Coinoculação com Bradyrhizobium elkanii e Azospirillum brasilense associada à aplicação de silício em cultivares de feijão-caupi

Abstract

Plants grown under rainfed conditions and in the off-season are subject to several morphological and physiological disorders. Therefore, practices that enable better use and efficiency of water use combined with greater absorption of nutrients, such as nitrogen, are essential. Thus, the use of diazotrophic bacteria associated with the application of silicon can mitigate the harmful effects that harm the good productive performance of cowpea. Therefore, the study aimed to evaluate the effects of coinoculation with the bacteria Bradyrhizobium elkani and Azospirillum brasilense combined with the application of Si on the productive performance of cowpea cultivars. The study was conducted at the IFPI School Farm - Uruçuí campus, in an experimental design in randomized blocks with four replications, in a 2 x 4 split plot scheme, the plots corresponding to cowpea cultivars (BRS Novaera and BRS Tumucumaque) receiving inoculation pattern of Bradyrhizobium elkanii and the sub-plots consisting of four treatments: control, silicon, Azospirillum brasilense and silicon + Azospirillum brasilense. The following traits were evaluated: plant height, stem diameter, root fresh mass, root dry mass, number of pods per plant, number of grains per pod, thousand-grain weight and grain productivity. Coinoculation of seeds with Azospirillum brasilense increased the performance of fresh root mass and grain yield in the BRS Novaera cultivar. The use of Azospirillum brasilense alone proved to be the most efficient strategy in increasing the cultivar's grain productivity in relation to the control treatment