Use of bovine biofertilizer in cabbage production in alley system

Cabbage cultivation with organic inputs in agroforestry systems may be an alternative for cultivation in the state of Roraima. In this context, the objective of this study was to evaluate the effects of bovine biofertilizer and alley system on the production components of Sooshu hybrid cabbage. The experiment was conducted from August 2019 to July 2020 at the Agrotechnical School of the Federal University of Roraima. The treatments were arranged in randomized blocks, in split plots, with three replicates. The factorial scheme used was 2 × 5, referring to production in systems without and with alleys and five concentrations of bovine biofertilizer (0, 25, 50, 75 and 100% of the 8 L m -2 dose). After 113 days of application of the bovine biofertilizer, the following were evaluated: i) mass of the leaves that form the head; ii) number of outer leaves; iii) mass of outer leaves; iv) transverse and longitudinal diameters and v) yield. The agroforestry system had no influence on cabbage production components. Bovine biofertilizer at concentration of 63.13% promoted higher mass of leaves that form the head and yield of Sooshu hybrid cabbage.


Introduction
Cabbage (Brassica oleracea var. capitata L.) production is an agricultural activity of great importance for Brazil. For this agricultural activity to be economically viable, it needs to be practiced in appropriate times and in places with good edaphoclimatic and market conditions for its commercialization. Cabbage is native to regions of temperate climate, and in the state of Roraima its production is incipient, mainly due to temperature and rainfall intensity during the rainy season. In Roraima, temperatures exceed 32 °C accompanied by radiation levels higher than 25 MJ m -2 day -1 , which can impair the growth, yield and quality of vegetables that require mild temperatures (Castilla & Baeza, 2013). In the agroforestry system, soil cover is one of the most important factors for its protection, so legume species are planted, due to their importance to the biome when the soil is poor and there is indiscriminate use of fire; in addition, they improve the physical, chemical and biological properties of the soil, control weeds and prevent erosion . As a component of the agroforestry system, one of the species used is Gliricidia sepium, for being an arboreal, leguminous and perennial plant, with an average height of 12 to 15 meters and with a diameter of up to 30 cm. This type of management is part of the strategies that can contribute to increasing agricultural production and can be an alternative for cabbage (Brassica oleracea var. capitata) production in the municipality of Boa Vista, Roraima, considering that the system may be able to mitigate the negative effects of the high variability of rainfall and temperature (Santos et al., 2018).
Brassicaceae species, cabbage family, demand high levels of nutrients due to the high conversion rate in a short period of time, so fertilization needs to be supplied frequently and in adequate quantities (Filgueira, 2008). Replacing mineral fertilizers, of high prices, with products of animal origin, available in the field, can be an alternative to improve the chemical, physical and biological attributes of the soil (Pires et al., 2008) and meet the demand of the crop.
Bovine manure fertilizer is a source of bioactive compounds formed by bacteria, yeasts, algae and fungi (Marrocos et al., 2012) and, when applied to the soil, improves its physical (Benbouali et al., 2013), chemical and biological attributes, stimulating plant growth and production (Boraste et al., 2009;Patil, 2010), so it can contribute positively to the nutrition and production of cabbage in a savanna area.
In a study conducted by Silva (2018), evaluating the use of bovine biofertilizer in the cultivation of lettuce (Lactuca sativa L.), foliar application of biofertilizer led to superior results when compared to treatment with conventional fertilization. Saraiva (2020) also observed increments in the production components of common bean (Phaseolus vulgaris) with the application of 125% of bovine biofertilizer.
Considering the relevance of biofertilizers for sustainability, reducing the environmental impacts generated and reducing costs, it is essential to study them as to their real contribution to vegetable yield. Thus, the objective was to evaluate the effects of bovine biofertilizer and alley system on the production of Sooshu hybrid cabbage in the savanna (lavrado) of Roraima, Brazil.

