Genetic analysis of drought tolerance in maize (zea mays l.) Using diallel method

Drought stress is one of the factors which damage corn production in many countries and also in Iran, therefore, breeding for tolerance to drought stress has become a major focus in Iran maize program. In the present investigation, combining ability, gene action and genetic analysis of five characteristics including ear diameter, grain yield, ASI, ear length and 1000kw weight were studied in six pure lines of maize and their fifteen hybrids (twenty-one genotypes). The materials were evaluated in two different experiments using a RCBD with three replications in two environments (water stress and normal irrigation) in Safiabad Agricultural Research Center. Data were analyzed with method two and mix-model B of Griffing. Hayman method was used only for graphical and genetical analysis of ear length. Significant differences were observed among enotypes for different traits in both conditions. Based on the results, the dominance variance was responsible for controlling ear diameter, grain yield, anthesis- Silky interval, ear length and 1000kw weight in both conditions, therefore breeding procedures based on inbred lines generation and then cross between them to find the best materials would be important. Generally, in non-stress condition the additive and dominance variances were involved together, but in stress condition the dominance variance was more important than additive variance.