Production of desert rose seedlings in different potting media

Abstract

Over the past decade the desert rose received fame in the flower market due to its striking and sculptural forms; however, the commercial production of these species is quite recent and little is known about its crop management, including substrates recommendation. The objectives of this study were to investigate the effect of different substrates on desert rose seed germination and production of its seedlings. Experiment I: freshly harvested seeds of desert rose were sown in different substrates e.g. sand, coconut fiber, semi-composted pine bark, sand + coconut fiber, semi-composted pine bark + sand and coconut fiber + semicomposted pine bark. These substrates were evaluated to study the emergence percentage of seeds, initial growth of seedlings and seedling emergence speed index (ESI). Experiment II: desert rose from the experiment I were transferred to plastic pots filled with the same substrates as in experiment I. The pH and electrical conductivity (EC) of the substrates were noted every 30 days while the growth parameters of seedlings were recorded after 240 days. Results from experiment I showed higher germination rate and seedling growth in substrates containing semi-composted pine bark. Similarly, in experiment II, better quality seedlings were observed in substrates containing semi-composted pine bark. Thus, for desert rose seed germination and seedling growth, it is recommended to use substrates containing semi-composted pine bark.

Full text

Production of desert rose seedlings in different Potting media250
V. 23, No. 3, 2017, p. 250-256
Production of desert rose seedlings in different potting media(1)
RONAN CARLOS COLOMBO(2)*, VANESSA FAVETTA(2), DEIVED UILIAN DE CARVALHO(2), MARIA APARECIDA DA
CRUZ(2), SERGIO RUFFO ROBERTO(2), RICARDO TADEU DE FARIA(2)
ABSTRACT
Over the past decade the desert rose received fame in the ower market due to its striking and sculptural forms; however,
the commercial production of these species is quite recent and little is known about its crop management, including substrates
recommendation. The objectives of this study were to investigate the effect of different substrates on desert rose seed germination
and production of its seedlings. Experiment I: freshly harvested seeds of desert rose were sown in different substrates e.g. sand,
coconut ber, semi-composted pine bark, sand + coconut ber, semi-composted pine bark + sand and coconut ber + semi-
composted pine bark. These substrates were evaluated to study the emergence percentage of seeds, initial growth of seedlings and
seedling emergence speed index (ESI). Experiment II: desert rose from the experiment I were transferred to plastic pots lled with
the same substrates as in experiment I. The pH and electrical conductivity (EC) of the substrates were noted every 30 days while
the growth parameters of seedlings were recorded after 240 days. Results from experiment I showed higher germination rate and
seedling growth in substrates containing semi-composted pine bark. Similarly, in experiment II, better quality seedlings were
observed in substrates containing semi-composted pine bark. Thus, for desert rose seed germination and seedling growth, it is
recommended to use substrates containing semi-composted pine bark.
Keywords: Adenium obesum, seeds, germination, Apocynaceae.
RESUMO
Produção de mudas de rosa do deserto em diferentes substratos
Na última década as plantas de rosa do deserto ganharam destaque no mercado de ores devido ao seu exotismo e formas esculturais;
contudo, a produção comercial dessa espécie ainda é recente e pouco se sabe sobre o manejo da cultura, incluindo a recomendação
de substratos. Assim, objetivou-se investigar o efeito de diferentes substratos na germinação das sementes e produção de mudas
de rosa do deserto. Experimento I: sementes recém-colhidas de rosa do deserto foram semeadas nos substratos: areia, bra de
coco, casca de pinus semi-compostada, areia + bra de coco, areia + casca de pinus semi-compostada e bra de coco + casca de
pinus semi-compostada. Os parâmetros estudados neste ensaio incluíram a porcentagem de emergência das sementes e índice de
velocidade de emergência (IVE), e o crescimento inicial das mudas. Experimento II: plantas de rosa do deserto provenientes do
experimento I foram transplantadas para potes plásticos preenchidos com os mesmos substratos empregados no experimento I. O
pH e a condutividade elétrica dos substratos (CE) foram medidos a cada 30 dias enquanto os parâmetros de crescimento foram
tomados depois de 240 dias de cultivo. No experimento I maiores porcentagens de germinação e crescimento das mudas foram
observados nos substratos contendo casca de pinus semi-compostada. Similarmente, no experimento II, mudas de melhor qualidade
foram encontradas nesses mesmos substratos. Assim, para a germinação de sementes e crescimento de mudas de rosa do deserto é
recomendado o emprego de substratos contento casca de pinus semi-compostada.
