Arbuscular mycorrhizal fungi, phosphorus and organic residues in Peltophorum dubium (Spreng.) Taub. seedlings

Fungos micorrízicos arbusculares, fósforo e resíduos orgânicos em mudas de Peltophorum dubium (Spreng.) Taub.

Abstract

Studies have underscored a growingdemand for innovative practices in the cultivation of seedlings from forest species, with a notable emphasis on the utilization of organic waste, inoculation with arbuscular mycorrhizal fungi (AMF), and phosphate fertilization. This study aimed to evaluate the impact of organic residues, inoculation with AMF, and phosphorus on the growth and quality of Peltophorum dubium (Spreng.) Taub. seedlings. Two independent experiments were conducted. In Experiment I, treatments included inoculation with various AMF species: control (without inoculation), Clareoideoglomus etunicatum, Rhizophagus heterosporum, Rhizophagus clarum, and MIX (a combination of the three AMF species), all in conjunction with varying doses of phosphorus (0, 60, 120, 180, and 240 mg kg^-1 soil). In Experiment II, treatments comprised a control group (without AMF) and inoculation with Glomus clarum, Gigaspora margarita, Gigaspora albida, Clareoideoglomus etunicatum, and MIX (a combination of the four AMF species), each associated with four substrates: S1) soil + coarse sand – SCS, S2) SCS + poultry manure, S3) SCS + cattle manure, and S4) SCS + sheep manure. Peltophorum dubium seedlings exhibited heightened growth with the inoculation of R. heterosporum, R. clarum, and MIX. Positive responses were observed in seedlings when exposed to organic residues, particularly sheep manure, resulting in increased biomass production and enhanced Dickson quality index. The AMF inoculation, specifically with R. heterosporum, R. clarum, and MIX, provided optimal growth conditions for P. dubium seedlings. Remarkably, the utilization of organic residues, notably substrates with chicken manure and cattle manure, exerted substantial positive effects on both growth and quality of P. dubium seedlings.

Keywords:
alternative substrates; ‘canafístula’; Fabaceae; poultry manure; symbiosis

Resumo

Os trabalhos têm mostrado demanda crescente na busca de práticas para produção de mudas de espécies florestais, destacando tendências no aproveitamento de resíduos orgânicos, inoculação com fungos micorrízicos arbusculares (FMA) e adubação fosfatada. Objetivou-se por meio deste estudo avaliar o efeito de resíduos orgânicos, inoculação com fungos micorrízicos arbusculares (FMA) e fósforo no crescimento e qualidade de mudas de Peltophorum dubium (Spreng.) Taub. Dois experimentos foram realizados independentes. Para o Experimento I, os tratamentos consistiram na inoculação com as espécies de FMA: controle (sem-inoculado), Clareoideoglomus etunicatum, Rhizophagus heterosporum, Rhizophagus clarum e MIX (mistura das três espécies de FMA), todos associados a doses de fósforo (0, 60, 120, 180 e 240 mg kg^-1 de solo). Para experimento II, os tratamentos consistiram em uma testemunha (sem FMA) e inoculação com Glomus clarum, Gigaspora margarita, Gigaspora albida, Clareoideoglomus etunicatum e MIX (mistura das quatro espécies de FMA), associados a quatro substrato: S1) solo + areia grossa – SCS, S2) SCS + esterco de aves, S3) SCS + esterco bovino e S4) ECS + esterco ovino. Mudas de P. dubium apresentaram maior crescimento com a inoculação de R. heterosporum, R. clarum e MIX. As mudas responderam positivamente ao uso de resíduos orgânicos, principalmente esterco ovino, aumentando a produção de biomassa e o índice de qualidade de Dickson. Mudas de P. dubium se beneficiaram da inoculação com FMA, sendo que os inóculos R. heterosporum, R. clarum e MIX proporcionaram as melhores condições de crescimento. Mudas de P. dubium responderam expressivamente no crescimento e qualidade ao uso de resíduos orgânicos, principalmente ao esterco de galinha e bovino.

Palavras-chave:
substratos alternativos; canafístula; Fabaceae; cama de frango; simbiose

1. Introduction

Seedling production plays a pivotal role in determining forest quality, serving objectives that span commercial exploitation and conservation initiatives. Generally, areas designated for cultivating forest species often exhibit low fertility and suboptimal soil management practices, thereby compromising the productive potential inherent in these species. Araujo et al. (2018) underscore the necessity for studies aimed at producing high-quality seedlings and reducing costs, particularly in response to the escalating demand for environmental projects involving native species to rehabilitate degraded areas.

Among the myriad promising practices associated with the production of seedlings for forest species, noteworthy trends include the utilization of organic residues, inoculation with arbuscular mycorrhizal fungi (AMF), and phosphate fertilization. Arbuscular mycorrhizal fungi (AMF) present a viable alternative for seedling production, enhancing plant capacity to absorb water and nutrients from the soil (Silva et al., 2022; Nardi et al., 2023). Additionally, when coupled with the host species, they augment the root surface area, thereby fostering heightened metabolism and overall plant growth (Pereira et al., 2022; Nardi et al., 2022).

Within mycorrhizal associations, one of the primary soil nutrients absorbed by AMF is phosphorus (Lima et al., 2020), a vital element for metabolism and growth but often limited in availability to plants due to its fixation in soils of tropical regions (Pereira et al., 2021). However, research on the association between AMF and phosphorus remains inadequate for P. dubium seedlings. Studies have been undertaken to elucidate the dependency of AMF inoculation for various tree species, particularly in the context of seedling formation (Silva et al., 2017).

Another sustainable practice in nursery management involves incorporating organic residues for formulating substrates. When introduced, these residues contribute to physicochemical attributes of the soil, thereby favoring plant nutrition and growth (Araújo et al., 2018; Santos et al., 2020a). The choice of substrate is critical for the growth and quality of seedlings in the nursery (Santos et al., 2020b). However, the literature lacks registered information on the association of AMF with substrates based on organic materials for P. dubium seedlings.

We hypothesize that the use of bioinputs, represented here by AMF, associated with phosphate fertilization or organic residues, can augment the initial growth and quality of P. dubium seedlings. Consequently, our objective is to evaluate the effect of AMF associated with organic residues and varied phosphorus doses on the growth of P. dubium seedlings.

