protected environment. Source: Ricardo Krauss, 2014 (personal information).
Figure 7.12 Forwarding to spray pesticides in citrus nursery tree with height less than 40 cm
grown in protected environment. Source: Ricardo Krauss, 2014 (personal information).
The Citrus Nursery Practices in Brazil 53
For other pests are detected, such as cochineal and caterpillars, the nursery growers
should use products with higher spectrum of action or to apply specific products as
well as increasing the frequency of application. It is emphasized that preventive
applications depend on the history and risk of particular pests and disease in the
nursery. It is recommended to alternating active principles/mechanisms of action to
prevent the emergence of resistant populations of pests.
In the event of disruption of coverage (torn plastic), should be carried out spraying
insecticides preventatively on the day of realization of the damage on the cover. If the
nursery remains open for longer than one day, it is recommended to perform the
insecticide application at least every two days. After closing the cover, should proceed
another insecticide application in preventive.
The occurrence of weeds in bags and vases is common even with the use of the
substrate. If not controlled, the weeds can cause direct damage such as reduced
growth, and indirect, serving as host of pests and diseases and physical barrier to
crop protection applications and pinching and grafting operations.
The control must be performed manually in bags and vases since rootstocks,
budwoods and citrus nursery trees are very vulnerable to drift, and find
themselves under development, whose damage phytotoxicity of herbicides can be
severe and irreversible. When new shoots are subject to breakage, manual control
should be delayed until the shoots are ripe.
In the space between the citrus plants and under the countertops, can be used
contact herbicides applied post-emergence herbicides or applied pre-emergence
at the end of fallowing.
The Citrus Nursery Practices in Brazil 55
9. Scions and rootstocks
The number of scions and rootstock cultivars used commercially in Brazil is
reduced, although there are numerous alternatives for both groups. A greater
diversification of cultivars is observed among those used as scions. Sweet oranges,
tangerines, lemons and acid limes are the most cultivated, especially sweet
oranges, which are present in larger area. Historically, the number of rootstocks is
further restricted, predominantly only one rootstock mostly cultivated area.
The low diversification of scions/rootstocks combinations can have serious
consequences for the health of orchards and the economy of the producing
regions, in the case of the occurrence and aggravation of new pests and diseases.
Examples of this are the occurrence of CTV and CSD in orchards grafted in Sour
orange (Citrus aurantium L.) and Rangpur lime, in the 1940s and 2000, respectively,
when millions of plants had to be eradicated. Thus, besides the production and use
of citrus nursery tree that have appropriate genetic quality and health,
diversification of scions and rootstocks is essential practice for the sector's
Knowing the characteristics of each cultivar, the citrus nurseries can assist
growers in choosing genetic material suitable for the market in fresh or industrial
processing, and to promote the installation of orchards with high genetic diversity.
The main rootstocks used in Brazilian citrus are ‘Rangpur’ lime, ‘Swingle’
citrumelo, ‘Cleopatra’ and 'Sunki' mandarins, 'Volk' lemon and Poncirus trifoliata
(Table3). The ‘Rangpur’ lime, this is most widely used citrus rootstock in Brazil, is
used in 70% of the area cultivated by inducing the canopy it budded early start of
production, high fruit yield, drought tolerance and CTV, fast training in nursery and
compatibility with all cultivars crown used commercially in Brazil. From the
evidence of their intolerance to CSD, however, other rootstocks began to be used,
notably, ‘Swingle’ citrumelo and ‘Cleopatra’ and ‘Sunki’ mandarins. Although these
rootstock present disadvantages compared to ‘Rangpur’ lime, especially in relation
to drought tolerance, incompatibility with important scion cultivars, early yield and
vigor of the plant (higher in tangerines), benefits involving increased quality fruits,
health and longevity of the orchard are evident,
which made them the most widely used in the formation of new orchards,
especially ‘Swingle’, which currently represents 90% of orders in nurseries
associated with Vivecitrus. Other citrus species have been studied for use as
rootstocks, especially the citranges' Carrizo 'and' Troyer '(Citrus sinensis x Poncirus
trifoliata), citradias (Citrus aurantium x Poncirus trifoliata) and trifoliate, with focus
on Flying Dragon trifoliate (Poncirus trifoliata var. monstrosa), which induces a
reduction in the size of the plant, allowing greater number of plants per area and
greater ease of harvest.