Palavras-chave: Adenium obesum, sementes, germinação, Apocynaceae.
DOI: http://dx.doi.org/10.14295/oh.v23i3.1139
(1)Received in 11/06/2017 and accepted in 10/08/2017.
(2)Universidade Estadual de Londrina, Departamento de Agronomia, Londrina-PR, Brazil. *Corresponding author: ronancolombo@yahoo.com.br.
Licensed by CC BY 4.0
Scientific article
1. INTRODUCTION
Adenium genus belongs to the botanical family
Apocynaceae, which includes many tropical ornamental
species such as Catharanthus spp., Beaumontia spp.,
Carissa spp., Allamanda spp., Mandevilla spp., Nerium
spp. and Plumeria spp. (COLOMBO et al., 2015). Adenium
obesum (Forssk.) Roem. & Schult. was found in the sub-
Saharan region of Africa, from Sudan to Kenya and west
of Senegal to south of Natal and Swaziland (DIMMITT
et al., 2009). These species are caudiciform, which
develops roots and/or swollen stem that serve as primary
organ to reserve water. The owers having ve sepals
and ve petals of various shades that are fused together
into a oral tube (DIMMITT et al., 2009; McBRIDE et
al., 2014). However, despite the great oral diversity, the
plant is mostly valued for the shape and development of
its caudex. The plant is commercialized in vases or other
similar containers in the form of seedlings or owering
plants. Therefore, to provide physical and chemical
support and to ensure better seed germination and seedling
development, the use of appropriate substrate is of utmost
importance for the production of these species on a large
scale.

RONAN CARLOS COLOMBO et al. 251
V. 23, No. 3, 2017, p. 250-256
Different types of substrates are being used for the
production of ornamental plants. But in order to obtain
satisfactory results, it is important to characterize its
physical and chemical properties, which play a key role
during the potting stages (PACHECO, 2006; SCHAFER
et al., 2008; SCHAFER et al., 2015). The proportions of
air/water of a substrate are determined by their physical
properties, mainly the density and porosity of each
material (KÄMPF et al., 2006; SANTOS et al., 2002;
SCHAFER et al., 2015). This property may directly
affect the seed germination, since the density and
porosity of the substrate are related to the availability of
water and air to the medium, and may provide greater or
lesser resistance to seedling emergence.
Among chemical properties of the material or mix
(substrate), pH and electrical conductivity (EC) holds great
importance (KÄMPF et al., 2006; LUDWIG et al., 2014).
Constant monitoring of these properties provides the
growers an overview of the salinization and acidication
of the growth medium, thus making it possible to
fertilize substrates without damaging of the growth of the
seedlings.
Kämpf et al. (2006) and Caballero et al. (2007) reported
that the pH of the substrates is directly related to the
availability of nutrients for plants, as well as by complexation
and adsorption nutrients reaction. Keeping in view the above
facts, this study was designed aiming to evaluate the effect
of organic and mineral substrates on seed germination
and seedling production of desert rose plants.
2. MATERIAL AND METHODS
The experiments were conducted between May to
August of 2014 (Experiment I) and from August to April
of 2015 (Experiment II) in greenhouse Van der Hoeven®,
which is covered with polycarbonate plates and humid
cooling system. When the internal temperature reaches
28 °C the cooling system is triggered on and is switched
off automatically when temperature reaches 26 °C. The
greenhouse is located at the Department of Agronomy in
the Londrina State University - UEL.
Experiment I
Freshly harvested seeds of Adenium obesum were
subjected to germination test at 25 °C, using four
replicates of 50 seeds, which were placed on blotting
paper moistened with distilled water 2.5 times the dry
matter of the paper (BRASIL, 2009), packed in crystal
polystyrene boxes (Gerbox®). The variables evaluated were
germination percentage and germination speed index (GSI)
(MAGUIRE, 1962); the counting was initiated three days
after installation. From this test, there was observed that
the germination percentage and GSI were 96% and 8.1,
respectively.
