Nodulation and grain yield of cowpea in response to molybdenum

Abstract

The application of micronutrient, such as molybdenum (Mo), can be important to increment biological N₂ fixation and yield of cowpea. This work aimed to evaluate, in field conditions, the effect of Mo application on nodulation, plant growth and yield in cowpea (BRS Guariba) at Teresina, PI. The treatments were disposed in a completely randomized block with five rates of Mo, in FTE form (0; 30; 60; 90 e 120 g ha^-1 de Mo). The inoculation was conducted using Bradyrhizobium elkanii, strain BR 3262. Number of nodule, nodule dry weight, shoot and root dry weight and N content in the shoot´s dry matter were determined 36 days after plant emergence (DAE). Grain yield was determined 58 DAE. Differences were not verified among the treatments to root and shoot dry weight. N content in the shoot´s dry matte and grain yield were higher with Mo application. The inoculation of seeds associated with Mo favor the nodulation and N content increasing grain yield in cowpea.