The appropriate planning of the production of seeds rootstocks after to produce
citrus nursery tree, the nursery grower must know the horticultural characteristics of
each rootstock, such as number of seeds produced per fruit, seed weight and the
polyembryony (Table 3). These characteristics are variable, not only due to the
rootstock species, but also because of environmental conditions, pollinators, the
origin of the pollen and the type of fertilization (selfing or outcrossing).
Table 3. Fruits and seeds of the features recommended rootstocks for citrus cultivation in
Rootstock Fruit ripening
15 -1 68
Source: Adaptado: Oliveira et al., 2008; 1 Unavailable data.
The Citrus Nursery Practices in Brazil 57
Furthermore, producers, technicians and citrus nurseries should be aware of the
influence of rootstock on the performance of scions involving production, fruit
quality, tolerance to pests and diseases and adverse weather conditions as well as
the compatibility of scion cultivars and selected rootstocks, as in some cases, the
combination may be incompatible. In Table 4, are presented the main
characteristics of the cultivated rootstocks and those with the greatest potential
for commercial use.
There are several of options scion’s cultivars within the Citrus gender, among
them are sweet oranges, tangerines, lemons, acid limes and grapefruits.
According to report of the Department of Agriculture and Livestock Protection
of São Paulo, the most citrus varieties planted in the state in 2011 were sweet
oranges 'Valencia' 29.22% 'Pera Rio' 27.27% 'Hamlin' 12.11 % 'Natal' 11.99% 'Folha
Murcha' 3.26% and 'Valência Americana' 1.95%, 'Tahiti' acid lime 2.94%, ‘Murcott’
1.29% and ‘Ponkan’ tangerine 1.06%, and the other cultivars have made up 8.91%.
From the reported data, the characteristics of each cultivar scion in fruit
maturation function (early, mid-season and late) and the destination of
production, in natura and/or industrial processing will be highlighted.
The sweet orange 'Hamlin' is the main cultivar early maturation of the State of
São Paulo. It produces fruits of oval-shaped, almost spherical, with three to four
seeds per fruit. The bark is thin and has deep orange and well defined. The juice
has low commercial value, being light in color and flavor less than the cultivars
'Pera', 'Valencia' and 'Natal', usually aimed at specific customers or production
mixes with juices from other cultivars. The fruit juice volume has low, below 50%.
Displays total soluble solids content around 11°Brix and harvest between April and
August. Despite the low quality, this cultivar allows greater industrial processing.
'Westin' orange is a cultivar highly productive and with few seeds. Its fruits are
appreciated both for the fresh fruit market and for industrialization and, after
completing their maturation, remain for a short period in the plant.
Table 4. Horticultural performance, adaptability to environmental conditions and compatibility of the main commercially rootstocks used.
Quality of Fruits
Maturation of production
Incompatibility None Pera Pera
None None None None
1:non-existent data; Regarding diseases: S=Susceptible; T = tolerant, R = Regular; Performance and Gummosis: M = Medium; B = Low; A = High. Depth Soil: M =
Average; R = Shallow; P = Deep. Adjusted: Schâferetal.,2001; Pompeu Junior,2005; Fundecitrus,2006; Oliveira et.al.,2008.
58Bremer Neto, H.;Silva S.R.; Mourão Filho, F.A.A.; Sposito M.B. &Caputo, M.M.
The Citrus Nursery Practices in Brazil 59
The fruit, however, has intense orange color, 2 to 3 seeds, length of 61 mm,
diameter of 64 mm, average of 128 g weight, bark thickness of 4 mm, content of
vitamin C, approximately 18 mg 100 mL-1, infrequent navel, 45% juice percentage,
total soluble solids of 11.7°Brix and acidity around 1.3%.