For the emergence test, a completely randomized
design was used with 4 replications and 40 seeds per
treatment. Seeds were sown in trays with 128 cells, lled
with the substrates: sand, coconut ber Amabra® 47,
semi-composted pine bark Lupa®, sand + coconut ber
Amabra® 47, semi-composted pine bark Lupa® + Sand,
and coconut ber Amabra® 47 + semi-composted pine
bark Lupa®. The sand had an average particle size of 0.2 -
0.6 mm and the substrates mixtures were prepared with a
ratio of 1:1 (v/v); substrates physicochemical characteristics
was evaluated according to Kämpf et al. (2006) (Table
1). Seedling emergence was recorded on daily basis until
it stopped. The recorded data was used to calculate the
emergence percentage and emergence speed index (ESI).
Table 1. Physical and chemical characterization of the substrates, based on apparent density (AD), water holding capacity
(WHC), pH and electrical conductivity (EC).
SubstratesaAD (g L-1) WHC (mL L-1) pH EC (mS cm-1)
S 1,380.0 527.1 6.8 0.1
CF 103.6 732.4 6.2 0.3
PB 274.4 378.7 4.7 2.3
S+CF 838.0 497.5 5.8 0.2
S+PB 1,026.0 441.0 7.2 1.9
CF+PB 273.3 486.3 6.7 1.7
aSubstrate: (S) sand, (CF) coconut ber, (PB) semi-composted pine bark, (S+CF) sand + coconut ber, (S+PB) sand + semi-composted pine bark and
(CF+PB) coconut ber + semi-composted pine bark.
After 90 days of last emergence, 10 plants from each
treatment with a total of 40 plants per replication, were used
to evaluate the different parameters e.g. number of leaves,
diameter of the caudex (mm), caudex and taproot length
(mm), fresh and dry matter (g) of roots, stems and leaves. The
data was subjected to analysis of variance (ANOVA) and
means compared by Tukey test at 5% probability level.
Experiment II
A. obesum plants from the rst experiment (see the plants
size in Table 2) were grown in black plastic pots with volume
of 0.4 L lled with the same substrates which the plants
germinated in experiment I. The pots were randomly placed
on a high bench (60 cm) and irrigated daily to maintain the
water holding capacity of the substrate between 80 and 90%.

Production of desert rose seedlings in different Potting media252
V. 23, No. 3, 2017, p. 250-256
The pH and electrical conductivity (EC) of the respective
treatments were recorded every 30 days using the leaching
method (KÄMPF et al., 2006), and every fth day after
these evaluation the plants were fertigated with Hoagland
solution at the rate of 50 mL per pot.
The plant growth was recorded after 240 days, on
the basis of shoot height (cm), caudex diameter (mm),
number of buds and dry matter of roots, stems and
leaves (g). The data from pH and EC of the substrates
were subjected to ANOVA and analyzed by polynomial
regression model. The variables related to plant growth
were submitted to ANOVA and means compared by
Tukey test at 5% probability.
3. RESULTS AND DISCUSSION
Experiment I
The effect of substrates on seedling emergence
percentage and emergence speed index (ESI) are
presented in Table 2. Lowest average values of emergence
percentage were recorded in the substrates of coconut
ber (CF) and sand + coconut ber (S + CF) compared
with other substrates, which promoted more than 91% of
germination. These results corroborate to the data obtained
in the germination test, in which there was observed 96% of
germination. Despite to have observed higher germination
for this species, if the chosen substrate is not adequate, the
germination percentage may be decreased.
Table 2. Emergence percentage (EM), emergence speed index (ESI), dry matter of roots (DMR), leaves (DML), stems
(DMS), number of leaves (NL), diameter of the caudex (DC), caudex length (CL) and taproot length (TRL) of Adenium
plants after 90 days of germination.
