Effect of water stress and potassium chloride on biological and grain yield of different wheat cultivars

Water stress is the main restriction in and and semi-arid for agriculture around of the world. Although all cropland in Sistan and Baluchestan province of Iran are cultivated under water irrigation, frequently at the end of growth season, i.e during the beginning of the grain filling period, crops are exposed to water deficiency. To determine the effect of water deficiency and application potassium chloride (KCL) on biological and grain yield of two wheat cultivars, Falate and Hermiand were cultivated under field conditions at Sistan. The experiment was carried out during 2003-2004 growing season at RCI of Zabol under three irrigation levels (full irrigation, stop irrigation after pollination and after milky stage of grain) and three levels of KCl solution (control-without application of KCL solution, application of KCL solution at appearance of first spikelet 10.5-1 Fix scale and at milky stage of grain 10.5-5 Fix scale). A split-split plot design was used where the main plot was irrigation, sub plot cultivars and the KCL application as a sub-sub plot. Three replicates per treatments were used. The results showed that biological yield was significantly affected by water stress in both wheat cultivars, but treatments, had no significantly effect on number of grain per spike. Harvest index and thousand-grain weight were significantly effected by water stress and wheat cultivars. In addition, grain yield was only affected by water stress. Potassium chloride treatment had no effect on biological and grain yield.