The ‘Ruby’ orange is made up of medium-sized trees, with an average yield of
250 kg of fruits with mass around 172 g, 49% juice, intense orange color, total
soluble solids (TSS) of 9.9°Brix, 0.86% acidity and ratio 11.5, premature maturation,
fruit a very recommended both for the fresh fruit market and for industrial
The 'Valencia' orange produces large fruit, high percentage of juice, spherical to
elliptical, with convex base and concave apex, slightly rough surface smooth, with
orange pulp, 7-10 seeds, and the average height of the plant is high. It produces
fruit with early maturing to mid-season, which are co-lected in a period that
overlaps the oranges 'Hamlin' and 'Pera'. The orange 'Pera' is one of the most
planted cultivars in the State of São Paulo dental the average maturity of oranges.
Present fruits shapes varying from spherical to oblong, average weight 150g, its
bark is smooth and thin with orange color, average of four seeds per fruit. The
fruits of this variety are the most suitable for industrialization, because they have
higher yield and quality of juice, and stay in the trees for a period long time. It has,
however, an irregular flowering, an average of three per year. The plants are
vigorous, large, erect, productive, little tolerant sadness and moderately resistant
to canker citrus. They are incompatible with rootstock of ‘Volk’, Poncirus trifoliata
The most produced late cultivars are currently 'Natal', 'Valencia' and 'Folha
Murcha'. A 'Natal' orange fruit in circle shape, with 3 to 4 seeds, average weight
140 g, thin skin, light orange color and orange pulp, SST 12°Brix, acidity 1% to ratio
12. Plants are productive, reaching on average 250 kg per plant.
The orange 'Valencia' is the most widely planted cultivar in the world. In Brazil,
it is cultivated in almost all states, producing high quality fruit, with income in
excess juice 50%, appropriate relationship between total soluble solids and acidity
(ratio), fruit average weight 150-170 g, format approximately spherical and seeds
6 per fruits. The skin is thin and slightly rough surface.
The plants are vigorous, large, upright growth and productive. The fruits may
be intended both for consumption in natura and for industrial processing.
Another cultivar that have been used by growers is the orange 'Folha Murcha'
later than oranges 'Natal' and 'Valencia'. The fruits are shape rounded, weighing
between 150 to 170 g, has a high juice yield, with average SST of 13ºBrix, acidity
1%. The bark is thin and its orange color, produces 2 to 6 seeds per fruit. Although
its fruits are similar to the orange 'Valencia', plants are less vigorous, productive
and have rolled leaves. Meets quality requirements for industrial processing and
The navel orange more widespread in Brazil and in the world is the orange
'Bahia'. It has seedless fruits, average weight of 220 g, spherical, color of pulp and
intense orange peel, early maturing median, juice yield around 38%, SST 13.2°Brix,
acidity less than 1% and ratio 14. The bark is thick, slightly rough and has great
navel. The plants are vigorous, rounded crown with abundant foliage, dark green
leaves, big and open growth habit. It produces an average of 150 to 250 kg per
plant. Destined preferably in natura consumption.
The 'Lima' orange is one of the most cultivated low acidity cultivars in Brazil, with
great acceptance in the fresh market. Produces fruit with an average weight of 130 g,
with 5 to 6 seeds, early maturing, skin color and orange pulp. The fruits have an
average of 45% juice yield, content SST 10°Brix, acidity around 0.12%. The trees have
medium-sized too large, upright, productive crown, reaching up to 300 kg of fruit per
plant. The others scions’ cultivars planted in São Paulo are 'Cravo' and ‘Ponkan’.
tangerine trees present medium size, lance-shaped leaves, produce, on average, 200
to 250 kg of fruit per plant. Its fruits are flattened on the bases, with 20 to 22 seeds
per fruit, average weight of 135g and color peel and intense orange pulp. It has 48%
of juice yield, SST 10.8°Brix, acidity 0.8% and ratio of 13.5. The fruit can be intended
both for industry and for the fresh market.
‘Ponkan’ tangerine fruit has a flattened shape, with 5 to 8 seeds, average weight of
138 g, average shell thickness and protruding oil vesicles.