SubstrateaEM (%) ESI DMR (g) DML (g) DMS (g)
S 91 abb6.22 a0.013 d0.013 b 0.070 b
CF 84 b 4.09 b 0.023 bc 0.028 a0.117 ab
PB 97 a 5.45 ab 0.030 ab 0.028 a0.137 a
S+CF 83 b 4.92 ab 0.020 cd 0.020 ab 0.097 ab
S+PB 93 ab 5.61 ab 0.032 a 0.023 ab 0.127 a
CF+PB 98 a5.37 ab 0.018 cd 0.020 ab 0.107 ab
CV (%) 5.52 14.38 18.14 24.33 20.83
F 6.20** 3.55*13.80** 4.56** 4.42**
SubstrateaNL DC (mm) CL (mm) TRL (cm)
S 5.10 db9.61 c27.11 c4.84 ns
CF 7.20 b 10.34 bc 31.83 a4.74
PB 8.70 a11.26 a32.51 a5.19
S+CF 6.63 bc 10.41 abc 27.86 c5.24
S+PB 8.35 a10.57 ab 31.53 ab 4.74
CF+PB 6.13 c9.60 c29.21 bc 4.83
CV (%) 17.95 13.74 12.88 17.61
F 46.73** 7.87** 13.68** 2.78ns
aSubstrate: (S) sand, (CF) coconut ber, (PB) semi-composted pine bark, (S+CF) sand + coconut ber, (S+PB) sand + semi-composted pine bark and
(CF+PB) coconut ber + semi-composted pine bark. bMeans followed by the same letter do not differ by Tukey test at 5% probability. **, * Signicant
at 1 or 5% by F test, respectively.
Wagner Junior et al. (2006) reported that like
temperature, the substrate can also inuence the process of
imbibition and germination due to its effect on the water
potential and heat conduction capacity. Furthermore, the
seeds emergence occurs more unevenly when the substrate
is not ideal, which may be conrmed by the smaller ESI
values observed. The ESI in the sand substrate (6.2) was
closer to the GSI seen in the germination test (8.1) at 25 ºC
on paper. Though, smaller ESIs were expected than GSI,
since germination on paper is checked in advance; whereas
germination tests in trays with substrates, should expect the
seedlings emergence to record the germination.
Thus, the choosing of substrate should depend on the
seed requirements e.g. its size, water requirement, light
sensitivity and ease to handle seedlings count and other
evaluations (BRASIL, 2009). Lowest values of dry matter

RONAN CARLOS COLOMBO et al. 253
V. 23, No. 3, 2017, p. 250-256
of roots, caudex and leaves were recorded when sand
substrate was used, which is also similar to the values from
other substrates. The lowest values of these parameters
for the sand substrate might be due to the fact that it is
considered an inert material, and also during this period
there was not applied fertilizer to the substrate, resulting
in lowest dry matter of seedlings. Similar results were
observed for leaf number, length and diameter of caudex.
On the other hand, organic substrates pure or in
mixture, which consisted in semi-composted pine bark
e.g. Lupa® and coconut ber, tend to tolerate absence of
chemical fertilization for a longer period of time, ensuring
a satisfactory seedlings growth. Despite to have showed
similarity to others substrates, the semi-composted pine
bark promoted higher caudex growth in length and
diameter, as well as the number of leaves (Table 2). This
may be related to the physical characteristics of the
material (density = 274.4 g L-1 and retention capacity of
water = 378.7 mL L-1) and supply of some nutrients due to
its decomposition.
In contrast, the coconut ber is practically inert and
does not have the essential nutrients for the seedlings
development. However, it presents some unique physical
properties that make it a better choice, such as high
porosity (95.6%), higher water retention capacity (538 mL
L-1) and aeration (45.5%), along to some other advantages
as low cost and wide availability in the northeast region of
Brazil (CARRIJO et al., 2002).
The tap root length (Table 2) was not signicantly
affected by the substrates. This might have occurred
because of the seedlings were grown in suspended trays
with a hole beneath for excess water drainage, so the roots
might have ceased growth due to light and wind coming
through the hole. However, Pacheco et al. (2006) observed
that the substrates sand, vermiculite and coconut powder
provided greater root development for Myracrodruon
urundeuva seedlings.
Experiment II
After 240 days of seedlings planting on the same
substrates as used in the Experiment I, the seedlings were
evaluated aiming to determine the best substrate that can
be used for desert rose propagation during this period. The
number of shoots varied from 3.7 to 6 shoots per plant with
no signicant difference between the substrates (Table 3).
This is an important character, since each bud (branch) can
produce a whole inorescence providing higher market
value to the plant.
