Risco térmico por altas temperaturas para a cultura do feijoeiro

Abstract

The consumption of beans is fundamental mainly due to the fact that it is rich in protein, much cultivated by the Brazilian family farmer and it is configured as a subsistence crop and that it uses little technology in its cultivation. It presents a high susceptibility to temperatures above 28 ° C in reproductive periods, which may cause abortion or senescence of part of the plant, such as flowers, already formed pods and leaves, due to the fact that the high temperature to unleash the synthesis of ethylene in the plant. The agroclimatic zoning for culture does not emphasis on the temperature of the air, which affects the crop. With these pretext, the objective of this work was to evaluate the thermal risk for the bean crop in Cruz Alta, Passo Fundo and São Luiz Gonzaga. With a simple methodology, three cities in the state of Rio Grande do Sul were selected because they presented significant yields of beans and meteorological stations to obtain data. With the result that, from the data of maxim air temperature, day when it reaches 28 ° C is considered an unfavorable day. The year was divided into period of ten days, totaling 36 period of ten days, with about 44 years of data obtained from the Banco de Dados Meteorologicos para Ensino e Pesquisa (BDMEP) and thus calculating the mean and frequency of unfavorable days for each period ten days. The period of bigger thermal risk was found in the third of period the ten days of January for cases and the first three of the period ten days present the periods of bigger thermal risk and Passo Fundo presented the better thermal condition for bean cultivation. São Luiz Gonzaga, even during periods not indicated for the culture, during the winter season, still presented chances (even very low) of happen a day of high temperature.