Influência da aplicação de esterco bovino no estado nutricional de Moringa oleífera LAM., nas propriedades químicas e microbiológicas do solo.

Abstract

Moringa oleifera is an exotic species widely found in the Brazilian semiarid region, it stands out for its adaptation to the conditions of the region and for its diverse uses. However, information about the nutrition of M. oleifera and the characteristics of soils cultivated with this species are still scarce. Thus, the objective of this work was to evaluate the effect of different doses of bovine manure on the foliar nutrition of M. oleifera and on the chemical and microbiological properties of the soil. The experiment was conducted in the field in the period from December (2018) to June (2019), in the city of São José do Bonfim PB. The experimental design was in randomized blocks with five treatments (D0=control, D30=30g kg1, D40=40g kg1, D50= 50 g kg1 and D60=60 g kg1) and five repetitions. Leaf and soil samples were collected during the flowering and fruiting period of M. oleifera. From the leaf samples the contents of macronutrients (N, C, P, K, Ca, Mg, S and the C/N ratio) and micronutrients (B, Cu, Fe, Mn and Zn) were evaluated. The soil samples were evaluated for chemical (pH, H+Al3+, P, K+, Al, Ca2, Mg2+, cation exchange capacity (CTCefetive), base sum (SB), base saturation (V%), total organic carbon (TOC), Cu, Fe, Mn and Zn) and microbiological (microbial biomass carbon (MBC), soil basal respiration, metabolic quotient, microbial quotient and activity of the enzymes βglucosidase, phosphatase, urease, βglucosaminidase and dehydrogenase). The use of bovine manure influenced the chemical and microbiological properties of the soil and the contents of macro and micronutrients in the leaves of M. oleifera. In general, the pH, Mg, K, P, SB, V% and CEC values of the soil increased with the application of bovine manure compared to the D0 dose. Significant variations were observed in Fe, Zn and Cu contents, while Mg did not show significant difference. The results obtained for microbiological properties show that the application of bovine manure influenced the soil microbial biomass and activity. The CBM, phosphatase, βglucosidase, βglucosaminidase and βglucosidase/ Urease ratio showed an increase with manure application. In relation to the macro and micronutrients in the leaves of M. oleifera, a reduction in N content was observed starting with the dose D_40 and an increase in C and the C/N ratio (D_60), Mg, S and B. For the foliar contents of P, K and Zn no significant differences were observed among the doses. The application of different doses of manure promotes distinct effects on soil biomass and microbial activity and on foliar nutrition of M. oleifera, however, it is highlighted that the application of manure is favorable to soil health and can contribute to nutritional improvement of M. oleifera.