The Citrus Nursery Practices in Brazil 61
Skin color and intense orange pulp. It produces 43% of juice, average SST 10.8°Brix,
acidity of 0.85% and ratio of 12.7. It presents early maturing median. The fruits are
destined for the fresh market. Another cultivar of the group of tangerines is the
Tangerine Cravo (Citrus deliciosa Tenore) that produces fruit flattened with about
30 seeds, weight of 130 g, thin skin, staining pulp and orange peel. It has 40% of
juice yield, SST 10.4°Brix, acidity 0.99% and 10.5 ratio. Its plants are medium sized
with small and elongated leaves and can produce up to 200 kg of fruit per plant
which are intended for fresh consumption and also to industry.
The 'Murcott' tangor (Citrus sinensis Osbeck x Citrus reticulata Blanco) also
composes the group of tangerines. They present a medium-sized tree, with
lanceolate leaves and spiky. The plants produce on average 200 kg of fruits per
plant. The fruits have a flattened shape on average 20 seeds per fruit, weighing
140 g, with smooth and thin adhesive peel and intense orange color. The pulp has
a firm texture and orange. They have juice yield of 48%, SST 12.6°Brix, acidity
0.92%, ratio 13.7 and late maturing. Its fruits are allocated preferentially to the
market for fresh fruit, but have acceptance in industry.
In the group of acid limes, the most cultivated species are the ‘Galego’ acid lime
(Citrus aurantifolia) and the ‘Tahiti’ acid lime, both designed predominantly for
fresh consumption. The fruits of 'Gallego' acid lime is spherically shaped, with 5 to
6 seeds, average weight 35g, very thin skin of yellow color and light green squash,
yield 50% juice, 9.7°Brix acid 6.5% and 1.5 ratio. The trees are of medium size,
producing 150-200 kg. The Tahiti acid lime has large-sized trees, large leaves, large,
dark green, produces more than 200 kg per plant. Its fruits are oval shaped, have
no seeds, fruits with an average weight of 70 g, length 55-70 mm, average diameter
of 55 mm and thin shell with coloring green skin and pale green pulp. It has 50% of
juice yield, SST 9 Brix, acidity 6% and 1.5 ratio. The fruits can be used for the fresh
fruit market and industry. Due to the large size of the plant, the use of dwarfing
rootstocks, such as trifoliate 'Flying Dragon', have been used in the production of
citrus nursery trees.
10. Production Costs
The cost of production of citrus nursery tree is variable depending on many
factors such as location of the nursery, the level of technology applied in
production, amortization and maintenance of facilities and equipment, quantity
and qualification of manpower and scale of production.
The main costs involving the production of citrus nursery tree in a nursery
associated with Vivecitrus, with annual production capacity of 360,000 citrus
nursery tree, located in São Paulo, are shown in Table 5. The values used in the
composition of the costs were charged in 2014. In the final price, the citrus nursery
tree considered the very production of rootstocks and bud grafting, and 10%
disposal of the total annual production (36,000 citrus young plants). The fixed cost
considered depreciation of facilities (infrastructure) over 10 years, capital
opportunity cost invested 8% per year and total production of 3,240,000 citrus
young plants over this period (considering disposal of 360,000 citrus nursery tree
in 10 years).
Investment in infrastructure is high, but its contribution to the cost of production
is relatively low (4.8%), considering that its amortized over 10 years (Table 5). The
input items and manpower are the most important in the formation of citrus
nursery tree, totaling 78.5% of the production cost (Table 5). Among the inputs,
substrate and rootstock are the most important, accounting for 20.7% of the
production cost. Bud grafting and fertilizers represent 8.6% of the production cost.