2. Material and Methods

2.1. Seeds collection, seedlings formation and general conditions

The species employed in this experiment was Peltophorum dubium, and seeds were gathered from various matrices in the municipality of Dourados, State of Mato Grosso do Sul. Seed dormancy was overcome by immersing the seeds in hot water at 80 °C for 24 hours (Davide and Silva, 2008). Subsequently, the seeds were sown in polyethylene tubes (120 cm³ capacity) filled with a commercial substrate (Bioplant^®) and remained in these tubes until the transplanting date, 50 days after sowing. No fertilization was applied to the seedlings during this initial period.

The experiments were conducted in the seedling nursery of the Faculty of Agrarian Sciences, Federal University of Grande Dourados (22°11’53.2” S; 54°56’02.3” W), located in the municipality of Dourados, Mato Grosso do Sul. The nursery was covered with a 150-micron-thick transparent low-density polyethylene film, with a black nylon screen on the sides providing 70% shading. Experiment I took place from July to December 2020, while Experiment II occurred from June to November 2019.

2.2. Experiment I – AMF and P in P. dubium seedlings

The experimental design was completely randomized, and treatments involving AMF and P (phosphorus) were combined in a factorial arrangement. Five levels of AMF and five levels of P fertilizer were applied, each with four replicates. Each experimental unit consisted of one pot containing two plants. The mycorrhizal treatments included inoculation with AMF species (control, Clareoideoglomus etunicatum, Rhizophagus heterosporum, Rhizophagus clarum, and MIX - a combination of the three AMF species). The AMF strains (registration number: A27569B) were obtained from Embrapa Maize and Sorghum. Phosphorus was applied at doses of 0, 60, 120, 180, and 240 mg P kg^-1 of soil, using KH₂PO₄ as the phosphorus source.

The substrate for this experiment was Oxisols (USDA classification), corresponding to Dystrophic Red Latosol (Brazilian classification) (Santos et al., 2018), with the following initial chemical attributes (before correction): pH H₂O = 5.2, P (Melich-1) = 17.6 mg/dm³, S-SO₄ = 14.70 mg/dm³, K = 0.60 cmol_c dm³, Ca = 3.58 cmol_c dm³, Mg = 1.38 cmol_c dm³, Al = 0.17 cmol_c dm³, H + Al = 6.41 cmol_c dm³, Organic matter = 22.24 g/dm³, organic carbon = 12.90 g/dm³, sum of bases = 5.56 cmol_c dm³, CEC = 11.97 cmol_c dm³, V (%) = 46.45, m (%) = 2.97, B = 0.41 mg/dm³, Cu = 14.60 mg/dm³, Fe = 47.10 mg/dm³, Mn = 77.00 mg/dm³, and Zn = 2.80 mg/dm³, and a mixture with coarse sand in a 2:1 (v/v) ratio. Soil correction and fertilization were performed by applying one gram of soil for each dm³ of limestone per cubic meter of soil. To ensure the presence of only mycorrhizal fungi after inoculation, the substrate was autoclaved at 121º C and 1 atm pressure for one hour and later placed in plastic pots (7 dm³ capacity).

2.3. Experiment II – AMF and organic residues in P. dubium seedlings

The experimental design was completely randomized, in a 6 x 4 factorial arrangement, with four replicates, and one pot containing two plants per experimental unit. Treatments included a control group (without AMF) and inoculation with AMF species Rhizaphagus clarum, Gigaspora margarita, Gigaspora albida, Clareoideoglomus etunicatum, and MIX (a combination of the four AMF species). These treatments were combined with four substrates containing organic residues: S1) (soil + coarse sand – SCS) in a 2:1 (v/v) ratio, S2) SCS + poultry manure, S3) SCS + cattle manure, and S4) SCS + sheep manure, all in a proportion of 2:1:1 (v/v). The soil used in this experiment was classified as Oxisols (USDA), corresponding to Dystrophic Red Latosol (Santos et al., 2018), with the same chemical attributes as in Experiment I.

Soil correction and fertilization were conducted by applying one gram of soil for each dm³ of limestone and 700 g of phosphorus for each m³ of soil, in the form of organic residues. The quantities used were 68.93 g/dm³ poultry manure, 68.63 g/dm³ cattle manure, and 72.95 g/dm³ sheep manure, corrected for 60% availability in the first year. Substrates were packed into 0.08-micron-thick autoclave bags (20 L capacity) made of high-density polyethylene and sterilized in an autoclave at 121º C and 1 atm pressure for one hour. Subsequently, these bags were placed in plastic pots (7 dm³ capacity).

2.4. Inoculation of AMF in the substrates

The inoculation of arbuscular mycorrhizal fungi (AMF) took place at the seedlings' transplanting date. AMF inoculum, comprising a mixture of soil, spores, and roots colonized with AMF, was applied by adding 50 cm³ of inoculum in proximity to the root system of seedlings (approximately 3 cm from the roots and hyphae). The control treatment did not receive any inoculation. The AMF isolates, Clareoideoglomus etunicatum (donated by the Laboratory of Organic Matter and Soil Microbiology at the State University of Mato Grosso do Sul), Rhizophagus heterosporum, and Rhizophagus clarum (registration number: A27569B, obtained from Embrapa Maize and Sorghum), were multiplied in a substrate composed of a 1:1 (v/v) mixture of soil and coarse sand. The substrate was sterilized in an autoclave at 121 °C and 1 atm pressure for 1 hour before being placed in plastic trays with a capacity of 20 dm³. A layer of soil containing AMF propagules was then applied over the sterile substrate, with Brachiaria ruziziensis as the host plant. After 150 days, when the host plants were dehydrated and died, the substrates were stored in plastic bags and later used as a source of inoculum for AMF.

