Crescimento, produtividade e rendimentos financeiros do feijão comum irrigado.

Abstract

The bean responses to different irrigation levels is essential to estimate the financial returns of this crop and irrigation systems. Therefore, this research aimed to evaluate the growth, agricultural productivity and financial returns of the irrigated bean cultivation, in the Zona da Mata of Alagoas. The experiment was carried out from 11/17/2015 to 02/01/2016 at the Campus of Engineering and Agricultural Sciences (CEAS) of the Federal University of Alagoas (UFAL). The treatments were six levels of irrigation, in function of the evapotranspiration of the crop - ETC (25%, 50%, 75%, 100%, 125% and 150% of ETC). And, the analyzed growth and production variables were: plant height, dry mass, leaf area index (LAI), number of pods per plant, weight of 1000 grains and agricultural productivity. The bean production cycle lasted 77 days. During this period, the accumulated rainfall was 291.6 mm, with a daily average of 3.8 mm, but irregularly distributed. The maximum LAI, estimated by the normal Pic Log model of 3 parameter, was 7.1 at 41 days after the planting (DAP); the maximum plant height (61.9 cm) and the highest number of pods per plant (17.3 pods), determined by the normal Pic Log model of 3 parameter, were observed in areas irrigated with 125% of the ETC, irrigation depth total of 323.0 mm; the highest dry mass of plants, estimated by the same model, was 218.1 g per plant, in treatments of 150% ETC; the weight of 1000 grains was 215 g, with no significant difference between the treatments. The maximum physical productivity of the irrigated common bean, in the Zona da Mata of Alagoas, is 2,183.4 kg ha-1, obtained with 304.0 mm of total irrigation depth; and the yield of maximum financial efficiency is 2,182.0 kg ha-1, with total irrigation of 300.0 mm.

Keywords: Irrigation depth; evapotranspiration; plant height; LAI.