RESPONSE OF SEVEN VARIETIES OF BREAD WHEAT (Triticum aestivum L.) TO WATER STRESS

Abstract

ABSTRACT :A field trial was conducted in the winter season of 2012 – 2013 at AL-Mahanwiyah experimental farm which belongs to the extension training center –Babylon governorate (Latitude North and East). The objective was to investigate the effect of water deficit on the growth and yield of seven wheat cultivars (Triticum aestivumL.) . This trial was arranged as a split plot in the Randomized complete Block Design with three replicates . Treatments at irrigation (irrigation after 50% depletion of available water (S0) , irrigation after 75% depletion of available water (S1) and irrigation after 90% depletion of available water (S2) )occupied the main plots . While varieties occupied the sup-plots .water deficit ( stress ) caused a significant reduction in the grain yield components , but moderate stress had no effect on 1000 grain weight compared with the full irrigation .water stress caused a significant reduction in the grain yield , biological yield and harvest index compared with the full irrigation . Also it reduced water use efficiency of both grain and biological yields .Al_Izz was superior in the awn characteristics ( length , weight and numbers ), while cham -6 the lowest values .Al_Furat had the highest values of spike number . m-2 with the lowest value for Tammouz-2. Al_ Iraq was superior in the grain .spike-1and 1000 grain weight . However ,Al_Furat gave the lowest values ,N70 was superior in the grain yield .