Effect of Water Regimes and Polyvinyl Alcohol on Faba Bean Yield, Chemical Composition and Water Use Efficiency

Abstract

Quantifying local crop response to irrigation is important for establishing proper irrigation management approaches.To apply that, a field experiment was carried out to evaluate the effect of three available soil moisture depletion(ASMD) levels, 25 %, 50 %, and 75% applied using solid set sprinkler irrigation system in combination with four concentrations (0.00%, 0.05%, 0.1% and 0.2 %)of poly vinyl alcohol soil conditioner. The combined effect of water regimes and different concentrations of soil conditioner was studied on faba bean (Vicia faba cvGiza 843), The experiment was carried out in the semiarid climate of northeast Farm of El-Ismailia Agricultural Research Station, El-Ismailia Governorate Egypt during two successive seasons(2012/2013 and 2013/2014).Evapotranspiration (ETa), yield productivity of faba bean, water use efficiency and macronutrients uptake were also evaluated. Results showed that the actual seasonal crop evapotranspiration (ETa) for ASMD treatments varied between (1605.36 –2482.45m3 fed-1.) in the first season (2012/2013) and (1439.26 – 2457.01m3 fed-1.) in the second season (2013/2014). There are three options to calculate seasonal ETc for faba bean crop in Ismailia condition. So, it can be use FAO-24RD, PMd or Droogers and Allen (2002)methods. Moreover,obtained data reveal that application of polyvinyl alcohol(PVA)synthetic soil conditioners (with high concentration), decreased available soil moisture depletion (ASMD) in sandy soil and caused a significant increase in faba bean yield, water use efficiency (WUE) and improved the macronutrient uptake by faba bean yield. Finally, the results clearly showed that the significant effect of PVA at (0.1or 0.2 %) concentration was most observed at 50% ASMD.