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Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
_______________________________________________
Submitted on December 28th, 2021 and accepted on June 29th, 2022.
1 This work is part of the master’s thesis of the rst author, nanced by FAPEMIG.
2 Universidade Federal de São João del-Rei, Programa de Pós-Graduação em Ciências Agrárias, Sete Lagoas, MG, Brazil. joelma_gon@yahoo.com.br; jcborges@ufsj.edu.br; anapaula@ufsj.edu.br;
louback@ufsj.edu.br
3 Embrapa (Empresa Brasileira de Pesquisa Agropecuária) Milho e Sorgo, Sete Lagoas, MG, Brazil. francisco.adriano@embrapa.br
*Corresponding author: jcborges@ufsj.edu.br
Production of edible owers: irrigation and biotechnology1
Joelma Gonçalves2, João Carlos Ferreira Borges Júnior2* , Francisco Adriano de Souza3, Ana Paula Coelho Madeira
Silva2, Leila de Castro Louback Ferraz2
10.1590/0034-737X202370020001
ABSTRACT
Garden pansy is a versatile gardening plant – it produces beautiful colorful edible-owers with high value in gourmet
cuisine. The use of irrigation and biotechnology in garden pansy cultivation can provide gains in ower productivity and
nutritional value. The goal of this study was to evaluate the growth and edible ower production in garden pansy plants,
submitted to dierent levels of irrigation and mycorrhizal inoculation. The experiment was conducted in randomized
blocks in the 2 x 5 factorial design, with the presence and absence of mycorrhizal inoculation in combination with 5
levels of irrigation with 6 replicates, in a greenhouse. There was no signicant interaction between the factors mycorrhizal
inoculation and irrigation levels by the F test. Under the tested conditions, the mycorrhizal inoculation was unable to
provide signicant changes in the growth, development and owering of garden pansy plants. It was concluded that no
symbiotic eciency was pointed out between the mycorrhizal fungus used and garden pansy plants. The best growth and
yield results for cultivating and producing edible owers of garden pansy were obtained at the 100% replenishment level
of water evaporation.
Keywords: Viola × wittrockiana; oriculture; water decit; mycorrhizal fungi.
INTRODUCTION
The market for edible-owers is growing world-wide as
it combines the beauty of the owers with health, function-
al foods and new trends in the gourmet cuisine (Reis et al.,
2004; Kinupp & Lorenzi, 2014). Thus, its growing demand
can mediate the economic development of ower produc-
ing countries, such as Brazil, through the identication of a
new market niche (Rivas-García et al., 2021).
The use of plants with edible owers to compose gardens
and landscapes are highly desirable, since the owers bring
not only beauty and balance to the environment, but they
are a great source of antioxidant compounds and essential
oils, being well appreciated in the high world gastronomy
(Kinupp & Lorenzi, 2014; Santos & Reis, 2021). The ed-
ible owers are highlighted, among functional foods, due
to the presence of bioactive compounds, which are capable
of neutralizing free radicals and contributing to a healthy
and balanced diet (Gonçalves et al., 2019b; Janarny et al.,
2021; Wu et al., 2022).
Edible owers of garden pansy (Viola × wittrockiana
Gams.) are considered one of the favorites to be used in
the elaboration and decoration of gourmet dishes, due to
their varied color combination, velvety texture and slightly
1
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
2Joelma Gonçalves et al.
sweet taste (Kinupp & Lorenzi, 2014). The evaluation of
agronomic procedures to improve the production and qual-
ity of the garden pansy is fundamental for development of
its market.
Water management is one key factors for ower produc-
tion. The growing pressure on the water resources implies,
in terms of agriculture, in the need to seek more ecient
irrigation management strategies. Water availability in the
root zone impacts agricultural production qualitatively
and quantitatively. About 97% of water uptake by the root
system is lost by transpiration on leaves surface due to the
continuous need for CO2 absorption (Taiz & Zeiger, 2013).
The water balance is a tool that can be applied to monitor
the adequacy of the water supply in the soil throughout the
crop cycle, as well as for the calculation of evapotranspira-
tion. Several studies have been devoted to evaluating crop
response to dierentiated strategies for water supply man-
agement (Arévalo et al., 2014; Álvarez & Sánchez-Blanco,
2015).
The use of biotechnology, especially arbuscular mycor-
rhizae (AMs), in plant production results in improvements
in the physiological processes, nutrition, growth, devel-
opment and protection of plants (Baum et al., 2015; Chen
et al., 2018). Favorability in the water-plant relationship
promoted by symbiosis with AMs can be considered the
second major benecial eect in plants after the nutritional
eect. AMs promote changes in leaf elasticity, elevate leaf
water potential and turgor, increase transpiration rate and
stomatal conductance, reduce root resistance and promote
root length and branching (Xu et al., 2018; Pavithra &
Yapa, 2018). However, a set of environmental factors,
and factors related to the host plant may interfere in the
formation, functioning and occurrence of AMs (Baum et
al., 2015; Chen et al., 2018; Kokkoris et al., 2019; Zhang
et al., 2019).
Many benets have already been reported due to the
use of AMs in the oriculture sector. The AMs can provide
better robustness and host quality, greater durability in pot
plants and less pollutants present in oral tissue and other
edible organs (Sun et al., 2021). In studies de Gonçalves et
al. (2019a), irrigation and mycorrhizal inoculation eects
interact in the production of total avonoids and anthocya-
nins of Garden pansy, cultivar Majestic Giants II Rosalyn.
The best results for total avonoids were observed when, in
the presence of mycorrhizae, 100% of the evaporated water
was replaced. For total anthocyanins, better results were
observed when, in the absence of mycorrhizae, 120% of the
evaporated water was replaced. Saini et al. (2019) observed
early owering in the combination of Funnelliformis mos-
seae, Acaulospora laevis and Pseudomonas uorescens,
and also better results for oral head size, ower fresh
and dry mass, total chlorophyll, carotene and phosphorus
content in plants of Gazania rigens.