2.5. Assessments

In both experiments, the following characteristics were evaluated at 30, 60, 90, 120, and 150 days after transplanting (DAT): plant height (PH) measured with a graduated ruler (cm), stem diameter (SD) measured with a digital caliper (mm), and height: diameter ratio (HDR) calculated. At 150 DAT, seedlings were removed from the pots, and shoots (leaves + stem) and roots were separated to determine dry mass. Shoot and root fresh mass (SFM and RFM) were weighed using a precision analytical balance (0.001 g). The collected material was then dried in a forced air circulation oven at 60° ± 5 for 72 hours to obtain shoot dry matter (SDM) and root dry matter (RDM). SDM and RDM were summed to obtain the total dry matter (TDM). The shoot: root ratio (SRR) was calculated as SRR = (SDM/RDM), and Dickson’s quality index (DQI) was calculated using the formula: DQI = TDM/ (HDR + SRR) (Dickson et al., 1960). Mycorrhizal dependence (MD) and mycorrhizal efficiency (ME) were obtained from the data of dry matter of mycorrhizal seedlings (DMM) and dry matter of non-mycorrhizal seedlings (DMN) using the formulas: MD (%) = ((DMM – DMN) / DMM) x 100 and ME (%) = ((DMM – DMN) / DMN) x 100, proposed by Plenchette et al. (1983).

2.6. Data analysis

For Experiment I, all data underwent ANOVA (F test, p < 0.05). When significant, means were compared using the Tukey’s test (p ≤ 0.05). Pearson’s correlation analysis and cluster analysis were performed at p ≤ 0.05. Statistical analyses were conducted in the R software R core team 2019 (Pinheiro et al., 2020) using generalized linear mixed models (GLMM), and means were obtained by Tukey’s test at a 5% probability, using the R software.

For Experiment II, all data underwent ANOVA (F test, p < 0.05), and means were compared using the by Tukey’s test at a 5% (p ≤ 0.05). In both experiments, data for periods of evaluation were subjected to linear, quadratic, or exponential regression analyses. Statistical analyses were conducted in the R software (Pinheiro et al., 2020).

3. Results and Discussion

3.1. Experiment I – AMF and P in P. dubium seedlings

The biometric characteristics were evaluated based on the isolated effects of arbuscular mycorrhizal fungi (AMF) and phosphorus (P). This trend aligns with the findings of Bassan et al. (2018), who similarly did not observe an interaction between P doses and mycorrhizal fungi on the growth of P. dubium seedlings (p<0.05), indicating only isolated effects. Conversely, different results were obtained in the development of Schizolobium amazonicum seedlings concerning P doses associated with AMF species, with Brito et al. (2017) observing a positive interaction between these factors.

It is noteworthy that varying results may emerge when evaluating seedling production of native species in association with different AMF, given that the benefits derived from symbiosis depend on the intricate interaction between microorganisms and hosts, as well as prevailing environmental conditions (Carvalho et al., 2022). Plant responses to inoculation are contingent upon the physiological and biochemical compatibility between the plants and AMF, which is intricately linked to the inherent behavior of each species (Frey, 2019).

Analyzing the isolated effects of P doses without AMF inoculation, a significant impact was observed for stem diameter (SD) and height/diameter ratio (HDR), although not for plant height (PH). Conversely, in the absence of phosphate doses but with AMF inoculation, a significant effect was observed for PH and SD. Significant interactions between AMF species and evaluation periods were noted for PH, SD, and HDR, as well as significant interactions between P doses and evaluation periods for SD and HDR. However, no interaction was observed for PH, indicating that phosphate fertilization did not influence height increases in P. dubium seedlings.

Exploring the relationship between different AMF at each evaluation period (30, 60, 90, 120, and 150 DAT) with PH revealed no significant differences between treatments at 30 and 60 DAT. Yet, at 90, 120, and 150 DAT, a significant difference emerged, with the control (without inoculum), R. clarum, and MIX yielding superior performance in terms of plant height. In contrast, seedlings inoculated with R. heterosporum and C. etunicatum exhibited the lowest plant height, with C. etunicatum displaying the poorest performance (Figure 1A).

Figure 1
AMF within each evaluation period for the characteristics height (A) and stem diameter (B) in Peltophorum dubium seedlings. Means followed by the same letter do not differ statistically from each other by Tukey test (p > 0.05).

Examining the variable SD, no significant difference was observed at 30 DAT between treatments (Figure 1B). At 60 DAT, however, a significant difference emerged between the control treatment (without inoculum), R. clarum, and MIX compared to treatments with R. heterosporum and C. etunicatum.

The height of P. dubium seedlings was influenced by different AMF and evaluation periods. A linear trend was observed, with the control, MIX, and R. clarum exhibiting the highest average growth at 150 DAT (Table 1). Seedling height is a crucial parameter for the classification, selection, and commercialization of forest species (Baldin et al., 2015). All seedlings, with heights ranging from 24.65 cm to 43 cm at the end of 150 DAT, were deemed suitable for field use, falling within the optimal range of 15 to 30 cm (Paiva and Gomes, 2000).

Table 1
Equation of Height of Peltophorum dubium seedlings at different evaluation periods as a function of different AMF´s.

Planta height (cm)
AMF	Equation	R2
AMF: C. etunicatum	Y= 6.7+0.122x	0.99
AMF: MIX	Y=3.86+0.25x	0.95
AMF: R. clarus	Y=4.56+0.243x	0.95
AMF: R. heteros	Y=6.15+0.192x	0.92
Without AMF	Y=4.54+0.272x	0.94

Stem diameter was also influenced by AMF inoculation across evaluation periods, demonstrating a linear response. Treatments using R. clarum, without inoculation, MIX, and R. heterosporum exhibited a larger mean diameter at 150 DAT (Table 2). A larger stem diameter is indicative of a seedling's enhanced chances of survival in the field after planting Andivia et al., (2021).

Table 2
Equation of evaluation periods as a function of each AMF (A) and dose of P (B) for the characteristic stem diameter (SD) in Peltophorum dubium seedlings.

Stem diameter (mm)
A
AMF	Equation	R2
AMF: C. etunicatum	Y= 1.8+0.0225x	0.97
AMF: MIX	Y=0.462+0.662x	0.99
AMF: R. clarus	Y=0.25+0.0777x	0.98
AMF: R. heteros	Y=0.651+0.0512x	0.98
Without AMF	Y=0.842+0.0662x	0.97
B
P doses	Equation	R2
0	Y= 0.668+0.0585x	0.99
60	Y=0.48+0.0655x	0.98
120	Y=0.575+0.0589x	0.99
180	Y=0.641+0.0587x	0.98
240	Y=1.14+0.0423x	1

Comparing evaluation periods for each P dose revealed a significant effect of the doses for SD, represented by a linear function. The dose of 60 mg kg^-1 performed better at all evaluation periods compared to other treatments, highlighting the highest values at 30 and 150 DAT. Conversely, the highest dose of 240 mg kg^-1 presented the lowest values of SD. This suggests that P. dubium seedlings, in the absence of phosphate fertilization, exhibited superior development for SD compared to the dose of 240 mg kg^-1, indicating the detrimental effects of this high dose on seedling development.

