Influence of soil water avallability on the bean plant efficiency in utilizing water and solar radiation

Abstract

This study aimed at observing the influence of available variation on the efficiency of two bean (Phaseolus vulgaris L.) varieties (Aroana 80 and Aetá 3). Two different sowing times (time interval of 15 days) were used. Irrigation was suspended over a 17 days period when plante of the first plots were at pod formation and development stage, and plante of the second plot at bud formation stage. A treatment with bigh values of available water over the whole growing period, was also included. The two different varieties were observed within the following parameters: water consumption, (water balance, tensiometer method), phenology, leaf area index, incident solar radiation, dry matter and calorimetric contente in aeriai biomass and plant efficiency concerning conversion of wáter and solar radiation into energy and biornass. The cv. Aeté 3 showed higher efficiency in the parameters studied compared to the cv. Aroana 80. Water deficit treatment was less efficient than the treatment without water stress. Energy content of biomass componente varied during the culture cicle and related to the soil unit levels