Studies on the management of garden pansy edible
owers production are still scarce. Adequate management
of natural resources, especially water, as well as the use of
biotechnology to reduce the quantity of chemical inputs,
are relevant factors in the search for more ecient produc-
tion systems.
In this study, it was considered the hypothesis that
the factors water supply level and presence of arbuscular
mycorrhizae jointly inuence the plant growth and the crop
yield edible owers. The goal was to evaluate the growth
and production of edible owers of garden pansy plants
(Viola × wittrockiana Gams.) cultivar Majestic Giants II
Rosalyn, under dierent irrigation levels (120%, 100%,
80%, 60% and 40% of water evaporation replacement) and
presence or absence of mycorrhiza, in greenhouse.
MATERIALS AND METHODS
The experiment was carried out in a greenhouse at the
Federal University of São João del-Rei (UFSJ), in the mu-
nicipality of Sete Lagoas, Minas Gerais State, Brazil (19°
28’ 32” S, 44° 11’ 44” W). The experiment started with
sowing in May 2017 and ended in September 2017.
The experimental design was a randomized block with
a two x ve factorial scheme, with two levels of mycorrhi-
zal inoculation (absence and presence) and ve irrigation
levels (120%, 100%, 80%, 60% and 40% of evaporation
replacement) with six replicates. During the run of the
experiment, the temperature and the relative humidity of
the air were monitored, using a Digital Thermo-Hygrom-
eter, with measurement of internal, external, maximum
and minimum temperatures, and internal humidity, brand
Incoterm® model 7666.02.0.00.
The sowing was done in tray of small round tubes, with
a capacity of 55 cm3, dimensions: 12.5 cm height; 3.5 cm
outside diameter; 2.9 cm inside diameter; with six grooves
and 1 hole of 1 cm in diameter. The substrate used in the
sowing trays was composed of commercial vegetable land
(brand Terra de Minas) without mineral fertilization, plus
vermicompost (brand Adubos Bom Jardim), in the volu-
metric ratio of 3:1, previously homogenized, moistened and
solarized in a solar collector for disinfection of pathogens,
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
3
Production of edible owers: irrigation and biotechnology
through solar energy, for 24 hours at approximately 60 °C
(Ghini, 2004).
The seedlings transplant was done to common black
pots of polyethylene with a capacity of 3.1 L, dimensions
of 17 cm of height, 23 cm of diameter in the mouth and
14.5 cm of diameter in the base (mark Tetraplast), lined
with drainage blanket and placed on plates. Two plants
were transplanted per pot, constituting the experimental
units. The substrate used to ll the pots was composed of a
typical soil of the biome Cerrado, homogenized with sand
and organic matter, in the volumetric ratio of 2:1.5:0.5.
Prior to transplanting, the substrate was moistened and
solarized in a solar collector for disinfection of pathogens,
through solar energy, for 24 hours at approximately 60 °C
(Ghini, 2004). To ll the pots, the average mass of 2,255.45
g of substrate was used, with a standard deviation of 0.019
g. The substrate was submitted to physicochemical analysis
in the laboratory LABORSOLO (Paraná, Brazil) (Table 1).
Table 1: Physical-chemical characteristics of macro and micronutrients of the substrate used in the production of garden pansy (V.
wittrockiana) plants. Paraná, LABORSOLO, 2017
Analysis In Nature Dry Base (65 °C)
pH in CaCl2 0.01m 7.17
Electric conductivity (μS/cm) 1.865x10³
Humidity lost at 65 °C (%) 24.08
WHC - Water holding capacity (%) 10.07 13.26
CEC - Cation exchange capacity (mmolc kg-1) 136.00 179.14
Total phosphorus - P (mg kg-1) 1.99 2.62
Total potassium - K+ (mg kg-1) 243.20 320.34
Total calcium - Ca++ (mg kg-1) 175.80 231.56
Total magnesium - Mg++ (mg kg-1) 64.58 85.06
Total sulfur - S (mg kg-1) 48.32 63.65
Total copper - Cu++ (mg kg-1) 0.02 0.03
Total iron - Fe++ (mg kg-1) 1.03 1.36
Total manganese - Mn++ (mg kg-1) 0.00 0.00
Total zinc - Zn++ (mg kg-1) 0.01 0.01
The seeds used were garden pansy (Viola × wittrockiana
Gams) cultivar Majestic Giants II Rosalyn, F1 generation,
germination 93%, physical purity 99.9%, category S2 hy-
brid, lot 99.173, origin Japan, commercially acquired from
the company Sakata®. Three seeds per cell were sown. The
agronomic germination started at nine days after sowing
(DAS) and at 21 DAS the thinning of the seedlings was
performed. Deformed and low development seedlings were
removed, leaving only one per tube. At 52 DAS, transplan-
tation was performed for the denitive pots, with 2 plants
per pot.
The soil inoculum, containing fungus Claroideoglomus
etunicatum CNPMS09 (W.N. Becker & Gerd.) C. Walker
& A. Schüßler, was obtained from the Nucleus of Applied
Biology (NBA) of Embrapa Milho e Sorgo. This research
is registered in the SISGEN under the number A894B2E
for the access to Brazilian genetic patrimony - fungus - C.
etunicatum, in compliance with Law nº 13,123/2015 and
its regulations.
The inoculant based on inoculum soil was added to the
substrate of the sowing trays in the proportion of 20% of the
substrate volume, according to treatments, on the same day
of sowing. To equilibrate the microbiota of the substrate of
the seed trays, 1 mL of the inoculum suspension ltrate was
added to each tube.
