Most of the crops are sensitive to water deficits, particularly its may caused means of grain yield reduction 50 percent (Sarvestani et al., 2008).
the cultivars that is flower late was more susceptible to drought and reduce low yield, the panicle was not completely to exert panicle remain in flag leaf sheath and the spikelet on the panicle were completely sterile (Pantuwan et al., 2002a).
Drought stress most severely impact yield when occurred during the reproductive stage (Sheng et al., 2004)