Análise do crescimento e produtividade econômica do feijoeiro irrigado na região de Alegrete, RS

Abstract

The cultivation of beans has global importance, both in terms of economic development, as the social character. It is grown in the most diverse types of productive systems, and in practically all Brazilian territory. However, it is still considered to many regions, such as subsistence crop and produced by family farmers. Among the factors of production that most influence on the success of productive and quality of crops, the water deficit is among the most aggravating. However, both the water deficit as water excess can be harmful to bean crop. The region of Alegrete, RS presents great potential for bean production, considering the average rainfall occurred in the growing months. However, the poor distribution of the precipitation during the phenological stages of the crop, can result in reduction of the production. In this way, along with the other factors of production, irrigation becomes a strong allyin water supplementation, during critical periods, aiming for the crop to develop and reach its maximum productive potential. In this context, the objective of this study was to evaluate the influence of the application of different irrigation levels on the components of growth, development and productivity of bean crop, cultivated in border west region of RS. The experiment was carried out in a greenhouse at Universidade Federal do Pampa - Campus Alegrete - RS in the period from February to July 2016. It was used the cultivar BRS Valente. Treatments were arranged in a completely randomized design with four replications. The management of irrigation was based on fixed watering shift of four days, and the amount of water applied was stipulated based on crop evapotranspiration (ETc), the product of reference evapotranspiration (ETo) and the crop coefficient (kc). The irrigation treatments were: 25, 50, 75, 100 and 125% of replacement of ETc. During the bean crop cycle has bean measured the growth and development components of plants as plant height, stem diameter and leaf area index. At the end of the crop cycle, production components were evaluated: number of plant pods, number of pod grains, average weight of grain, grain yield and production of dry matter and water productivity. Also the harvest index were determined and the economic great level of irrigation for the crop. Irrigation applied under 100% of ETc replacement maximizes the grain production of beans in region of Alegrete, RS, found for the climate and soil conditions in which this experiment was conducted.