The evaluation of the mycorrhizal colonization rate and
the quantication of spore density was performed at the end
of the experiment. These analyzes were carried out at the
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
4Joelma Gonçalves et al.
Microbial Molecular Ecology Laboratory of the Applied
Biology Center, Embrapa Milho e Sorgo. The mycorrhizal
colonization rate was estimated using the magnied grid-
line intersection method (Giovanetti & Mosse, 1980). The
structures that characterize the mycorrhizal association,
such as hyphae, arborescence, and vesicles, were quantied
in fragments of the pansy roots using a stereomicroscope
model Zeiss SV11. The number of arbuscular mycorrhizal
fungal spores was determined in 50 g of substrate sample
collected from pots.
Irrigation was done using the water provided by the
municipal water supply service. During the seedling
production period and during the establishment period,
stipulated as up to eigth days after transplanting (DAT), it
was irrigated to ll 100% of the water retention capacity
of the substrate. At 60 DAS (9 DAT) the application of
dierent levels of irrigation was started according to the
measurement of the water evaporation from the pots with
uncultivated soils (monitoring pots) by using the weighing
method. Then, daily manual irrigation was performed, ap-
plying 120%, 100%, 80%, 60% and 40% of the evaporation
volume.
The evaporation volume was measured in three mon-
itoring pots, which were weighed daily in an analytical
balance with a capacity of 5 kg and an accuracy of 0.01 g.
The monitoring pots, lled with substrate up to about 5 cm
below the border, were previously saturated by capillarity.
The upper faces of the monitoring pots were covered with
plastic lm to prevent evaporation during the period of
saturation and subsequent monitoring of the decreasing
drainage rate. In this period, the pots were removed from
the tray and placed suspended to allow percolation of
excess water. After 24 hours, when no percolation drip
occurred in an interval of approximately 30 minutes, it was
considered that the water holding capacity (pot capacity)
had been reached. Then, the plastic lms placed on the up-
per surface of the monitoring pots were removed, allowing
the evaporation process.
The loss of water by evaporation in the monitoring pots
was determined by means of the water balance equation,
according to the expression:
1ii
a
MM
Ev D
ρ
+
−
= − (1)
Where Ev is the evaporation occurring in the monitor-
ing pot at a time interval (mL); Mi is the total mass of the
monitoring pot at the beginning of the interval (g); i is the
index representing the instant considered for the balance;
Mi+1 is the total mass of the monitoring pot at the end of
the interval (g); D is the drainage (percolation), which
eventually occurred in the time interval (cm3) and ρa is
the water density (1 g cm-3). The volume of water lost by
evaporation in monitoring pots was relled daily to reach
the pot capacity. Percolation events were recorded.
The variables height (H), number of leaves per plant
(NL), base diameter (BD), shoot fresh weight (SFW),
shoot dry weight (SDW), leaf area (LA), root fresh weight
(RFW), root dry weight (RDW), root to shoot fresh weight
ratio (RSFWR), and root to shoot dry weight ratio (RS-
DWR) were evaluated at the end of the experiment (115
DAS. Digitally recorded leaf images were used to calculate
the total leaf area (cm2) using the ImageJ® software. Shoot
fresh and dry weight were determined by weighing in a
precision analytical balance (0.0001 g). The height (H) and
the base diameter (BD) were measured with a digital cal-
iper. The number of leaves per plant (NL) were measured
by manual counting. The dry matter was determined after
drying in an oven with forced air circulation, for 72 hours
at 70 ± 5 °C, or until it reached constant weight (Lopes &
Lima, 2015).
Flowers were collected totally open weekly in the early
morning to evaluate the production. The parameter product
of oral dimensions, here proposed as the product between
the width and height dimensions of owers, and fresh and
dry weight of the owers were measured during the ow-
ering start period until the nal period of the experiment,
which occurred between 76 and 111 DAS.
Experiment was conducted in a two x ve factorial,
completely randomized block design, with six replicates,
at the 5% level of signicance. A block design was used
due to the staggering of the experiment. Normality and
homoscedasticity assumptions were veried by applying
Lilliefors and Levene tests, respectively. When variables
studied did not meet the assumptions of the statistical
model, a Box Cox transformation (Box & Cox, 1964)
was applied. Transformed variables were again veried to
check the assumptions of the statistical model. The analysis
of variance was then performed.
When a signicant interaction between the factors
studied was observed, the unfolding was performed. The
regression analysis at the 5% level of signicance was
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
5
Production of edible owers: irrigation and biotechnology
performed for the quantitative factor (irrigation level)
when a signicant dierence was identied by the F-test.
The ExpDes.pt package was used in the software R (R
Development Core Team, 2021).
RESULTS AND DISCUSSIONS
The means of maximum, minimum and mean daily
temperatures during the execution period were 33.2 °C,
13.8 °C and 23.5 °C, respectively. The means of maximum,
minimum and mean daily air relative humidity were 81.1%,
29% and 55%, respectively. The physical-chemical analy-
sis of the substrate used for garden pansy plants production
presented low phosphorus content, which was already
expected due to the type of soil used (Table 1).
The results of the analysis of variance are presented in
tables 2 and 3. For the roots of the plants, the colonization
rate presented a mean value of 32% of colonized root
fragments for the plants that received the inoculant and 0%
of colonization for the plants that did not receive inoculant.
A mean of 224 spores per 50 g of substrate was quantied
for the pots that received inoculant material. Spores were
found only in the treatment that received mycorrhizal
inoculation plus 120% of water evaporation replacement
(Figure 1).
