Responses of faba bean (Vicia faba) to different levels of plant available water: I. Phenology, growth and biomass partitioning.

The present study was conducted under glasshouse condition to assess the effect of different levels of plant available water (PAW) on phenology, canopy development and biomass accumulation. Five levels of PAW were imposed on faba bean plant cultivar Maris Bead. Germination and flowering were significantly delayed under low PAW particularly 20% and 40% PAW i.e. 4-7 days and 23-33 days after sowing compared to the control (100% PAW). Low PAW has little effect on first pod development and maturity. Growth duration from germination to maturity was also reduced under low PAW (20%). In the absence of water stress i.e. 60, 80 and 100% PAW,longer duration from germination to maturity allowed the plant to develop a larger canopy resulting in high final total biomass i.e. 40, 60 and 90 g per plant while 20% and 40% PAW produced only 10 g and 25 g per plant respectively.