Thus, maximizing the profitability of commercial nurseries can be achieved mainly
by reducing discharges of rootstocks and citrus nursery tree, as well as the efficient
use of the substrate and fertilizers. The costs involving manpower are the highest,
amounting to 48% of the total cost of production, since the operations are carried
out predominantly manually. Thus, the proper selection of employees and service
providers, training and continuous qualification of manpower, mechanisms aimed
at retaining talent and the automation of processes are critical to improving the
quality and efficiency of manual operations. Table 6 presents reference ranges
involving operating income from main operations in the production of citrus
nursery tree in greenhouse. In addition to the cost of production, the profitability
of the activity is determined by the market value of citrus nursery tree. Thus, when
planning the nursery, the producer must define what kind of market it wants to
serve, what is the level of demand in this market, and the size of it.
The Citrus Nursery Practices in Brazil 63
Table 5. Citrus nursery tree production cost located in the State of São Paulo with an annual production
capacity of 360,000 citrus nursery tree.
Description Unit Amount
23 Modules (8,0 x 60 m) +
Total (R$) Cost(R$
citrus nursery tree)
the cost of
Antechambers m² 11185 50.00 559,250.18 0.168 2.50%
Landscaping machine Hour 50 150.00 7,500.00 0.002 0.04%
Side screen m² 2517 3.50 8,808.19 0.003 0.04%
Plastic Cover m² 11380 4.50 51,210.41 0.015 0.25%
Central corridors (concrete) m² 41 220.00 8,937.50 0.003 0.04%
Cover ground m² 10567 2.70 28,531.51 0.009 0.14%
Grills m² 9754 22.00 214,596.00 0.064 1.06%
Blocks unit 24386 0.50 12,192.95 0.004 0.06%
(spray - shower”) 81,286.36 0.024 0.40%
Total of Infrastructure 972,313.11 0.292 4.82%
Drivermachine unit 2 22,171.05 44,342.09 0.123 2.04%
General service unit 30 21,624.58 648,737.29 1.802 29.80%
Administrative assistant unit 1 23,747.80 23,747.80 0.066 1.09%
Person in Charge unit 1 110,565.77 110,565.77 0.307 5.08%
Uniform Cleaning/Washing unit 1 22,170.69 22,170.69 0.062 1.02%
Night Watcher unit 1 27,874.46 27,874.46 0.077 1.28%
Gummosis Analysis Laboratory unit 1 23,747.80 23,747.80 0.066 1.09%
Administration Assistance unit 1 23,747.80 23,747.80 0.066 1.09%
General Administration 1 124,800.00 124,800.00 0.347 5.73%
Total of Manpower 1,049,733.71 2.916 48.22%
Nitrile glove unit 107 4.30 460.10 0.001 0.02%
White boots unit 72 22.00 1,584.00 0.004 0.07%
Uniform set unit 36 180.00 6,480.00 0.018 0.30%
Substrate unit 357660 0.71 253,938.60 0.705 11.66%
Bud grafting (Own Production)
unit 357660 0.30 107,298.00 0.298 4.93%
Rootstock Certificate (Own
Production) unit 357660 0.55 196,713.00 0.546 9.04%
Liquid fertilizer L 17031 2.44 41,556.62 0.115 1.91%
Slow-release fertilizer 220406 Kg 1788 16.20 28,970.46 0.080 1.33%
Fertilizer (Micronutrient) L 180 58.32 10,497.60 0.029 0.48%
Insecticides / Fungicides / Acaricides 1,447.754 0.004 0.07%
Methidathion L 12 33.38 400.56 0.001 0.02%
Abamectin L 6 40.82 244.92 0.001 0.01%
Carbendazin L 18 16.39 295.02 0.001 0.01%
Copper oxychloride Kg 26 10.00 259.20 0.001 0.01%
Carbosulfan L 6 38.28 248.05 0.001 0.01%
Fuel (2 tractors) L 4000 2.40 9,600.00 0.027 0.44%
Total of Material/Inputs 659,993.88 1.833 30.31%