Table 2: ANOVA the rate of colonization (RC); height (H); number of leaves (NL); shoot fresh weight (SFW); shoot dry weight
(SDW); leaf area (LA); base diameter (BD); root fresh weight (RFW); root dry weight (RDW); root to shoot fresh weight ratio
(RSFWR); root to shoot dry weight ratio (RSDWR) of garden pansy (V. wittrockiana) plants, produced under greenhouse conditions
under a mycorrhizal inoculation (M) factor and irrigation factor (I) at 115 DAS. Sete Lagoas, UFSJ, 2017
MS
F.V G.L RC (%) H (cm) NL
SFW
(g)0.14
SDW
(g)
LA
(cm²)0.30
BD
(mm)
RFW
(g)
RDW
(g)
RSFWR RSDWR
Blocos 5 128.90 5.1036 510.50 0.004 1.010 0.222 0.140-7.022 0.061-0.021-0.008-
Mycorrhiza 114978.40-3.9578 851.30 0.001 0.015 0.473 0.435* 44.582* 0.195* 0.367* 0.058*
Irrigation 4 1085.40-28.9085* 13615.60* 0.220* 8.011* 9.453* 1.736* 55.507* 0.226* 0.092* 0.020*
M*I 4 1085.40* 1.6013 438.40 0.001 0.078 0.092 0.213-2.908 0.019-0.015-0.005-
Erro 45 52.70 1.5752 497.50 0.004 0.461 0.277 0.101-4.762 0.038-0.026-0.006-
C.V (%) 45.93 10.92 27.11 4.73 31.95 9.66 11.98 39.66 39.35 36.00 30.64
SFW and LA Cox Box transformation (λ = 0.14 and λ = 0.30, respectively). (*) Signicant eect by the F test at the 5% of signicance.
Table 3: ANOVA the product of oral dimensions (PFD), ower fresh weight (FFW), ower dry weight (FDW) and ower production
(PROD) of garden pansy (V. wittrockiana) plants, produced under greenhouse conditions under a mycorrhizal inoculation (M) factor
and irrigation factor (I) at 115 DAS. Sete Lagoas, UFSJ, 2017
MS
F.V G.L
PFD
(cm²)
FFW
(g plant-1)
FDW
(g plant -1)0.1
PROD
(owers plant-1)
Blocos 5 28.89 9.784 0.0149- 6.54
Mycorrhiza 1104.57 2.429 0.0030- 2.60
Irrigation 4 1029.99* 121.905* 0.0766* 135.40*
M*I 4 10.57 3.144 0.0024- 2.68
Erro 45 43.84 4.285 0.0013- 8.97
C.V (%) 13.17 35.23-3.67 37.94
FDW Cox Box transformation (λ = 0.1). (*) Signicant eect by the F test at the 5% of signicance.
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
6Joelma Gonçalves et al.
In relation to irrigation, the rate of colonization (RC)
increased as the water availability increased in the pots.
With a quadratic tendency, the lowest colonization rate
occurred with the replacement of 42.44% of the evaporated
water (Figure 2).
The absence of mycorrhizal colonization in treatments
that did not receive inoculant indicated that the method of
exposition of the substrate to the solar energy was eective
in the elimination of propagules of native fungi. However,
the rate of colonization found in the plants (32%) receiving
inoculant is dierent from those reported in the literature.
Zubek et al. (2015) found a colonization rate above 80% in
Viola tricolor, using a mix of Rhizophagus irregulares and
Funneliformis mosseae.
Figure 1: Root fragments free of mycorrhizal colonization (A); unit of mycorrhizal infection with presence of hyphopodia (*) and
arbuscules (**) (B); spores (C. etunicatum) extracted from the substrate of the growing pots (C, D) of garden pansy (V. wittrockiana)
plants. Sete Lagoas, EMBRAPA, 2017.
Figure 2: Rate of colonization (RC) in the root system of garden pansy (V. wittrockiana) plants submitted to dierent levels of irriga-
tion, during production in a greenhouse. Sete Lagoas, UFSJ, 2017.
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
7
Production of edible owers: irrigation and biotechnology
The relatively low values of the colonization rate are
probably due to a low symbiotic responsiveness of the host
plant to the fungus used. Symbiotic responsiveness varies
in relation to host plant species, mycorrhizal fungus spe-
cies and environmental conditions. In this way, it presents
dierent values for each situation (Moreira & Siqueira,
2006; Smith & Read, 2008). On the other hand, the low
colonization rate may indicate that the substrate used
did not present adequate conditions for the development
of mycorrhization, possibly due to the pH in the alkaline
range allied to the low availability of nutrients (Table 1).
It should be noted that the strain CNPMS09 was isolated
from slightly acid soil and with built fertility.
The higher water availability favored higher rates of
mycorrhizal colonization (Figure 2), since the mycorrhizae
present better development near to the eld or pot capacity,
as it happens for vegetal (Moreira & Siqueira, 2006). The
presence of spores in the treatment that received the highest
replacement of water evaporation suggests that the fungus
found conditions favorable to sporulation only in this
treatment (Smith & Read, 2008), for which the highest col-
onization rate was found and probably the highest fungal
biomass to support sporulation occurred.
The variations between the water replacement volume
values of the three monitoring pots were negligible, which
indicates the consistency of the method used to quantify the
evaporation. The maximum, medium and minimum values
of water replacement in the monitoring pots were 145.8;
82.4 and 39.4 mL, respectively. During the experiment
period, there was a need for adjustments of the pot capac-
ity due to the loss of water retention capacity. The mass
reduction for the pot capacity was, on average, 183 g. The
mean daily volume of water applied in the experimental
units according to irrigation levels equivalent to 120%,
100%, 80%, 60% and 40% of evaporation (EV) during the
experiment was 102, 85, 68, 51 and 34 mL, respectively.
