Short Communication: Effect of drought stress on maize hybrides yield and determination of the best hybrid using drought tolerance indices

In order to study the effect of drought stress on according to irrigation intervals (7days and 10days) on grain yield of four maize single cross hybrid (500، 647،700 and 704) a split plot experiment based on randomize complete block design with 3 replications was done at Khatam during 2009. Plant height، number of row in ear، number of grain in row، number of grain in ear، ear length، ear diameter،ear wood weight، 1000 grain weight، biological yield، grain yield and harvest index were measured. The results showed that drought stress caused a significant decrease on all traits and decreasd grain yield 10. 2 to 5. 5 ton/ha. It was significant different between hybrids in grain yield. The highest grain yield was produced by KSC704 (11. 2 ton/ha) and lowest grain yield was produced by KSC500 (3. 9 ton/ha). The highest MP، GMP، STI and the lowest TOL and SSI indices was for KSC704 that indicated KSC704 is the most resistant hybrid to drought stress.