Table 3. Number of buds (NB), shoot height (SH), diameter of caudex (DC), dry matter of leaves (DML), stems (DMS)
and roots (DMR) of Adenium plants after 240 days of cultivation
SubstrateaNB SH (cm) DC (mm) DML (g) DMS (g) DMR (g)
S 3.71 ns 9.66 db31.90 c0.45 d3.12 c0.43 b
CF 6.00 12.93 bc 35.80 bc 1.01 bc 6.82 ab 1.14 ab
PB 3.88 15.71 b 35.48 bc 1.30 ab 7.82 a0.92 ab
S+CF 5.14 12.39 cd 32.45 c0.79 cd 4.18 bc 0.62 b
S+PB 4.29 14.71 bc 42.84 ab 1.27 ab 6.94 a 0.84 ab
CF+PB 5.71 19.29 a43.80 a 1.47 a 8.84 a1.55 a
CV (%) 49.00 13.10 12.73 25.32 27.39 50.64
F 1.20ns 22.07** 8.27** 14.40** 11.34** 5.10**
aSubstrate: (S) sand, (CF) coconut ber, (PB) semi-composted pine bark, (S+CF) sand + coconut ber, (S+PB) sand + semi-composted pine bark and
(CF+PB) coconut ber + semi-composted pine bark. bMeans followed by the same letter do not differ by Tukey test at 5% probability. ns: differences
not signicant. **Signicant at 1% by F test.
Based on the studied parameters the seedlings grown
on sand showed an overall lower growth rate, even before
fertilization of the substrate. The shoot height of plants grown
in coconut ber + semi-composted pine bark (CF + PB) was
found about double that of plants grown in sand (Table 3).
Maximum caudex diameter was observed in this same
substrate (CF + PB), as well as, in the substrate mixture
of sand + semi-composted pine bark. This is an important
feature, which provides the commercial and ornamental
value for the desert rose (COLOMBO et al., 2016).
The data relating to the dry matter of leaves, stems and
roots also indicate that the rate of plant growth is inuenced
by the substrates used (Table 3). The substrate mixture of
CF + PB resulted in the highest average variables (Figure
1F), hence it can be assumed that organic mixtures are
better suited to the organic-mineral (Figure 1B to D) for
desert rose growth, like shown in gure 1, whereas the
plants cultivated in sand presented a lowest development
(Figure 1A), even when submitted to fertigation. However,
these results are still contradictory, Colombo et al. (2016)
observed that desert rose grown on coconut ber + sand
(1:1, v v-1) and coconut ber + vermiculite (1:1, v v-1)
presented better growth rates. On the other hand, Alves et
al. (2016) found more effective results when desert rose
was grown on the mixture of decomposed pine bark + sand
(1:1, v v-1).

Production of desert rose seedlings in different Potting media254
V. 23, No. 3, 2017, p. 250-256
The availability of nutrients in organic substrates is
one of the main factors that inuences the plants growth.
However, it is noteworthy that this does not just depend on
the composition of the substrate, but also on the adsorption
capacity, pH, biological stability and presence of dissolved
organic compounds (CABALLERO et al., 2007). It can be
observed from the gure 2 (C, E and F) that EC showed
similar results in pine bark substrate and in its mixtures,
with a signicant decrease until 90 days of culture,
balancing and subsequently decreasing at the end of the
cycle. It is likely that the applied dosage of nutrient was not
suitable for desert rose, so that plants also absorbed ions
present in the substrates and led the EC values below 0.3
mS cm -1 for all the substrates.
Figure 1. Adenium plants growing on different substrates: (A) sand - S; (B) coconut ber - CF;
(C) semi-composted pine bark - PB; (D) sand + coconut ber - S+CF; (E) sand + semi-composted pine bark - S+PB and
(F) coconut ber + semi-composted pine bark - CF+PB, after 240 days of cultivation
Figure 2 - Variation of electrical conductivity in different substrates: (A) sand - S; (B) coconut ber - CF; (C) semi-
composted pine bark - PB; (D) sand + coconut ber - S+CF; (E) sand + semi-composted pine bark - S+PB and (F)
coconut ber + semi-composted pine bark - CF+PB, after 240 days of Adenium plants cultivation.