There was percolation in the pots that received 120%
and 100% replacement of the water evaporation. Then, an
adjustment procedure was performed on the pot capacity
reference. The adjustment was made by discounting the
excess percolation depth observed at the 100% evaporation
level. The largest percolated water volume occurred in the
initial period of vegetative growth. With the growth of
the plants and adjustment of the water retention capacity
reference in the monitoring pots, there was a reduction in
percolated volume in the experimental units that received
the 120% level and there was no more percolation in the
experimental units that received the 100% replenishment
level of the evaporation of water, indicating that the added
volume of water was consumed almost entirely in the
evapotranspiration process.
The reduction of the water retention capacity in the
monitoring pots was possibly due to the degradation of the
organic matter present in the substrate. Fresh bovine manure
presents readily decomposable material, such as proteins,
starch and cellulose. These chemically unstable substances
are easily attacked by decomposers microorganisms, which
leads to the process of degradation or mineralization of the
organic matter and to the volume reduction (Moreira &
Siqueira, 2006). Allied to this, it is possible that preferen-
tial paths for water inltration through the substrate of the
monitoring pots may have arisen due the degradation of the
organic matter and accommodation of the material.
The growth of garden pansy plants was analyzed at the
end of the experiment period (115 DAS). For the observed
variables height (H), number of leaves per plant (NL), base
diameter (BD), shoot fresh weight (SFW), shoot dry weight
(SDW), leaf area (LA), root fresh weight (RFW), root dry
weight (RDW), root to shoot fresh weight ratio (RSFWR),
and root to shoot dry weight ratio (RSDWR) there was no
signicant eect of the interaction between mycorrhizal
inoculation factors and irrigation levels by the F test at the
5% of signicance. Therefore, the factors were evaluated
separately for these variables.
The mycorrhizal inoculation factor showed a signicant
dierence in the root system variables, root to shoot ratio
and base diameter (RFW, RDW, RSFWR, RSDWR and
BD). The other studied variables of the aerial part showed
no dierence between the levels of the mycorrhizal inocu-
lation factor (Table 4).
In the nal growth analysis of garden pansy plants,
the increase observed in the root-shoot ratio (Table 4)
reinforces the hypothesis that the substrate had low levels
of available nutrients. In this condition, the plant displaces
photoassimilates into the root system with the aim of in-
creasing the capitation of nutrients. In Azalea the increase
in nitrogen (N) fertilization rate signicantly promoted
shoot growth, and low N and phosphorus (P) fertilization
promoted root growth and nutrient acquisition eciency
(Ristvey et al., 2007).
Higher mass values found in roots colonized with AMs
have also been observed in studies with Gazania splen-
dens, Dimorphoteca sinuata (Püschel et al., 2014) and
Calendula ocinalis (Heitor et al., 2016). This eect can
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
8Joelma Gonçalves et al.
be explained by the presence of intra-root mycelia, whose
biomass represents up to 20% of the weight of the roots
(Smith & Read, 2008).
Non-signicant eects of mycorrhization on the
aerial part of inoculated plants have also been reported
in the production of Sanvitalia procumbens, Impatiens
hawkerii (Püschel et al., 2014), Viola. tricolor (Zubek et
al., 2015), Tagetes patula and Salvia splendens (Janowska
& Andrzejak, 2017). This fact may have occurred due to
the low symbiotic eciency, which varies according to
the dierent species of AMs, host plant and environmental
conditions (Moreira & Siqueira, 2006) and, in this way, did
not provide benets to the aerial part of the garden pansy
even with the colonization eected.
Table 4: Mean height (H); number of leaves (NL); shoot fresh weight (SFW); shoot dry weight (SDW); leaf area (LA); base diameter
(BD); root fresh weight (RFW); root dry weight (RDW); root to shoot fresh weight ratio (RSFWR); root to shoot dry weight ratio
(RSDWR) of garden pansy (V. wittrockiana) plants, produced under greenhouse conditions under a mycorrhizal inoculation factor:
without mycorrhizal inoculation (NM) and with mycorrhizal inoculation (M) at 115 DAS. Sete Lagoas, UFSJ, 2017
Micorrhizal
inoculation
H
(cm) NL SFW
(g)0.14
SDW
(g)
LA
(cm²)0.30
BD
(mm)
RFW
(g)
RDW
(g) RSFWR RSDWR
NM 11.84 a 79 a 1.40 a 2.17 a 5.35 a 2.57 b 4.64 b 0.44 b 0.37 b 0.21 b
M 11.24 a 86 a 1.41 a 2.11 a 5.54 a 2.74 a 6.36 a 0.55 a 0.53 a 0.28 a
Means followed by the same letter in the column do not dier by the F test at the 5% level of signicance. SFW and LA Cox Box transformation (λ =
0.14 and λ = 0.30, respectively).
In addition, the low content of P and other nutrients
(Table 1) on the substrate was possibly not enough to
stimulate the action of mycorrhizae. In soils with very low
fertility, such as typical Cerrado soils, which were used
for substrate composition, the addition of small amounts
of P may favor the eect of inoculation on plant growth
(Moreira & Siqueira, 2006).
However, positive results in the growth and devel-
opment of ornamental plants inoculated with AMs are
reported in works with Viburnum tinus (Gómez-Bellot et
al., 2015); Cyclamen purpurascens (Rydlová et al., 2015);
Sinningia speciosa (Janowska et al., 2016) Rudbeckia
laciniata and Solidago gigantea (Majewska et al., 2017);
Calendula ocinalis (Kheyri et al., 2022).
Signicant dierences were detected on the variables
of plant growth at the end of the experiment in response
to the irrigation levels. A linear eect was observed for the
variables SDW, RFW, H and NL, indicating that for each
1% of water evaporation, there was growth of 0.025 g;
0.064 g; 0.046 cm and 1.018 units, respectively (Figure 3).
