Influence of different irrigation regimes and varieties onyield and water productivity of common bean under semi desert climatic conditions of Sudan

A field experiment was conducted at Hudeiba Research Station Farm, located at Ed-Damer, Sudan during 2011/2012 and 2012/2013 winter seasons to investigate the effect of different irrigation regimes and varieties on common bean (Phaseolus vulgaris L.)  yield, yield components and water productivity. The treatments included three irrigation regimes; irrigation every 10 days (I1= full irrigation), irrigation every 15 days (I2= moderate stress) and irrigation every 20 days (I3= severe stress) and two varieties (Giza3 & Ibraya). The treatments were arranged in factorial randomized complete block design (RCBD) with 3 replications. Irrigation water applied, grain yield, yield components (number of pods per plant, number of seeds per pod and the 100 seeds weight) and crop water productivity (CWP) and irrigation water productivity (IWP) were recorded. Results showed that number of pods per plant, number of seeds per pod, 100-seeds weight, grain yield and irrigation water applied  were significantly (p ≤0.001) affected  by irrigation regimes. The highest values of these traits obtained with full irrigation, whereas the lowest values recorded under severe water stress conditions. Results also indicated that, moderate and severe water stress regimes saved 591 m3 and 1075 m3 of irrigation water, respectively compared with full irrigation. . This study indicated that, treatment I1 that was irrigated every 10-days did not produce the highest IWP, while treatment I2 which irrigated every 15-days gave the highest IWP. The lowest IWP occurred at severe water stress regime (I3). It could be concluded that moderate water stress may be adopted. Contrarily, the adoption of severe water stress that produce high water savings would lead to yield losses that may be   economically not acceptable.
Giza3 was a superior variety under both full and deficit irrigation conditions, compared with Ibraya. This superiority was attributed to the higher number of pods per plant and higher number of seeds under all irrigation treatments. Giza3 significantly obtained (p ≤0.001) higher IWP and CWP.