Optimizing irrigation frequency and amount on yield and water productivity of snap bean (Phaseolus Vulgaris L.) in NW Amhara, Ethiopia: A case study in Koga and Ribb irrigation scheme

This study has investigated the effects of different irrigation frequency and depth on yield and water productivity of snap bean at Koga and Ribb irrigation scheme, NW Amhara, Ethiopia. It was done in a factorial experiment laid out in split-plot design with three replications of two irrigation intervals and five variable irrigation depths. Irrigation depth had shown a significant effect on marketable pod yield, and irrigation water productivity whereas irrigation frequency hadn't shown a significant effect. The interaction effect hadn't shown a significant effect on marketable pod yield and response for irrigation water productivity of snap bean at Koga. At Koga, the application of 75% ETc gave an optimum marketable yield of 10.66 t ha(-1) and irrigation water productivity of 2.89 kg m(-3). At Ribb, marketable pod yield and irrigation water productivity had no significant effect on irrigation frequency while marketable pod yield and irrigation water productivity had shown a significant effect on irrigation depth and the interaction effect. At Ribb, the application of 100% ETc gave an optimum marketable yield of 13.16 t ha(-1) and irrigation water productivity of 2.69 kg m(-3). Therefore, to attain an optimum yield and water productivity, at Koga and Ribb snap bean can be irrigated with 75% ETc and 100% ETc at 7 days irrigation interval respectively.