For the variables SFW, RDW, BD and LA, quadratic
behavior was observed, with points of maximum vegetative
growth in water replenishment of 107.1%; 96.8%; 104.8%
and 116.2% EV (Figure 4).
The reduction of plant biomass veried in garden pansy
plants in response to low irrigation levels (Figure 3 and
Figure 4) have also been observed by Cirillo et al. (2017)
in Bougainvillea production, in which, in addition to the
decrease in plant biomass, morpho-physiological changes
in response to the irrigation decit also occurred. The
same situation was observed Ugolini et al. (2015) when
evaluating the production of Viburnum opulus and Photinia
× fraseri under water decit, outdoors and in a greenhouse,
that found higher vegetative growth for treatment in
which 100% of the crop evapotranspiration determined
the water replacement quantity. Elansary et al. (2016),
in the production of Spiraea nipponica and Pittosporum
eugenioides, and Álvarez & Sánchez-Blanco (2013; 2015),
in the production of Callistemon citrinus and Callistemon
laevis, also obtained similar responses in relation to low
water availability.
The gain of plant biomass is closely linked to the water
availability to the crops, since cell growth only occurs due
to turgor tension, exerted by the water inside, guaranteeing
the expansion of the cell wall, its growth in extension
and the cell division. In addition, a number of metabolic
processes are aected by water deciency, such as stomatal
closure, nutrient absorption, and the metabolism of proteins
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
9
Production of edible owers: irrigation and biotechnology
and amino acids, which impedes the correct cellular func-
tioning and, therefore, the vegetal growth (Taiz & Zeiger,
2013; Lopes & Lima, 2015).
A linear downward eect was observed for RSFWR and
RSDWR variables, indicating that for each 1% of water
evaporation replacement, there was a decrease of 0.003 g
and 0.001 g in the ratio of fresh and dry biomass between
root and shoot, respectively (Figure 5).
Figure 3: Evaluation of shoot dry weight (SDW); root fresh weight (RFW); height (H) and number of leaves/plant (NL) of garden
pansy (V. wittrockiana) plants versus levels of irrigation at 115 DAS. Sete Lagoas, UFSJ, 2017.
Figure 4: Average of shoot fresh weight (SFW); root dry weight (RDW); base diameter (BD) and leaf area (LA) of garden pansy (V.
wittrockiana) plants versus levels of irrigation at 115 DAS (SFW and LA Box Cox transformation, λ = 0.14 and λ = 0.30, respectively).
Sete Lagoas, UFSJ, 2017.
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
10 Joelma Gonçalves et al.
Figure 5: Evaluation of the root to shoot fresh weight ratio (RSFWR) and root to shoot dry weight ratio (RSDWR) of garden pansy (V.
wittrockiana) plants versus levels of irrigation. Sete Lagoas, UFSJ, 2017.
One of the plant strategies to mitigate the possible
damages caused by the lack of water is the root growth,
allowing greater exploitation of the soil in search of water
(Lopes & Lima, 2015). This action was observed in garden
pansy plants, which presented higher values of RSFWR
and RSDWR when they had less water availability (Figure
5-a, b, respectively). The same occurred in studies with
Callistemon citrinus (Álvarez & Sánchez-Blanco, 2013)
and Viburnum opulus and Photinia x fraseri (Ugolini et al.,
2015).
The ower production, with the variables product of
oral dimensions (PFD), ower fresh weight (FFW), ow-
er dry weight (FDW) and production (PROD), evaluated
at the end of the experiment (115 DAS), did not present a
signicant interaction, by the F test at the level of 5% of
signicance, between the factors mycorrhizal inoculation
and irrigation levels. Therefore, the factors were evaluated
separately.
Regarding the mycorrhizal inoculation factor, there was
no signicant dierence between their levels in the ow-
ering variables (Table 5). However, signicant dierences
were observed in the owering variables of the garden
pansy plants for the irrigation levels. The performance pre-
sented in the reproductive stage of the pansy plants reects
what occurred in the vegetative growth phase.
The observed results show increases in PFD according
to the greater availability of water for the plants, following
a linear tendency with an increase of 0.289 cm² in each 1%
of the EV that was restored (Figure 6-a). For the variables
of PROD, FFW and FDW, quadratic tendencies were ob-
served, with maximum production and oral growth points
at 98.9% (10.8 owers plant-1), 111.8% (8.1 g plant-1), and
103.8% (1.1 g plant-1) EV, respectively (Figure 6-b, c, d).
The lack of inuence of mycorrhizal inoculation on
ower production has already been reported in studies with
Gazania splendens, Capsicum annuum, Sanvitalia pro-
cumbens, Pelargonium peltatum and P. zonale (Püschel et
al., 2014). Probably, the low responsivity of garden pansy
(V. wittrockiana) to the fungus C. etunicatum in relation to
plant growth was reected in the reproductive phase.
Table 5: Evaluation of product of oral dimensions (PFD), ower fresh weight (FFW), ower dry weight (FDW) and ower production
(PROD) of garden pansy (V. wittrockiana) plants in response to the mycorrhizal inoculation factor: without mycorrhiza (NM) and with
mycorrhiza (M), produced in a greenhouse (FDW transformation Box Cox with λ = 0.1). Sete Lagoas, UFSJ, 2017
Mycorrhizal
Inoculation
PFD
(cm²)
FFW
(g plant-1)
FDW
(g plant-1)0,1
PROD
(owers plant-1)
NM 51,61 a 6,08 a 0,98 a 8,10 a
M 48,97 a 5,67 a 0,96 a 7,68 a
Means followed by the same letter in the column do not dier by the F test at the 5% level of signicance. SFW and LA Cox Box transformation (λ =
0.1).
