Growth, Yield and Nodule Activity of Phaseolus vulgaris L. as Affected by Soil Moisture

Abstract

AbstractA study evaluated the response of two varieties of beans (Phaseolus vulgaris L.) to different soil moisture levels during a dry season. The soil moisture regimes maintained throughout the growth period were field capacity, 70–75 %, 50–55 % or 20–25 % available soil moisture.Plant growth, yield and nodulation were optimal when plants grew at high soil moisture levels. With increasing stress, all measured parameters of both varieties were reduced. However, polebeans, with its vine type of growth was affected to a greater degree than bushbeans. In contrast, nodulation and nodule activity of both variables was affected by moisture stress.A second experiment evaluated the effects of different soil moisture levels over the growth cycle of bushbeans, which produce greater yields under drier conditions. The highest yields were obtained at higher moisture levels throughout the growth cycle. Moisture stress up to flowering reduced yields to a greater extent than when the plants were subjected to reduced soil moisture after flowering appearance. Some casual mechanisms of the results of the experiments and possible implications for incorporating this popular vegetable legume in rainfed agricultural systems are presented.