RONAN CARLOS COLOMBO et al. 255
V. 23, No. 3, 2017, p. 250-256
During the period of seedling cultivation, pH of pine
bark substrate and its mixtures were near to 8.0 (Figure
3), which according to Boaro et al. (2014) is common in
many organic substrates. They reported the pH and
electrical conductivity presenting values of 7.8 and
0.98 mS cm-1 respectively, for the composted substrate
of eucalyptus bark. The pH of substrates showed an
overall small uctuation during the cycle, tending to
decrease after 180 days of culture (data not shown). The
acidication of the substrates may have occurred due
to the plant growth and electrogenic pump activity,
H+-ATPase (YI-YONG et al., 2011). These results are
in conformity with Ludwig et al. (2014), who also
observed a decrease in pH of pine bark substrate that
turned semi-decomposed at the end of the cultivation
cycle of Gerbera jamesonii.
Figure 3 - Variation of pH on different substrates: (A) sand - S; (B) coconut ber - CF; (C) semi-composted pine bark
- PB; (D) sand + coconut ber - S+CF; (E) sand + semi-composted pine bark - S+PB and (F) coconut ber + semi-
composted pine bark - CF+PB, after 240 days of Adenium plants cultivation
It is also noteworthy here that the changes in the
substrates pH can occur even without cultivated plants on
it, but only with the water addition to the medium. Boaro et
al. (2014) found a pH change in cubic order, when eucalyptus
bark substrate was watered for over 80 days. Under these
circumstances, it is important to monitor the substrates pH
during the cultivation period, because the pH is resulted of
the relationship between substrate, water and plant.
4. CONCLUSIONS
The use of semi-composted pine bark as substrate is
recommended for seed germination and seedling growth
of desert rose. Although, sand substrate can ensure a good
germination for desert rose, but the substrate limits the
seedlings growth and reduces the nal quality of the seedlings.
AUTHORS CONTRIBUTIONS
R.C.C.: Creation of the idea, literature review, data
collection, laboratory analysis, statistical analysis of the
data, and manuscript writing. V.F.: Literature review,
data collection, laboratory analysis, manuscript writing.
D.U.C.: Literature review, data collection, laboratory
analysis, manuscript review. M.A.C.: Literature review,
data collection, laboratory analysis, manuscript review.
S.R.R.: Obtaining the funding and materials, orientation
and coordination of the study. R.T.F.: Creation of the
idea, obtaining the funding and materials, orientation and
coordination of the study, as well as, important suggestions
to the manuscript nal version.

Production of desert rose seedlings in different Potting media256
V. 23, No. 3, 2017, p. 250-256
REFERENCES
ALVES, G.A.C.; FREIRIA, G.H.; FURLAN, F.F.;
BERTONCELLI, D.J.; BARBOSA, A.P.; COLOMBO,
R.C.; FARIA, R.T.; MESCHEDE, D.K. Pilea microphylla
chemical control in desert rose production. International
Journal of Current Research, v.8, n.8, p.35624-35627,
2016.
BOARO, V.; SCHWARZ, S.F.; SOUZA, P.V.D.; SOARES,
W.; LOUROSA, G.V. Enxofre elementar no manejo do
pH de substrato orgânico alcalino. Ciência Rural, v.44,
p.2111-2117, 2014. DOI: <http://dx.doi.org/10.1590/0103-
8478cr20130768>
BRASIL - Ministério da Agricultura, Pecuária e
Abastecimento. Manual de análise sanitária de sementes.
Brasília: MAPA/Secretaria de Defesa Agropecuária, 2009.
399p.
CABALLERO, R.; ORDOVÁS, J.; PAJUELO, P.;
CARMONA, E.; DELGADO, A. Iron chlorosis in gerbera
as related to properties of various types of compost used
as growing media. Communications in Soil Science and
Plant Analysis, v.38, p.2357-2369, 2007. DOI: <http://
dx.doi.org/10.1080/00103620701588494>
CARRIJO, O.A.; LIZ, R.S.; MAKISHIMA, N. Fibra da
casca do coco verde como substrato agrícola. Horticultura
Brasileira, v.20, n.4, p.533-535, 2002.