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
11
Production of edible owers: irrigation and biotechnology
Figure 6: Evaluation of product of oral dimensions (PFD), ower production (PROD), ower fresh weight (FFW) and ower dry
weight (FDW) of garden pansy (V. wittrockiana) plants versus levels of irrigation (FFW transformation Box Cox with λ = 0.10). Sete
Lagoas, UFSJ, 2017.
On the other hand, irrigation positively inuenced the
production of garden pansy owers (Figure 6). Similar
results were found by Aleman & Marques (2016) that
observed increase in the dry matter production of ower
buds of Chamomilla recutita for higher irrigation levels.
Plants cultivated under suitable water availability tend
to present higher nutrient absorption capacity and photosyn-
thetic rate, which enhances the vegetative and reproductive
growth (Taiz & Zeiger, 2013; Lopes & Lima, 2015). Under
the conditions of the experiment, higher water availability
resulted in greater average values of vegetative growth and
of the owering variables studied, indicating the relevance
of irrigation management.
Here we showed that irrigation is fundamental for the
production of garden pansy owers. At the commercial lev-
el, cost ecient irrigation systems can be implemented and
they might guarantee a stable production of garden pansy
owers. The results showed no eect of the mycorrhizal
inoculation on the production of garden pansy owers.
However, they reinforce the need for additional research
applied to the use of dierent strains of AM fungi and other
microbes (Saini et al., 2019), seeking to increase the e-
ciency of water and nutrient extraction and, consequently,
to achieve higher crop yields in oriculture.
CONCLUSIONS
The factors mycorrhizal inoculation and irrigation act
independently in vegetative growth and ower production
of garden pansy (V. wittrockiana) plants, cultivar Majestic
Giants II Rosalyn. There were no signicant increases in
the growth and production of owers in response to inocu-
lation with mycorrhizal fungi Claroideoglomus etunicatum
CNPMS09, even obtaining eective colonization and
reproduction of the fungus. Better growth and yield results
were obtained when irrigated with 100% replenishment
volume of water evaporation, which indicates water stress
for lower irrigation depths.
ACKNOWLEDGEMENTS, FINANCIAL
SUPPORT AND FULL DISCLOSURE
To FAPEMIG (Foundation for Research Support of
the State of Minas Gerais) for granting a scholarship. The
authors declare no nancial or other competing conicts
of interest.
REFERENCES
Aleman CC & Marques PAA (2016) Irrigation and organic fertilization
on the production of essential oil and avonoid in chamomile. Revista
Brasileira de Engenharia Agrícola e Ambiental, 20:1045-1050.
Álvarez S & Sánchez-Blanco MJ (2013) Changes in growth rate, root
morphology and water use eciency of potted Callistemon citrinus
Rev. Ceres, Viçosa, v. 70, n. 2, p. 1-12, mar/apr, 2023
12 Joelma Gonçalves et al.
plants in response to dierent levels of water decit. Scientia Horti-
culturae, 156:54-62.
Álvarez S & Sánchez-Blanco MJ (2015) Comparison of individual and
combined eects of salinity and decit irrigation on physiological,
nutritional and ornamental aspects of tolerance in Callistemon laevis
plants. Journal of Plant Physiology,185:65-74.
Arévalo JJ, Vélez JES & Intrigliolo DS (2014) Determination of an
ecient irrigation schedule for the cultivation of rose cv. freedom
under greenhouse conditions in Colombia. Agronomía Colombiana,
32:95-102.
Baum C, El-Tohamy W & Gruda N (2015) Increasing the productivity
and product quality of vegetable crops using arbuscular mycorrhizal
fungi: A review. Scientia Horticulturae, 187:131-141.
Box GEP & Cox DR (1964) An analysis of transformations. Journal of
the Royal Statistical Society, 26:211-252.
Chen M, Arato M, Borghi L, Nouri E & Reinhardt D (2018) Benecial
services of arbuscular mycorrhizal fungi – from ecology to applica-
tion. Frontiers in Plant Science, 9:01-14.
Cirillo C, Micco V, Rouphael Y, Balzano A, Caputo R & Pascale S
(2017) Morpho-anatomical and physiological traits of two Bougain-
villea genotypes trained to two shapes under decit irrigation. Trees
- Structure and Function, 31:173-187.
Elansary HO, Skalicka-Wozniak K & King IW (2016) Enhancing stress
growth traits as well as phytochemical and antioxidant contents of
Spiraea and Pittosporum under seaweed extract treatments. Plant
Physiology and Biochemistry, 105:310-320.
Ghini R (2004) Coletor solar para desinfestação de substratos para
produção de mudas sadias. Jaguariúna, Embrapa Meio Ambiente. 5p.
(Circular Técnica, 4).
Giovanetti M & Mosse B (1980) An evaluation of techniques for
measuring vesicular arbuscular mycorrhizal infection in roots. New
Phytologist, 84:489-500.
Gómez-Bellot MJ, Ortuño MF, Nortes PA, Vicente-Sánchez J, Bañón
S & Sánchez-Blanco MJ (2015) Mycorrhizal euonymus plants and
reclaimed water: biomass, water status and nutritional responses.
Scientia Horticulturae, 186:61-69.
Gonçalves J, Borges Júnior JCF, Carlos LA, Silva APCM & Souza
FA (2019a) Bioactive compounds in edible owers of garden pansy
in response to irrigation and mycorrhizal inoculation. Revista Ceres,
66:407-415.
Gonçalves J, Silva GCO & Carlos LA (2019b) Compostos bioativos em
ores comestíveis. Perspectivas Online: Biológicas & Saúde, 9:11-20.
Heitor LC, Freitas MSM, Brito VN, Carvalho AJC & Martins MA (2016)
Crescimento e produção de capítulos orais de calêndula em resposta
à inoculação micorrízica e fósforo. Horticultura Brasileira, 34:26-30.
