Effect of moisture stress level on yield and water productivity of common bean (Phaseolus vulgaris L.) at Melkasa, Central Rift Valley of Ethiopia

Abstract

A field experiment was conducted in Ethiopia to investigate the impact of different irrigation water levels on common bean yield and water productivity under limited water resources. The experiment involved 7 moisture levels ranging from 100 to 35 % of crop evapotranspiration. The results showed that grain yield decreased as water stress increased, with the highest grain yield of 3004 kg ha-1 achieved at 100 % ETc and the highest water productivity of 1.16 kg m-³ at 35 % ETc. Dry biomass, harvest index, and 1000 seed weight were also affected by water stress. However, the grain yield obtained with 75 % ETc did not differ significantly from the yields obtained with 85 or 100 % ETc. Similarly, the weight of 1000 seeds and pods per plant did not significantly differ between 75, 85, and 100 % ETc. The water productivity observed at 75 % ETc was significantly higher than at 85 and 100% ETc. Therefore, the study suggests that the common bean variety SER-119 can be irrigated at 75 % ETc to increase water productivity without a significant reduction in yield and yield components in a water-stressed environment.