Effect of fertilization with basalt powder and inoculation of Bradyrhizobium spp in common bean

Abstract

The common bean is a legume capable of performing biological nitrogen fixation (BNF). The objective of this work was to evaluate the effect of the application of rock powder associated with inoculation of Bradyrhizobium spp. in isolation or associated on the relative chlorophyll index in common bean leaves. Two experiments were conducted at the Federal Institute of Paraná Campus (IF-PR) in Ivaiporã- PR with four treatments and four completely randomized replicates. The treatments were: Inoculation of seeds with Bradyrhizobium spp; Inoculation of Bradyrhizobium spp. with basalt application; basalt application and control. The chemical analysis of the soil was performed. The seeds were inoculated with MasterFix based on Bradyrhizobium spp. following the manufacturer's recommendations. The relative chlorophyll index (IRC) was evaluated after the opening of the second trifoliate leaf. The IRC in experiment 1 was evaluated at 23, 38 and 53 days after sowing. In experiment 2, the IRC of the plants was evaluated at 25 and 41 days after sowing. The significant effect of treatments at 38 and 53 DAP was verified in relation to IRC, when the plants were cultivated with application of rock powder associated or not with Bradyrhizobium spp. There were treatment effects in relation to IRC in plants inoculated with Bradyrhizobium spp. and inoculated with Bradyrhizobium spp associated with rock powder, when compared with basalt powder and control.  There was benefit of increased IRC in both treatments inoculated with Bradyrhizobium spp.