Janarny G, Gunathilake KDPP & Ranaweera KKDS (2021) Nutraceu-
tical potential of dietary phytochemicals in edible owers - A review.
Journal of Food Biochemistry, 45:e13642.
Janowska B, Rybus-Zajac M, Horojdko M, Andrzejak R & Siejak D
(2016) The eect of mycorrhization on the growth, owering, content
of chloroplast pigments, saccharides and protein in the leaves of Sin-
ningia speciosa (Lodd.) Hiern. Acta Agrophysica, 23:213-223.
Janowska B & Andrzejak R (2017) Eect of mycorrhizal inoculation
on development and owering of Tagetes patula l. “yellow boy” and
Salvia splendens buc’hoz ex etl. “saluti red.” Acta Agrobotonica,
70:06-11.
Kheyri Z, Moghaddam M & Farhadi N (2022) Inoculation eciency of
dierent mycorrhizal species on growth, nutrient uptake, and antiox-
idant capacity of calendula ocinalis l.: a comparative study. Journal
of Soil Science and Plant Nutrition, 22:1160-1172.
Kinupp VF & Lorenzi H (2014) Plantas alimentícias não convencionais
(PANC) no Brasil. Guia de identicação, aspectos nutricionais e re-
ceitas ilustradas. São Paulo, Instituto Plantarum de Estudos de Flora.
768p.
Kokkoris V, Hamel C & Hart MM (2019) Mycorrhizal response in crop
versus wild plants. PLoS One, 14:01-16.
Lopes NF & Lima MGS (2015) Fisiologia da produção. Viçosa, Editora
UFV. 492p.
Majewska ML, Rola K & Zubek S (2017) The growth and phosphorus
acquisition of invasive plants Rudbeckia laciniata and Solidago
gigantea are enhanced by arbuscular mycorrhizal fungi. Mycorrhiza,
27:83-94.
Moreira FMS & Siqueira JO (2006) Microbiologia e bioquímica do solo.
2a ed atual. e ampl. Lavras, Editora UFLA. 729p.
Pavithra D & Yapa N (2018) Arbuscular mycorrhizal fungi inoculation
enhances drought stress tolerance of plants. Groundwater for Sustain-
able Development, 7:490-494.
Püschel D, Rydlová J & Vosátka M (2014) Can mycorrhizal inoculation
stimulate the growth and owering of peat-grown ornamental plants
under standard or reduced watering?. Applied Soil Ecology, 80:93-99.
R Development Core Team (2021) R: A language and environment for
statistical computing. Available at: <https://www.R-project.org/>.
Accessed on: September 13th, 2021.
Reis C, Queiroz F & Fróes M (2004) Jardins Comestíveis. São Paulo,
IPEMA. 18p.
Ristvey AG, Lea-Cox JD & Ross DS (2007) Nitrogen and phosphorus
uptake eciency and partitioning of container-grown azalea during
spring growth. Journal of the American Society for Horticultural
Science, 132:563-571.
Rivas-García L, Navarro-Hortal MD, Romero-Márquez JM, Forbes-Her-
nandez TY, Valera-López A, Llopis J, Sánchez-González C & Quiles
JL (2021) Edible owers as a health promoter: An evidence-based
review. Trends in Food Science & Technology, 117:46-59.
Rydlová J, Sykorová Z, Slavíková R & Turis P (2015) The importance
of arbuscular mycorrhiza for Cyclamen purpurascens subsp. immacu-
latum endemic in Slovakia. Mycorrhiza, 25:599-609.
Saini I, Aggarwal A & Kaushik P (2019) Inoculation with mycorrhizal
fungi and other microbes to improve the morpho-physiological and
oral traits of Gazania rigens (L.) Gaertn. Agriculture, 9:51.
Santos IC & Reis SN (2021) Edible owers: traditional and current use.
Ornamental Horticulture, 27:438-445.
Smith SE & Read DJ (2008) Mycorrhizal symbiosis. 3ª ed. Amsterdam,
Elsevier. 800p.
Sun TZ, Fan L, Mu HN & Witherspoon A (2021) Arbuscular mycorrhizal
fungus and its positive eects on ornamental plants. In: Wu QS, Zou
YN & Xu YJ (Eds.) Endophytic Fungi: Biodiversity, Antimicrobial
Activity and Ecological Implications, Series Microbiology Research
Advances. New York, Nova Science Publishers. p.79-100.
Taiz L & Zeiger E (2013) Fisiologia vegetal. 5ª ed. Porto Alegre,
Artmed. 918p.
Ugolini F, Bussotti F, Raschi A, Tognetti R & Ennos AR (2015) Phys-
iological performance and biomass production of two ornamental
shrub species under decit irrigation. Trees - Structure and Function,
29:407-422.
Wu L, Liu J, Huang W, Wang Y, Chen Q & Lu B (2022) Exploration of
Osmanthus fragrans Lour.’s composition, nutraceutical functions and
applications. Food Chemistry, 377:131853.
Xu L, Li T, Wu Z, Feng H, Yu M, Zhang X & Chen B (2018) Arbuscular
mycorrhiza enhances drought tolerance of tomato plants by regulating
the 14-3-3 genes in the ABA signaling pathway. Applied Soil Ecology,
125:213-221.
Zhang S, Lehmann A, Zheng W, You Z & Rillig MC (2019) Arbuscular
mycorrhizal fungi increase grain yields: a meta-analysis. New Phytol,
222:543-555.
Zubek S, Rola K, Szewczyk A, Majewska ML & Turnau K (2015)
Enhanced concentrations of elements and secondary metabolites in
Viola tricolor l. induced by arbuscular mycorrhizal fungi. Plant and
Soil, 390:129-142.
