Gen action for yield and yield component under salinity stress in bread wheat. – a review.

A salinity stress problem is defined as a condition where the salts in solution within the crop root zone accumulate in high concentrations, which decrease crop yield. Bread wheat (Triticum aestivum. L) is a moderate to salinity tolerance crop Salinity susceptibility index (SSI) become widely used by researchers to identify sensitively and resistant wheat genotypes and increase wheat yield is to improve the salinity tolerance of genotypes. Heterosis represents the percentage of augmenting or decrease in the mean value of the F1 hybrids over their mid-parents’ value. The heterosis represents the percentage of increase or decrease in the mean value of F1 hybrid over a better parent. Knowledge of broad-sense heritability (h2 b.s), narrow-sense heritability (h2 n.s), general combining ability (GCA), and specific combining ability (SCA) is useful in the choice of parental genotypes. Combining ability studies assist in the identification of parents with greater GCA values and parental combinations with greater SCA values. High heritability values of the type, which give salinity tolerance in wheat, fixed that a major advance in salinity tolerance may be possible through selection by the order of high selection pressure. The additive and nonadditive gene action played a major role in controlling for traits of wheat under normal conditions and salinity