Irrigation Systems, Fertigation and Mulch: Effects on the Physical, Chemical and Biological Attributes of the Soil with Banana Crop in Northeastern Brazil

Abstract

ABSTRACT The banana crop is extremely demanding of nutrients and quite sensitive to soil-related growth factors. A field experiment was set up to evaluate the effect of irrigation and soil-cover management on the physical, chemical, and biological attributes of an Oxisol cultivated with banana, in Northeast Brazil. We tested two irrigation systems (drip or microsprinkler) and two types of fertilizer application (manual or fertigation). At the same time, the effect of mulch as soil-covering was assessed. The experimental design was of randomized blocks, with four replications. The soil attributes were evaluated: total porosity; macroporosity; microporosity; bulk density; pH in water; exchangeable P, K, Ca, Mg, and Na contents; potential acidity; total soil organic carbon (C); basal soil respiration; microbial biomass C and phosphatase activity. The irrigation system and mulch cover did not significantly affect the physical attributes of the soil. The combined management of banana mulch and fertigation increased the levels of P, K, Cations exchange capacity, and organic C over the two years of cultivation, besides reducing the levels of exchangeable Na. Cultivating the banana under drip fertigation and using mulch from banana biomass improved the chemical fertility and increased the microbial activity of the soil. The use of mulch tends to standardize the possible differences in the phytotechnical parameters of the banana between the drip irrigation and microsprinkler systems.