Lease Month 12 3,500.00 42,000.00 0.117 1.93%
Employee Transport unit 12 9,000.00 108,000.00 0.300 4.96%
Chemical analysis unit 179 26.51 4,740.78 0.013 0.22%
Equipment maintenance 12 824.08 9,888.96 0.027 0.45%
Maintenance of plastic screen installation (33
Screens at each 2 years)
unit 17 1,200.00 19,800.00 0.055 0.91%
Electricity / Water Month 12 1,800.00 21,600.00 0.060 0.99%
Association Class / Union Month 12 567.00 6,804.00 0.019 0.31%
Miscellaneous expenses 12 535.92 6,431.04 0.018 0.30%
Transit Guide 179 42.69 7,634.25 0.021 0.35%
Other (Total) 226,899.04 0.630 10.42%
Vehicles (Depreciation15% p.y.)+insurance 1 35,000.00 7,000.00 0.019 0.32%
Expected fuel consumption3500km/month 350 3.10 17,360.00 0.048 0.80%
Marketing(Folders) 1 5,000.00 7,500.00 0.021 0.34%
Citrus nursery tree COST WITHOUT offtype disposal
Citrus nursery tree COST WITH offtype disposal (10%)
The Citrus Nursery Practices in Brazil 65
The more demanding, the greater should be the care and investment required in
the nursery, which can result in higher production costs, reduced profitability, if
there is no economy of scale of production and/or increase of added value of citrus
Table 6. Operating yield and average frequency of major manual operations to produce citrus
(plants or bags
Bag fulfillment / transport / placement on the countertop
Irrigation / fertigation
Classification and reassignment of rootstocks
Grafting and removing of rootstock
Removal of plastic tape
Thinning after grafting
Removal and delivery of citrus nursery tree
Source: Leandro Fukuda, 2012 (personal information).
BATAGLIA, O.C.; FURLANI, P.R.; FERRAREZI, R.S; MEDINA, C.L. Padrão Nutricional de Mudas
de Citros. Boletim Técnico Conplant/Vivecitrus. Araraquara: Conplant/Vivecitrus, August
de 2008. 40 p
BRASIL (País). Ministério da Agricultura, Pecuária e Abastecimento. Instrução Normativa n.
48, de 24 de September de 2013. Estabelecer as Normas de Produção e Comercialização
de Material de Propagação de Citros - Citrus spp., Fortunella spp., Poncirus spp., e seus
híbridos, bem como seus padrões de identidade e de qualidade, com validade em todo
o Território Nacional. Disponível em:
arLegislacaoFederal>. Visited on: December 15, 2013.
DONADIO, L.C. Variedades cítricas brasileira. In: Luiz Carlos Donadio, José Orlando de
Figueiredo e Rose Mary Pio. Jaboticabal: FUNEP, 1995, 228p. il.
CARVALHO, S..A.; GRAF, CC.D.; VIOLANTE, A.R. Produção de material básico e propagação.
In: MATTOS Jr., D. de; DE NEGRI, J.D.; PIO, R.M.; POMPEU Jr., J. (Ed.). Citros. Campinas:
Instituto Agronômico; Fundag, 2005. p. 279-316.
FUNDECITRUS. Fundo de Defesa da Citricultura. Manual de morte súbita dos citros.
Araraquara: Fundecitrus, 2006. 12 p.
OLIVEIRA, C.A. de.; PATTARO, F.C. Citros: Manejo de ácaros fitófagos na cultura. In:
YAMAMOTO, P.T. (Org.). Manejo Integrado de Pragas dos Citros. Piracicaba: CP 2, 2008.
OLIVEIRA, R. P.; SOARES FILHO, W. S.; PASSOS, O. S.; SCIVITTARO, W. B.; ROCHA, P. S. G.
Porta-enxertos para citros. Pelotas: Embrapa Clima Temperado, 2008. 45 p. (Embrapa
Clima Temperado. Documentos, 226).
PARRA, J.R.P.; LOPES, J.R.S.; ZUCCHI, R.A.; GUEDES, J.V.C. Biologia de Insetos-praga e
vetores. In: MATTOS Jr., D. de; DE NEGRI, J.D.; PIO, R.M.; POMPEU Jr., J. (Ed.). Citros.
Campinas: Instituto Agronômico; Fundag, 2005. p. 655-687.
