ESTIMATION OF GENETIC COMPONENTS FOR VARIOUS PHYSIOLOGICAL TRAITS IN MAIZE (Zea mays L.) UNDER WATER DEFICIT CONDITIONS

Drought is a solemn environmental factor that causes great loss of yield in maize crop. Maize is highly sensitive to drought. There is need to develop drought tolerance maize genotypes to fulfill demand of feed for livestock and food for human. For this propose prescribed study was conducted to estimate genetic components for various physiological traits under normal and water tress conditions in the research area of the Department of Plant Breeding and Genetics, University of Agriculture Faisalabad, Pakistan. It was concluded that P1 (WFTMS) parent performed better under drought conditions for stomata frequency, stomata conductance, stomata size, cell membrane thermo stability, leaf water potential and excised leaf water loss while BC2 for stomata conductance, F1 for stomata size, F2 leaf water potential and BC1 for leaf temperature. Positive [h] dominance effects were recorded for cell membrane thermo stability, stomata frequency and leaf water potential while [d] additive effects for leaf water potential under normal conditions. It was reported that [i] additive × additive interaction were found for cell membrane thermo stability, stomata frequency and excised leaf water loss while negative for leaf water potential under normal conditions while under drought for cell membrane thermo stability, stomata frequency, stomata conductance and excised leaf water loss. It was suggested that the traits showed [d] additive and [i] additive × additive interaction may be used to fix the increase in the expression of traits in next generations and selection for the development of synthetic varieties for drought resistance may be helpful. The [h] dominance effects showed that the traits may be used for the development of hybrid. On the basis of genetic effects it was concluded that stomata frequency, stomata size, cell membrane thermo stability, leaf water potential and excised leaf water loss may be helpful for