Phosphorus, integral to various metabolic processes, influenced the development of P. dubium seedlings. Lower P doses promoted superior plant development, while higher doses exhibited a deleterious effect. Phosphorus plays an important role in photochemical activities, enhancing growth through increased ATP production, thereby contributing to biomass production.

Seedling height and stem diameter, vital morphological parameters, are indispensable for analyzing the quality of forest seedlings. However, these factors should not be assessed in isolation to accurately evaluate seedling quality (Gonçalves et al., 2013).

Correlation analysis results revealed positive and significant correlations between the variables studied, except for the correlation between SRR and RFM and RDM, which, although positively correlated, were not statistically significant (Figure 2). The variable HDR exhibited a negative correlation with the other variables and is used as a characteristic to evaluate seedling quality. The highest HDR observed was 7.0 in the treatment with 120 mg kg^-1 using R. heterosporum.

Figure 2
Pearson's correlation for quantitative and qualitative characteristics in Peltophorum dubium seedlings inoculated with AMF and under different doses of P.

The highest positive correlations were observed between SDM and SFM and between TDM and SFM (0.99 and 0.97, respectively). This positive correlation between dry matter (RDM and SDM) and seedling quality (DQI) indicates that biomass production of Peltophorum dubium seedlings is directly related to their quality. Plants inoculated with C. etunicatum were grouped in the lower left quadrant of principal component analysis, suggesting that C. etunicatum exhibited similar behavior across different P doses compared to the other AMF species, with HDR influencing this behavior (Figure 3A).

Figure 3
Principal component analysis (A) and cluster analysis (B) in Peltophorum dubium seedlings inoculated with AMF and under different doses of P.

The correlation was exceptionally high for the evaluated characteristics, with the first component (Axis 1) explaining 78.2% of data variability, while the second component (Axis 2) explained 11.3%. The negative correlation of HDR with other characteristics was evident. The dendrogram from multivariate analysis divided the treatments into three groups, with treatments involving C. etunicatum for all doses forming a large cluster, indicating similarity and greater dissimilarity compared to other treatments (Figure 3B).

Inoculation with AMF significantly enhanced the growth variables analyzed, although this effect was not observed for AMF C. etunicatum, which yielded lower growth values in the present experimental conditions. The benefits of symbiosis extend beyond mere growth, encompassing nutritional enhancements, improved root system utilization and conservation, heightened tolerance to biotic or abiotic stresses, and physiological and biochemical changes (Pereira et al., 2022), such as increased photosynthetic rates and root production.

3.2. Experiment II - AMF and organic residues in P. dubium seedlings

The inoculation of mycorrhizal fungi and the incorporation of organic residues into substrate formulations to produce P. dubium seedlings elicited distinct effects. Noteworthy interactions were observed between AMF and the evaluation period for stem diameter, as well as between substrate composition and the evaluation period for plant height, stem diameter, and height/diameter ratio (HDR).

P. dubium seedlings cultivated in substrates enriched with organic residues exhibited enhanced growth compared to those without such additions, signifying that the inclusion of organic residues positively contributed to increased growth characteristics. This effect was particularly prominent at 120 and 150 days after transplanting (DAT), with seedlings grown in substrate amended with sheep manure displaying the most substantial growth (50.86 cm) compared to those in the substrate lacking organic residues, which achieved values of 23.18 cm at 150 DAT (Table 3).

Table 3
Height, stem diameter, and height: diameter ratio (HDR) of Peltophorum dubium seedlings grown in different substrates in function of evaluation periods.

Plant Height (cm)
Substrates	30 DAT	60 DAT	90 DAT	120 DAT	150 DAT
S1	7.32 a	12.60 a	15.07 c	19.88 b	23.18 b
S2	6.85 a	11.30 a	18.26 bc	35.42 a	46.43 a
S3	6.80 a	11.79 a	19.86 b	34.60 a	48.43 a
S4	7.29 a	13.91 a	26.20 a	43.12 a	50.86 a
Stem diameter (mm)
Substrates	30 DAT	60 DAT	90 DAT	120 DAT	150 DAT
S1	1.92 a	3.17 a	4.15 a	4.78 b	5.03 b
S2	1.71 a	2.56 b	4.25 a	7.40 a	9.18 a
S3	1.76 a	2.66 b	4.25 a	7.06 a	9.42 a
S4	1.83 a	2.84 ab	4.67 a	7.05 a	8.85 a
Height-diameter ratio (HDR)
Substrates	30 DAT	60 DAT	90 DAT	120 DAT	150 DAT
S1	4.15 a	4.26 a	3.94 c	4.44 c	4.90 c
S2	4.34 a	4.74 a	4.57 bc	5.17 b	5.63 bc
S3	4.23 a	4.69 a	4.86 b	5.32 b	5.63 bc
S4	4.32 a	5.24 a	5.96 a	6.46 a	6.09 a

• Means followed by the same letter do not differ from each other by the Tukey test (p < 0.05). S1) Soil + sand – SCS, S2) SCS + chicken manure, S3) SCS + cattle manure, and S4) SCS + sheep manure.

Stem diameter of P. dubium seedlings was significantly influenced by the interaction between substrates containing organic residues and evaluation period (Table 3). The diameter exhibited substantial increases from 60 days after transplanting onward. Seedlings grown in substrate with cattle manure presented the highest diameter (9.42 cm), a statistically superior result compared to seedlings grown without organic residues, which displayed a diameter of 5.03 cm (Table 3). Padilha et al. (2018) reported similar findings when assessing the growth of P. dubium seedlings in commercial and organic substrates.