PARRA-PEDRAZZOLI, A.L.; BENTO, J.M.S. Minador dos citros: bioecologia, comportamento,
controle biológico e manejo. In: YAMAMOTO, P.T. (Org.). Manejo Integrado de Pragas
dos Citros. Piracicaba: CP 2, 2008. p. 269-290.
POMPEU JUNIOR, J. Porta-enxertos. In: MATTOS JUNIOR, D.; DE NEGRI, J.D.; PIO,
R.M.;POMPEU JUNIOR, J. (Ed.). Citros. Campinas: Instituto Agronômico e Fundag, 2005.
RODRIGUES, J.C.V.; OLIVEIRA, C.A.L. de. Ácaros fitófagos dos citros. In: MATTOS JUNIOR, D.;
DE NEGRI, J.D.; PIO, R.M.;POMPEU JUNIOR, J. (Ed.). Citros. Campinas: Instituto
Agronômico e Fundag, 2005. p. 679-727.66
SÃO PAULO (Estado). Coordenadoria de Defesa Agropecuária. Portaria CDA n. 5, de 02 de
February de 2005. Estabelece normas de Medidas de Defesa Sanitária Vegetal e
The Citrus Nursery Practices in Brazil 67
Certificação de Conformidade Fitossanitária de Mudas Cítricas no Estado de São Paulo.
Visited on: August 20, 2012.
SÃO PAULO (Estado). Coordenadoria de Defesa Agropecuária. Portaria CDA n. 23, de 13 de
junho de 2005. Estabelece medidas de defesa sanitária vegetal aplicáveis ao cadastro de
Plantas Matrizes e de Borbulheiras de citros no Estado de São Paulo. Disponível
Visited on: August 20, 2012.
SCHÄFER, G.; BASTIANEL, M.; DORNELLES, A.L.C. Porta-enxertos utilizados na citricultura.
Ciência Rural, v.31, p.723-733, 2001.
SOARES, T. M. Desenvolvimento de três porta-enxertos cítricos utilizando águas salinas.
2003. 94p. Dissertação (Mestrado em Irrigação e Drenagem) – Escola Superior de
Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, 2003.
The Citrus Nursery Practices in Brazil 67
Accreditation of technician in charge in RENASEM (law10.711and decree
Producer enrollment with RENASEM–National Register of Seeds and
Seedlings (law 10.711 and decree5153).
Description of cultivars of which is the maintainer in National Registry of
Cultivars (RNC) (law 10.711 and law 5153).
Registration of Plant Providing Propagation Material (Seeds and bud
grafting) with validity of 5 years (Normative instruction N. 48).
Certification of Nursery (Normative instruction N.48).
Inspection Report: Budstocks: at least, in the pre-collecting of
budwoods (Normative instruction N.48).
Rootstocks: to 60 days after the plant emergency and in transplanting
or pre-trade of rootstock (Normative instruction N.48).
The budding: between 40 to 60 days after grafting and pre-marketing
(Normative instruction N.48).
a. Registration of Nursery, duly revalidated every three years by the
CDA – Department of Agriculture and Livestock Protection (CDA
b. Seeds and budwoods registration at CDA (Ordinance CDA 5).
c. Technical project of the nursery, including infrastructure systems
and equipment for the production, which shall include its very
operational capacity or of third-parties (law 5153, article 5, item II).
d. Commitment statement of technician in charge (law 5153, article 5).
e. Technical Project of production (law 5153, article 51)
f. Nursery inspection report (law 5153, article51 and CDA5, article7)
g. Production and trade maps of seeds, budwoods, citrus nursery tree (law
5153, article5 and Ordinance CDA5, article 7)–see item7.1.
h. Visits Record Book of Technician in Charge.
The nursery growers should also maintain the documentation of the established
duly regularized, according to the tax, social security and labor laws applicable at
federal, state or local level.
Source:Department of Agriculture and Livestock Protection of the State of São Paulo, 2013.
The Citrus Nursery Practices in Brazil 69
FLOWCHART OF PRODUCTION OF CITRUS NURSERY TREE
Source: Vivecitrus, 2012 (personal information).
and CCF Request
transport of citrus
Issuance the CFO,
request of PTV