Reaction of phonological characteristics of granular corn hybrids to drought tension

In order to investigate the phonological characteristics of new hybrids of corn in drought tension, this experiment as a complete randomized block design in a strip-plot arrangement was done at the research field of University of Agriculture and Natural Resources of Ramin Khouzestan in 2010-2011. It included three levels of irrigation regime (irrigation cut-off in 8-leaf stage, irrigation cut-off in stage of male flower appearance and optimum irrigation) in longitudinal plots and 11 hybrids (07-101, 07-103, 07-107, PL710, PL711, PL706, PL774, AS71, Mobin, Karoon and S.C 704) in transversal plots with three replications. The results showed that irrigation cut-off in 8-leaf stage (vegetative stage) caused duration of vegetative growth to last longer, whereas it postponed starting of generative growth, so that the longest duration of vegetative growth was obtained for hybrid 07-107 in tension conditions in 8-leaf stage and the shortest duration happened to hybrid PL706 and in non-tension conditions. Duration of generative growth of different hybrids was influenced by the amount of water received by plant of course this change happened more intensely in drought tension treatment in stage of male flower appearance. The longest duration of generative growth was obtained for hybrid PL706 in optimum irrigation conditions and the shortest duration was obtained for hybrid AS71 in drought tension conditions in stage of male flower appearance. Duration of pollination of different hybrids was affected by the degree of plant access to water. The longest duration (11.17 days) of pollination was obtained for hybrid PL706 in non tension condition and the shortest duration was observed for 07-101, 07-103, AS71, PL710 and PL711 hybrids all the same in 3.67 days in irrigation cut-off conditions in stage of male flower appearance. The trend of the variations in duration of flowering indicated that this duration was longer for all hybrids in optimum irrigation conditions, whereas it was shorter in tension conditions in stage of male flower appearance and Interaction drought tension and hybrid on duration of flowering adaptation was significant.