COLOMBO, R.C.; FAVETTA, V.; YAMAMOTO, L.Y.;
ALVES, G.A.C.; ABATI, J.; TAKAHASHI, L.S.A.;
FARIA, R.T. Biometric description of fruits and seeds,
germination and imbibition pattern of desert rose [Adenium
obesum (Forssk.), Roem. & Schult.]. Journal of Seed
Science, v.37, n.4, p.206-213, 2015. DOI: <http://dx.doi.
org/10.1590/2317-1545v37n4152811>
COLOMBO, R.C.; FAVETTA, V.; MELO, T.R.; FARIA,
R.T.; SILVA, M.A.A. Potting media, growth and build-up
of nutrients in container-grown desert rose. Australian
Journal of Crop Science, v.10, n.2, p.258-263, 2016.
DIMMITT, M.; JOSEPH, G.; PALZKILL, D. Adenium:
Sculptural Elegance, Floral Extravagance. Tucson:
Scathingly Brilliant Idea, 2009. 152p.
KÄMPF, A.N.; TAKANE, R.J.; SIQUEIRA P.T.V.
Floricultura: técnicas de preparo de substratos. Brasília:
LK, 2006. 132p.
LUDWIG, F.; FERNANDES, D.M.; GUERRERO, A.C.;
BÔAS, R.L.V. Características dos substratos na absorção de
nutrientes e na produção de gérbera de vaso. Horticultura
Brasileira, v.32, n.2, p.184-189, 2014. DOI: <http://dx.doi.
org/10.1590/S0102-05362014000200011>
MAGUIRE, J.D. Speed of germination-aid in selection
and evaluation for seedling emergence and vigor. Crop
Science, v.2, n.1, p.176-177, 1962. DOI: <http://dx.doi.
org/10.2135/cropsci1962.0011183X000200020033x>
McBRIDE, K.M.; HENNY, R.J.; CHEN, J.; MELLICH,
T.A. Effect of light intensity and nutrition level on growth
and owering of Adenium obesum ‘Red’ and ‘Ice Pink’.
HortScience, v.49, n.4, p.430-433, 2014.
PACHECO, M.V.; MATOS, V.P.; FERREIRA, R.L.C.;
FELICIANO, A.L.P.; PINTO, K.M. S. Efeito de
temperaturas e substratos na germinação de sementes
de Myracrodruon urundeuva Fr. All. (Anacardiaceae).
Revista Árvore, v.30, n.3, p.359-367, 2006. DOI: <http://
dx.doi.org/10.1590/S0100-67622006000300006>
SANTOS, F.R.P.; CASTILHO, R.M.M.; DUARTE E.F.
Caracterização físico-química de sete componentes de
substratos recomendados para uso em oricultura. Cultura
Agronômica, v.11, p.81-92, 2002.
SCHAFER, G.; SOUZA, P.V.D.; KOLLER, O.C.;
SCHWARZ, S.F. Physical and chemical properties of
substrates to cultivate seedling of citrus rootstocks.
Communications in Soil Science and Plant Analysis,
v.39, p.1067-1079, 2008. DOI: <http://dx.doi.
org/10.1080/00103620801925547>
SCHAFER, G.; SOUZA, P.V.D.; FIOR, C.S. Um
panorama das propriedades físicas e químicas de substratos
utilizados em horticultura no sul do Brasil. Ornamental
Horticulture, v.21, n.3, p.299-306, 2015.
WAGNER JÚNIOR, A.; SANTOS, C.E.M.; SILVA, J.O.C.;
ALEXANDRE, R.S.; NEGREIROS, J.R.S.; PIMENTEL,
L.D.; ÁLVARES, V.S.; BRUCKNER, C.H. Inuência do
pH da água de embebição das sementes e do substrato na
germinação e desenvolvimento inicial do maracujazeiro
doce. Revista Brasileira de Agrociência, v.12, n.2, p.231-
236, 2006.
YI-YONG, Z.; JUAN, L.; HOU-QING, Z.; GAN,
L.; TING-JUN, D.; QI-RONG, S.; GUO-HUA, X.
Involvement of plasma membrane H+-ATPase in adaption
of rice to ammonium nutrient. Rice Science, v.18, n.4,
p.335-342, 2011. DOI: <https://doi.org/10.1016/S1672-
6308(12)60012-2>.