VARIATION IN PERFORMANCE OF SOME MAIZE GENOTYPES UNDER WATER STRESS CONDITIONS AT DIFFERENT GROWTH STAGES

Abstract

The expected future shortage in irrigation water in Egypt necessitates that maize breeders should pay great attention to develop drought tolerant maize cultivars. Maize is particularly susceptible to drought at the flowering stage. Tolerant genotypes of maize were characterized by having shorter anthesis-silking interval (ASI), more ears/plant and greater number of kernels/ear. Drought tolerance might be increased by improving the ability of the crop to extract water from the entire soil profile. Roots are the principal plant organ for nutrient and water uptake. Maize ability to grow deep roots is currently the most accepted target trait for improving drought tolerance. The presence of genotypic differences in drought tolerance would help plant breeders in initiating successful breeding programs to improve such a complicated character. Strong associations between agronomic, physiologic, root traits and drought tolerance, high heritability and high genetic advance for such traits would allow plant breeder to use such traits as selection criteria for selecting drought tolerant genotypes.