The HDR of P. dubium seedlings showed no differences until 60 days after transplanting (Table 3). Subsequently, an increase in HDR was observed from 60 to 150 DAT for seedlings grown in substrate with sheep manure. According to Araujo et al. (2020), HDR is linked to seedling endurance, with low values indicating more tender or lignified plants that possess a greater chance of survival after field transplanting. Accordingly, seedlings produced in substrates S1, S2, and S3 exhibited optimal characteristics. Generalized mixed models generated estimation equations for plant height (PH), stem diameter (SD), and HDR, providing a foundation for future studies with P. dubium under similar conditions aiming to predict measurements of these variables from 0 to 150 DAT (Table 4).

Table 4
Equations of height, diameter, and height:diameter (HDR) of Peltophorum dubium seedlings in different substrate at different evaluation periods.

Substrates	Height plant	Stem diameter	HDR
S1	e(1.721 +0.009 t)	e(1.008 +0.008 t)	e(1.427 -0.003 t)
S2	e(1.328 +0.016 t)	e(1.015 +0.014 t)	e(1.301+0.001 t)
S3	e(1.335 +0.016 t)	e(1.014 +0.014 t)	e(1.269+0.002 t)
S4	e(1.407 +0.017 t)	e(1.014 +0.016 t)	3(1.073 +0.010 t)

• S1: Soil + sand – SCS; S2: SCS + chicken manure; S3: SCS + cattle manure; S4: SCS + sheep manure. e (exponential).

AMF species, such as G. albida and C. etunicatum, contributed to an increase in the fresh and dry mass of roots compared to G. clarum and G. margarita, although not differing significantly from the control treatment (Table 5). The inoculation of AMF positively impacted the physiological and nutritional characteristics of the plants, given the vital role these organisms play in nutrient absorption (Wang et al., 2017) and the stimulation of phytohormone synthesis (Pons et al., 2020).

Table 5
Shoot fresh mass (SFM), root fresh mass (RFM), total fresh mass (TFM), shoot dry matter (SDM), root dry matter (RDM), total dry matter (TDM) of Peltophorum dubium seedlings inoculated with AMF. C.E: C. etunicatum, G.A: G. albida, G.C: G. clarum, G.M: G. margarita, and MIX: mixture of C.E + G.A + G.C + G.M in different substrates.

AMF	SFM	RFM	TFM	SDM	RDM	TDS
g plant-1
C. etunicatum	61.87 a	16.49 a	78.36 a	22.79 a	6.28 b	29.07 a
G. albida	69.37 a	19.29 a	88.67 a	27.11 a	8.01 a	35.12 a
G. clarum	61.62 a	10.65 b	72.28 a	22.74 a	4.64 b	27.38 a
G. margarita	50.56 a	10.98 b	61.55 a	19.96 a	4.52 b	24.48 a
MIX	70.62 a	19.00 a	89.63 a	25.83 a	6.75 a	32.58 a
Without AMF	63.12 a	20.60 a	83.73 a	22.98 a	6.44 a	29.42 a

• Means followed by the same letter do not differ from each other by the Scott-Knott test (p < 0.05).

Although there was no significant difference in root dry matter values between seedlings produced without AMF and those inoculated with G. albida, it is noteworthy that G. albida provided 24% higher values compared to the control without AMF. Silva et al. (2018), in their evaluation of Calophyllum brasiliense Cambess. seedlings, reported that AMF inoculation favored increased plant biomass. Lima et al. (2020) similarly found a positive effect of AMF inoculation on seedling performance in Toona ciliata M. Roem, highlighting the importance of AMF inoculation in promoting seedling growth.

In general, seedlings produced with three organic residues exhibited the highest values of shoot fresh and dry mass (Table 6). This indicates that the presence of organic matter is important for biomass production compared to the control, which solely contained soil and sand. Notably, seedlings responded significantly to the application of organic residues, with the highest production of shoot fresh matter recorded at 86.25 g/plant in seedlings grown in sheep manure, a statistically significant difference from seedlings produced in the substrate with only soil and sand.

Table 6
Shoot fresh mass (SFM), root fresh mass (RFM), total fresh mass (TFM), shoot dry matter (SDM), root dry matter (RDM), total dry matter (TDM). of Peltophorum dubium seedlings inoculated with AMF.

Substrates	SFM	RFM	TFM	SDM	RDM	TDM
g plant-1
S1	10.45 b	3.75 c	14.29 b	4.29 b	1.03 c	5.33 b
S2	71.66 a	24.51 a	69.18 a	27.49 a	9.16 a	36.61 a
S3	83.00 a	19.63 b	102.63 a	32.04 a	8.11 a	40.16 a
S4	86.25 a	16.79 b	103.04 a	30.44 a	6.11 a	36.56 a

• Means followed by the same letter do not differ from each other by the Tukey test (p < 0.05). S1: Soil + sand – SCS; S2: SCS + chicken manure; S3: SCS + cattle manure; S4: SCS + sheep manure.

Native and arboreal species typically respond positively to the addition of organic residues to cultivation substrates, especially in soils with low natural fertility, as these materials improve the chemical attributes of the substrate (Santos et al., 2020b; Goelzer et al., 2020). It is worth emphasizing that organic residues can also contribute to the substrate's physical characteristics, such as porosity and density, thereby enhancing water retention and promoting better root system exploration, as observed in Alibertia edulis Rich. (Santos et al., 2023).

In a study by Faria et al. (2016), evaluating the production of Mimosa setosa Benth. seedlings in different substrates based on cattle manure, poultry manure, quail manure, and commercial substrate, the best results for shoot dry mass (SDM), root dry mass (RDM), and total dry mass (TDM) were obtained with a substrate containing 25% commercial substrate + 35% poultry manure and 40% soil. Similarly, Gonzaga et al. (2016), in their evaluation of different substrates and AMF sporulation in Joannesia princeps Vell. LC., Hymenaea courbaril L., and Hevea brasiliense seedlings, reported positive results for SDM, RDM, and TDM with the use of poultry and cattle manure, echoing the findings for P. dubium.

P. dubium seedlings did not exhibit mycorrhizal dependence (Figure 4). Abreu et al. (2018) found mycorrhizal dependence of 25.53% for G. margarita in Enterolobium contortisiliquum seedlings. Symbiotic efficiency was observed for AMFs G. albida and C. etunicatum, with values of 19.64% and 5.5%, respectively (Figure 5). It was observed that C. etunicatum and MIX exhibited minimal symbiotic efficiency, while G. albida displayed the best symbiotic efficiency. In a study by Bassan et al. (2018) involving the inoculation of mycorrhizal fungi and phosphorus doses, P. dubium seedlings exhibited high dependence and mycorrhizal efficiency for the species G. albida and C. etunicatum, while symbiosis with G. clarum and G. margarita was ineffective.

