Impact of Molybdenum Foliar Application on Black Bean Development and Seed Production

Bean is a crop of great importance to Brazilian agriculture, due to their relevance for population diet and also as it is one of the countries that produces and consumes more beans. However, their production remains low and one of the reasons may be the failure in absorbing the most of the fertilization applied. Therefore, research is needed to find ways to ensure maximum efficiency and absorption of nutrients by plants, such as the use of Molybdenum application via foliar. The objective of the work was to evaluate the development and yield of beans with foliar application of Molybdenum. The experiment was conducted in randomized blocks in a 2 x 4 x 3 factorial scheme (sowing season x doses x application time), with treatments consisting of two sowing season: autumn/winter (sowing in February - dry season) and spring/summer (sowing in October – rainy season), four Mo doses (0, 50, 150 and 300 ml ha-1 of commercial Mo based product) and three application times, starting the count after 50% plant emergence (10 days after emergence – DAE, 20 DAE and 30 DAE). The experiment was performed at the Experimental Farm of the Grand Dourados Federal University, at the municipality of Dourados, MS, Brazil. The Mo source was a commercial product with a concentration of 216 g l-1 Mo. Black beans were sown using a conventional procedure, with soil preparation by subsoiling, harrowing and leveling. A pneumatic seeder was used with a spacing of 0.45 m, 12 seeds per meter of furrow, in plots of 5 x 5 m, totaling 10 plants per meter, a population of 222,222 plants ha-1 and depth of 0.02 m. For the agronomic evaluations, five plants per plot were collected at the end, when the crop reached physiological maturity, in the central line, for the following determinations: number of pods per plant; number of seeds per plant; number of seeds per pod; mass of a thousand seeds and yield. Positive Results in yield components and effective yield of black-beans were found when 50 ml ha-1 of molybdenum was applied via foliar application. Although it was not one of the objectives of the study, it was concluded that the amount of rainfall in the crop cycle affects the action of molybdenum on bean plants.