Methodology
The experiment was carried out from August 2019 to July 2020, in the municipality of Boa Vista -RR. According to Köppen's classification, the climate of the municipality is Aw, characterized as Rainy Tropical, hot and humid, with a clear rainy season, after alternating dry and humid periods (Alvares et al., 2013).
In the period of 113 days, daily air temperature ( Figure 1A), rainfall ( Figure 1B) and daily global solar radiation ( Figure   1C) data were recorded at the automatic station of the National Institute of Meteorology (INMET, 2022). The mean temperature was 28.5 °C, with accumulated rainfall of 369.6 mm and solar radiation of 2,575.37 MJ m -2 ( Figure 1). Source: Authors.
The experimental design was in randomized blocks, with split plots, in a 2 × 5 factorial scheme, that is, production systems -without and with alleys, and five huge bovine biofertilizers (0, 25, 50, 75 and 100% of the 8 L m -2 ) all with three The soil of the experimental area of the system without and with alleys was classified as Argissolo Amarelo distrófico (Ultisol) (Embrapa, 2013). The system of alleys with G. sepium trees was implemented in 2013, using cuttings from the Experimental Unit of EMBRAPA-RR in the municipality of Mucajaí, Roraima. In the same year, green manuring was carried out with rattlepod (Crotalaria spp.), dwarf pigeon pea (Cajanus cajan), jack bean (Canavalia ensiformis) and velvet bean (Mucuna pruriens). G. sepium plants were planted at spacing of 7.0 m between rows and 4.0 m between plants of each row. The management of the system consisted in pruning operations and deposition of plant biomass on soil surface. The soil attributes in the system with and without alleys were, respectively: pH = 6.3 and 5.4; P = 18.6 and 3.5 mg dm -3 ; K = 40 and 17 mg dm -3 ; Ca 2+ = 1.12 and 0.52 cmolc dm -3 ; Mg 2+ = 0.35 and 0.13 cmolc dm -3 ; Al 3+ = 0.0 and 0.1 cmolc dm -3 ; H + Al = 0.7 and 0.3 cmolc dm -3 ; base saturation: 69.2 and 69.7%; sulfur = 4.52 and 19.27 mg dm -3 ; and organic matter = 1.21 and 0.94%. The soil of both areas was classified as sandy loam. The analysis of the biofertilizer was not performed, however, the cattle manure used to produce the input had the following attributes: N = 1.94%; P = 0.22%; K = 1.68%; Mg = 0.32%; S = 0.25%; Zn = 78 mg dm-3; Fe = 11344 mg dm -3 ; Mn = 729 mg dm -3 ; Cu = 11 mg dm -3 ; B = 14.2 mg dm -3 ; and organic carbon = 27.14%.
The seedlings of Sooshu hybrid cabbage were prepared in polystyrene trays of 128 cells and were transplanted 21 days after sowing, when they had four true leaves. It was used Tropstrato HA Hortaliças ® , composed of pine bark, peat, expanded vermiculite, enriched with macro and micronutrients. Fertilization was performed according to the results of soil analyses, following the recommendation proposed by Filgueira (2008), applying 200 kg ha -1 of P2O5 and 110 kg ha -1 of K2O, using single superphosphate and potassium chloride as sources of phosphorus and potassium, respectively. Water was supplied by localized drip irrigation with flow rate of 7.5 L h -1 m -1 . During the field activities, irrigation, weed control and alternative phytosanitary control using garlic (Allium sativum) and onion (Allium cepa) extract were performed according to Freitas et al. (2006) at the concentration of 10%.
Bovine biofertilizer was produced according to the recommendation of Diniz et al. (2013). To produce the biofertilizer, equal parts of water and fresh cattle manure were added in a container that does not undergo oxidation, leaving 20% of its volume to be occupied by methane gas produced during fermentation. To release the gas produced by bacteria, one end of a thin hose is Harvest of the usable plots was carried out at 113 days after transplantation, when the heads were compact and well developed. A cut was made at the base of the head and the material was transported to the Laboratory of Technology of Agricultural Products (LTPA) of the Federal University of Roraima, to evaluate the following variables: i) number of outer leaves (leaves plant -1 ); ii) number of inner leaves (leaves plant -1 ); iii) fresh mass of outer leaves (g plant -1 ); iv) fresh mass of leaves that form the head (kg plant -1 ); v) longitudinal diameter (measured from the base to the apex of the head) and vi) transverse diameter, determined with a millimeter ruler; and vii) yield (kg ha -1 ), obtained by estimating the product of the fresh mass of the leaves that form the head by the number of plants per hectare (Silva et al., 2012).
The results were subjected to analysis of variance by the F test; means referring to the system without and with alleys were compared by Tukey test at 5% probability level and means referring to the doses were compared by polynomial regression (Banzatto & Kronka, 2006), using the statistical program Sisvar (Ferreira, 2019).