Figure 4
Mycorrhizal dependence in Peltophorum dubium seedlings inoculated with AMF. C.E: C. etunicatum, G.A: G. albida, G.C: G. clarum, G.M: G. margarita, and MIX: mixture of C.E + G.A + G.C + G.M.

Figure 5
Mycorrhizal efficiency in Peltophorum dubium seedlings inoculated with AMF. C.E: C. etunicatum, G.A: G. albida, G.C: G. clarum, G.M: G. margarita, and MIX: mixture of C.E + G.A + G.C + G.M.

The response to AMF inoculation varies with the species and its interactions with the environment, considering edaphoclimatic conditions and the compatibility of the symbiotic organism. In this study, P. dubium seedlings exhibited a more pronounced response to organic residues than to AMF, possibly because these organic materials fulfilled the nutritional needs of the species. Additionally, when organic residues were added to the soil, microbial activity in the substrate increased, potentially leading to lower AMF efficiency. According to Carvalho et al. (2022), mycorrhizal colonization should not be the sole parameter for assessing efficiency, as certain AMF species can be highly infective but inefficient in nutrient provision, failing to enhance plant physiology and growth.

The Dickson’s Quality Index (DQI) of P. dubium seedlings was higher in seedlings produced with poultry and cattle manure (Figure 6). This suggests an improvement in the chemical attributes of the substrate, favoring seedling nutrition and growth. Similar results were reported by Kratka and Correia (2015) when testing different substrates in the production of Myracrodruon urundeuva Allemão seedlings, where optimal results were achieved in substrates with organic residues. The DQI serves as an indicator for evaluating the quality of forest seedlings, considering important parameters such as height, diameter, and biomass through HDR (Medeiros et al., 2018). A higher DQI value correlates with better seedling quality (Melo et al., 2018).

Figure 6
Dickson’s quality index of Peltophorum dubium seedlings in different substrate with organic residues. S1) Soil + sand – SCS, S2) SCS + chicken manure, S3) SCS + cattle manure, and S4) SCS + sheep manure.

The information gleaned from this study may support sustainable practices in commercial nurseries, guiding ex situ cultivation. Future studies should further characterize the nutritional status of P. dubium seedlings under similar conditions, providing additional insights for refining the propagation protocol of this species.

In conclusion, Peltophorum dubium seedlings derived significant benefits from AMF inoculation, with R. heterosporum, R. clarum, and MIX yielding optimal growth conditions. The response of P. dubium seedlings to organic residues was substantial, especially in substrates enriched with chicken manure and cattle manure. While the use of mycorrhizal fungi did not produce a significant effect on P. dubium seedlings, positive symbiotic efficiency was observed for the species C. etunicatum and G. albida.

Acknowledgements

Authors thank CNPq for the first author’s doctoral scholarship (protocol 144972/2019-0).

