Effect of organic fertilization on agronomic variables of black beans (Phaseolus vulgaris L.) in El Cercado area, Duarte province, Dominican Republic

Abstract

Beans (Phaseolus vulgaris L.) are widely planted in the Dominican Republic and constitute one of the main sources of vegetable protein and calories consumed by the population. However, in the country the effects of applying compost to the soil on the agronomic variables of the beans are unknown. From March to June 2015, this effect was evaluated in bean in El Cercado area, Duarte province, Dominican Republic using a randomized complete block experimental design with seven treatments: 0, 1 500, 3 000, 4 500, 6 000, 7 500 and 9 000 kg ha^-1 of compost with four repetitions per treatment, on the of beans DPC-40 variety. The variables evaluated were grain yield, silver height, dry weight of foliage, dry weight of roots, number of pods per plant, number of grains per pod, cost-benefit ratio, and analysis of foliage and root components. The data was subjected to analysis of variance and linear regression analysis. High significance was obtained for the variables yield, plant height and number of grains per pod, while the other variables were not significant. The analysis of foliage and root components for heavy metals (Ni and Cr) did not present high levels. Thus, the application of compost has a positive correlative effect on yield, plant height and the number of grains per pod, and has no effect on foliage weight, root weight and number of pods per plant. In addition, it was found that the application of compost to the soil has a return rate of 84.18 DOP for each DOP invested, so its application is recommended.