Results and Discussion
According to the summary of the analysis of variance, it is noted that none of the variables evaluated were influenced by the interaction between the alley system and the application of biofertilizer. The number of leaves outside the head (NOL), the mass of leaves outside the head (MOL) and the number of leaves that make up the head (NLH) were not influenced by any of the sources of variation studied. The longitudinal (DL) and transversal (DT) diameter, the mass of the leaves (MOL) that compose the head and the cabbage productivity (PT) were influenced by the isolated biofertilizer factor (Table 1).  Plants grown in the alley system had NOL of 5.5 leaves plant -1 , while those cultivated in the system without alleys had a higher NOL, on average 3 leaves plant -1 . The numerical superiority of the data in the system without alleys was also observed for the mass of the leaves that form the head, with averages of 130.5 and 167.4 g plant -1 for treatments with and without alley system, respectively ( Table 2). The absence of a significant effect for the number of leaves per plant was also observed by Nomura et al. (2019), when they found that the application of doses of biofertilizer not increased the number of leaves of arugula plants (Eruca vesicaria ssp. sativa). The number of outer leaves is lower than the average value of 9.37 leaves plant -1 recorded by Leão and Alves (2019) when evaluating the yield of cabbage under application of boron sources and doses. Castro (2015), when studying the yield and quality of cabbage fertilized with nitrogen and boron in a protected environment, recorded higher values of mass of outer leaves, Research, Society andDevelopment, v. 11, n. 5, e0511527507, 2022 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v11i5.27507 6 with a maximum of 518.68 g of fresh matter under fertilization with 291.55 kg N ha -1 . The highest means occurred in treatments without alleys (Table 2), influenced by the lower shading compared to the treatments with alleys.
Similar to the number of outer leaves, the production of leaves that form the head was not influenced by the studied sources of variations, with mean values of 24.5 leaves head -1 in treatments with alleys and 30.9 leaves head -1 in treatments without the alley system. The mean values for treatments without and with alley system and 25, 50, 75 and 100% of bovine biofertilizer were 20.7, 23.4, 33.6, 32.9 and 27.9 leaves head -1 , respectively (Table 3). The average number of inner leaves is lower than the average value of 40.9 leaves head -1 recorded by Silva et al. (2012) when studying the yield and development of cabbage cultivars as a function of boron doses. The average NLH of 27.7 does not corroborate the number presented by Silva et al. (2014), who worked with boric acid applications in cabbage at different times and recorded an average of 37.40 leaves head -1 in the treatment with boron application (6.1 kg ha -1 ) at 25 days after transplantation.
The data of longitudinal and transverse diameters of the head were described by a quadratic model as a function of bovine biofertilizer, with maximum values of 12.65 cm and 11.26 cm at concentrations equivalent to 64.70% and 62.93%, respectively (Figure 2 AB). Therefore, it can be observed that the increments in diameters (Figures 2AB) and fresh mass of leaves (Figure 3) caused by the application of the biofertilizer were essential for the increase in yield observed in Figure 4, especially when concentrations around 63% were applied. Castro (2015) observed that the data of transverse diameter of the head were described by quadratic model as a function of nitrogen doses, with a maximum value of 15.33 cm with the dose equivalent to 265 kg of N ha -1 . The beneficial effect of bovine biofertilizer was also reported by Lima et al. (2018)   The results obtained agree with those found by Guerra et al. (2013), who reported that organic fertilization can totally replace mineral fertilization, and this practice should be recommended. The positive increment in the agronomic characteristics of cabbage may be related to the rapid availability of nutrients by the biofertilizer, which provides the essential elements for plants and contributes to the improvement of soil attributes.
There was no significant effect of the interaction between biofertilizer concentrations and alley systems for fresh mass of leaves that form the cabbage head, however, there was a significant effect for the biofertilizer factor individually. The application of increasing doses of the input increased the mass of leaves that form the head of cabbage plants up to the maximum estimated concentration of 63.15%, with a maximum head mass of 548.4 g plant -1 (Figure 3). The beneficial effects of biofertilizer application on the growth of cabbage plants is related to its nutritional composition, which when applied to soil, improves its physical (Benbouali et al., 2013), chemical and biological properties, stimulating plant growth and production (Patil, 2010). Source: Authors.
The application of bovine biofertilizer to the soil increased cabbage yield. The quadratic regression model data show that plant yield was increased from 4,286.2 kg ha -1 in treatments without biofertilizer application to 17,132.1 kg ha -1 with the application of biofertilizer at concentration of 63.13%. Such increase represents a superiority of 299.7% between treatments without and with the adequate application of the input (Figure 4). Source: Authors.
According to Zandonadi et al. (2014), the supply of nutrients through organic fertilizers such as bovine biofertilizer improves soil conditions, causing stimulating effects on plants, with a positive result in the increment of yield. The average cabbage production in Brazil is between 20 and 35 t ha -1 , higher than the values obtained in the present experiment. In Roraima, according to Luz et al. (2002), Sooshu hybrid cabbage in dry season reaches up to 21 t ha -1 , which is similar to the yield found in the treatments with application of bovine biofertilizer at concentration of 63.13%.

Conclusion
Under the experimental conditions, application of bovine biofertilizer at dose of 63.13% increases the mass of leaves that form the head and the yield of Sooshu hybrid cabbage.
Addition of bovine biofertilizer to the soil increases the quality attributes of Sooshu hybrid cabbage.
There is no effect of the connecting rod system on the production components of cabbage produced in the savanna of Roraima.