Effect of Drought Stress on Different Maize Genotypes

In order to study the effects of drought stress on yield and yield components of 16 medium and late maturing maize hybrids a field trial was conducted under non-stress and different drought stress conditions (stress at vegetative, reproductive and grain filling stages) at Miyandoab Agricultural Research Station of Iran. The experiment was arranged in group balanced blocks as a split plot design with three replications. During the growing season some agronomic, morphological, physiological and phenological traits such as 300 kernel weight, number of kernels per row, number of kernel rows and anthesis-silking interval (ASI) were measured. Analysis of variance and mean comparisons showed that there was a significant diversity among the studied hybrids. The yield decreased under drought stress at reproductive stage was greater than the other stages. The estimation of phenotypic correlation coefficients, stepwise regression and path analysis were done under non-stress and different water stress conditions. Path analysis showed that selection of genotypes will be more effective based on 300 kernel weight, number of kernels per row, ear length and plant height under non-stress condition and shorter ASI and days to silking emergence, larger percentage of green cover and greater number of kernels per row under drought stress conditions