References

• ABREU, G.M., SCHIAVO, J.A., ABREU, P.M., BOBADILHA, G. and ROSSET, J.S., 2018. Crescimento inicial e absorção de fósforo e nitrogênio de Enterolobium contortisiliquum inoculada com fungos micorrízicos arbusculares. Revista de Ciências Agrárias (Lisboa), vol. 41, no. 1, pp. 156-164. http://dx.doi.org/10.19084/RCA17138
  » http://dx.doi.org/10.19084/RCA17138
• ANDIVIA, E., VILLAR-SALVADOR, P., OLIET, J.A., PUÉRTOLAS, J., DUMROESE, R.K., IVETIC, V., MOLINA-VENEGAS, R., ARELLANO, E.C., LI, G. and OVALLE, J.F., 2021. Climate and species stress resistance modulate the higher survival of large seedlings in forest restorations worldwide. Ecological Applications, vol. 31, no. 6, pp. e02394. http://dx.doi.org/10.1002/eap.2394 PMid:34164882.
  » http://dx.doi.org/10.1002/eap.2394
• ARAÚJO, M., NAVROSKI, M.C. and SCHORN, L.A., 2018. Produção de sementes e mudas: um enfoque à Silvicultura Santa Maria: UFSM, 448 p. http://dx.doi.org/10.32379/9788573913170
  » http://dx.doi.org/10.32379/9788573913170
• ARAÚJO, M.S., CUSTÓDIO, J.P.C., SANTOS, B.F.A., PELÁ, A. and CONEGLIAN, A., 2020. Growth and nutritional efficiency of acacia seedlings in response to phosphate fertilization. Agrária, vol. 15, no. 2, pp. 1-8. http://dx.doi.org/10.5039/agraria.v15i2a7503
  » http://dx.doi.org/10.5039/agraria.v15i2a7503
• BALDIN, T., CONTE, B., DENARDI, L., MORAES, R. and SALDANHA, C.W., 2015. Crescimento de mudas de angico-vermelho em diferentes volumes de substratos. Pesquisa Florestal Brasileira, vol. 35, no. 82, pp. 129-133. http://dx.doi.org/10.4336/2015.pfb.35.82.829
  » http://dx.doi.org/10.4336/2015.pfb.35.82.829
• BASSAN, D.A.Z., SANTOS, S., LOURENTE, E., DAVIDE, L., MEDEIROS, E.D., CARVALHO, L.D. and SOUZA, G., 2018. Mudas de canafístula (Peltophorum dubium (Spreng.) Taub.) com fungos micorrízicos arbusculares. In: C.C. SANTOS and S.P.Q. SCALON, eds. Ecofisiologia e nutrição de espécies frutíferas e arbóreas Nova Xavantina: Pantanal, pp. 126-148.
• BRITO, V.N., TELLECHEA, F.R.F., HEITOR, L.C., FREITAS, M.S.M. and MARTINS, M.A., 2017. Fungos micorrízicos arbusculares e adubação fosfatada na produção de mudas de paricá. Ciência Florestal, vol. 27, no. 2, pp. 485-497. http://dx.doi.org/10.5902/1980509827730
  » http://dx.doi.org/10.5902/1980509827730
• CARVALHO, L.G.V., SANTOS, S.C., LOURENTE, E.R.P., TROVATO, V.W. and SANTOS, C.C., 2022. Jatobazeiro seedlings associated with arbuscular mycorrhizal fungi. Revista Brasileira de Fruticultura, vol. 44, no. 2, pp. e-006. http://dx.doi.org/10.1590/0100-29452022006
  » http://dx.doi.org/10.1590/0100-29452022006
• DAVIDE, A.C. and SILVA, E.A., 2008. Produção de sementes e mudas de espécies florestais Lavras: UFLA, 180 p.
• DICKSON, A., LEAF, A.L. and HOSNER, J.F., 1960. Quality appraisal of white spruce and white pine seedling stock in nurseries. Forestry Chronicle, vol. 36, no. 1, pp. 10-13. http://dx.doi.org/10.5558/tfc36010-1
  » http://dx.doi.org/10.5558/tfc36010-1
• FARIA, J.C.T., CALDEIRA, M.V.W., DELARMELINA, W.M. and ROCHA, R.L.F., 2016. Substratos alternativos na produção de mudas de Mimosa setosa Benth. Ciência Florestal, vol. 26, no. 4, pp. 1075-1086. http://dx.doi.org/10.5902/1980509824996
  » http://dx.doi.org/10.5902/1980509824996
• FREY, S.D., 2019. Mycorrhizal fungi as mediators of soil organic matter dynamics. Annual Review of Ecology, Evolution, and Systematics, vol. 50, no. 1, pp. 237-259. http://dx.doi.org/10.1146/annurev-ecolsys-110617-062331
  » http://dx.doi.org/10.1146/annurev-ecolsys-110617-062331
• GOELZER, A., SILVA, O.B., SANTOS, F.H.M., SANTOS, C.C., HEREDIA ZÁRATE, N.A. and VIEIRA, M.C., 2020. Photosynthetic performance, nutrition and growth of Campomanesia xanthocarpa O. Berg. in chicken manure substrate and liming. Floresta e Ambiente, vol. 22, no. 2, pp. e20200005. http://dx.doi.org/10.1590/2179-8087-floram-2020-0005
  » http://dx.doi.org/10.1590/2179-8087-floram-2020-0005
• GONÇALVES, E.D.O., PAIVA, H.N.D., NEVES, J.C.D.L. and GOMES, J.M., 2013. Nutrição de mudas de Mimosa caesalpiniaefolia Benth. sob diferentes doses de N, P, K, Ca e Mg. Ciência Florestal, vol. 23, no. 2, pp. 273-286. http://dx.doi.org/10.5902/198050989274
  » http://dx.doi.org/10.5902/198050989274
• GONZAGA, L.M., SILVA, S.S., CAMPOS, S.A., FERREIRA, R.P., CAMPOS, A.N.R. and CUNHA, A.C.M.C.M., 2016. Evaluation of substrates and AMF sporulation in the production of seedlings of native forest species. Revista Árvore, vol. 40, no. 2, pp. 245-254. http://dx.doi.org/10.1590/0100-67622016000200007
  » http://dx.doi.org/10.1590/0100-67622016000200007
• KRATKA, P.C. and CORREIA, C.R.M.A., 2015. Crescimento inicial de aroeira do sertão (Myracrodruon urundeuva Allemão) em diferentes substratos. Revista Árvore, vol. 39, no. 3, pp. 551-559. http://dx.doi.org/10.1590/0100-67622015000300016
  » http://dx.doi.org/10.1590/0100-67622015000300016
• LIMA, B.K., RITER NETTO, A.F., MARTINS, M.A. and FREITAS, M.S.M., 2020. Crescimento, acúmulo de nutrientes e fenóis totais de mudas de cedro australiano (Toona ciliata) inoculadas com fungos micorrízicos. Ciência Florestal, vol. 25, no. 4, pp. 853-862. http://dx.doi.org/10.5902/1980509820583
  » http://dx.doi.org/10.5902/1980509820583
• MEDEIROS, M.D.B.C.L., JESUS, H.I., SANTOS, N.F.A., MELO, M.R., SOUZA, V.Q., BORGES, L.S., GUERREIRO, A.C. and FREITAS, L.S., 2018. Índice de qualidade de Dickson e característica morfológica de mudas de pepino, produzidas em diferentes substratos alternativos. Revista Agroecossistemas, vol. 10, no. 1, pp. 159-173. http://dx.doi.org/10.18542/ragros.v10i1.5124
  » http://dx.doi.org/10.18542/ragros.v10i1.5124
• MELO, L.A., ABREU, A.H.M., LELES, P.S.S., OLIVEIRA, R.R. and SILVA, D.T., 2018. Qualidade e crescimento inicial de mudas de Mimosa caesalpiniifolia Benth produzidas em diferentes volumes de recipientes. Ciência Florestal, vol. 28, no. 1, pp. 47-55. http://dx.doi.org/10.5902/1980509831574
  » http://dx.doi.org/10.5902/1980509831574
• NARDI, F.S., CHIOMENTO, J.L.T., COSTA, R.C., TRENTIN, N.S., TRENTIN, T.S., LIMA, G.S. and CALVETE, E.O. 2023. Alterações morfofisiológicas promovidas pela micorriza arbuscular em plantas hortícolas: uma revisão integrativa. In: C.C. SANTOS, ed. Manejo fisiológico e nutricional de plantas: abordagens práticas na agricultura Guarujá: Científica Digital, pp. 79-95. http://dx.doi.org/10.37885/230212152
  » http://dx.doi.org/10.37885/230212152
• NARDI, F.S., CHIOMENTO, J.L.T., TRENTIN, N.S., TRETIN, T.S., BASÍLIO, L.S.P., LIMA, G.P.P. and CALVETE, E.O., 2022. Dinâmica entre fungos micorrízicos arbusculares e fósforo no cultivo do morangueiro em substrato: uma revisão narrativa. Open Science Research VIII, vol. 8, no. 1, pp. 24-38. http://dx.doi.org/10.37885/221110917
  » http://dx.doi.org/10.37885/221110917
• PADILHA, M.S., BARETTA, D.M., SOBRAL, L.S., KRAFT, E. and OGLIARI, A.J., 2018. Crescimento de mudas de canafístula com o uso de adubação biológica e bioestimulante em diferentes substratos. Enciclopédia Biosfera, vol. 15, no. 27, pp. 1-12. http://dx.doi.org/10.18677/EnciBio_2018A32
  » http://dx.doi.org/10.18677/EnciBio_2018A32
• PAIVA, N. and GOMES, M., 2000. Viveiros florestais 2th ed. Viçosa: UFV, 116 p.
• PEREIRA, D.S., COSTA, Y.K.S. and CARVALHO, L.B., 2021. O elemento P: formas e dinâmica em solos tropicais. Revista Agronomia Brasileira, vol. 5, no. 2021. http://dx.doi.org/10.29372/rab202124
  » http://dx.doi.org/10.29372/rab202124
• PEREIRA, S.M.S., JÚNIOR-SAGGIN, O.J., RAMOS, M.L.G. and KONRAD, M.L.F., 2022. A esporulação e colonização radicular por fungos micorrízicos arbusculares em Paepalanthus sp. sob diferentes níveis de umidade em campo rupestre. Uniciências, vol. 26, no. 2, pp. 93-99. http://dx.doi.org/10.17921/1415-5141.2022v26n2p93-99
  » http://dx.doi.org/10.17921/1415-5141.2022v26n2p93-99
• PINHEIRO, J., BATES, D., DEBROY, S., SARKAR, D., 2020. Nlme: linear and nonlinear mixed effects models: R package version v. 3 Vienna: R Foundation for Statistical Computing.
• PLENCHETTE, C., FORTIN, J.A. and FURLAN, V., 1983. Growth responses of several plant species to mycorrhizae in a soil of moderate P-fertility - I. Mycorrhizal dependency under field conditions. Plant and Soil, vol. 70, no. 2, pp. 199-209. http://dx.doi.org/10.1007/BF02374780
  » http://dx.doi.org/10.1007/BF02374780
• PONS, S., FOURNIER, S., CHERVIN, C., BÉCARD, G., ROCHANGE, S., FREY, N.F.D. and PAGÉS, V.P., 2020. Phytohormone production by the arbuscular mycorrhizal fungus Rhizophagus irregularis. PLoS One, vol. 15, no. 10, pp. e0240886. http://dx.doi.org/10.1371/journal.pone.0240886 PMid:33064769.
  » http://dx.doi.org/10.1371/journal.pone.0240886
• SANTOS, C.C., GOELZER, A., SILVA, O.B., SANTOS, F.H.M., SILVERIO, J.M., SCALON, S.P.Q., VIEIRA, M.C. and HEREDIA ZÁRATE, N.A., 2023. Morphophysiology and quality of Alibertia edulis seedlings grown under light contrast and organic residue. Revista Brasileira de Engenharia Agrícola e Ambiental, vol. 27, no. 5, pp. 375-382. http://dx.doi.org/10.1590/1807-1929/agriambi.v27n5p375-382
  » http://dx.doi.org/10.1590/1807-1929/agriambi.v27n5p375-382
• SANTOS, C.C., GUEDES JORGE, H.P., DIAS, L.G.F. and VIEIRA, M.C., 2020b. Shading levels and substrates affect morphophysiological responses and quality of Anadenanthera peregrina (L.) Speg seedlings. Floresta e Ambiente, vol. 27, no. 2, pp. e20190119. http://dx.doi.org/10.1590/2179-8087.011919
  » http://dx.doi.org/10.1590/2179-8087.011919
• SANTOS, C.C., VIEIRA, M.C., HEREDIA ZÁRATE, N.A., CARNEVALI, T.O. and GONÇALVES, W.V., 2020a. Organic residues and bokashi influence in the growth of Alibertia edulis. Floresta e Ambiente, vol. 27, no. 1, pp. e20171034. http://dx.doi.org/10.1590/2179-8087.103417
  » http://dx.doi.org/10.1590/2179-8087.103417
• SANTOS, H.G., JACOMINE, P.K.T., ANJOS, L.H.C., OLIVEIRA, V.A., LUMBRERAS, J.F., COELHO, M.R., ALMEIDA, J.A., ARAÚJO FILHO, J.C., OLIVEIRA, J.B. and CUNHA, T.J.F., 2018. Sistema Brasileiro de Classificação de Solos 5. ed. Rio de Janeiro: Embrapa, 187 p.
• SILVA, C.G.S., SILVA, M.E.C.M., FERREIRA, G.S., SILVA, M.L.R.B., OLIVEIRA, J.P. and SOUZA, R.J.C., 2022. Levantamento bibliográfico sobre a associação de rizóbios e fungos micorrízicos arbusculares em Vigna unguiculata L. Walp. (feijão-caupi). Research. Social Development, vol. 11, no. 13, pp. e297111335412-e297111335412. http://dx.doi.org/10.33448/rsd-v11i13.35412
  » http://dx.doi.org/10.33448/rsd-v11i13.35412
• SILVA, E.N., TAVARES, A.T., SILVA, C.P., FERREIRA, T.A., CARLINE, J.V.G. and NASCIMENTO, I.R., 2018. Fungos micorrízicos arbusculares e doses de fósforo no desenvolvimento de mudas de guanandi. Nativa (Sinop), vol. 6, no. 3, pp. 246-251. http://dx.doi.org/10.31413/nativa.v6i3.4720
  » http://dx.doi.org/10.31413/nativa.v6i3.4720
• SILVA, E.P., FERREIRA, P.A.A., FURTINI-NETO, A.E. and SOARES, C.R.F.S., 2017. Micorrizas arbusculares e fosfato no desenvolvimento de mudas de cedro-australiano. Ciência Florestal, vol. 27, no. 4, pp. 1269-1281. http://dx.doi.org/10.5902/1980509830320
  » http://dx.doi.org/10.5902/1980509830320
• WANG, W., SHI, J., XIE, Q., JIANG, Y., YU, N. and WANG, E., 2017. Nutrient exchange and regulation in arbuscular mycorrhizal symbiosis. Molecular Plant, vol. 10, no. 9, pp. 1147-1158. http://dx.doi.org/10.1016/j.molp.2017.07.012 PMid:28782719.
  » http://dx.doi.org/10.1016/j.molp.2017.07.012

Publication Dates

• Publication in this collection
  18 Mar 2024
• Date of issue
  2024

History

• Received
  01 July 2023
• Accepted
  06 Feb 2024