الفهرس 
Combining ability and gene action.
Drought tolerance studiesOnly 14 pages are availabe for public view
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Abstract
In the majority of agricultural ecosystems across the globe, water stress is one of the leading causes of crop production decline. Breeding for drought tolerant genotypes is an important strategy to overcome this constraint. The degree of tolerance developed to confront water stress were examined through analysis variance, combining ability, heterosis, genetic parameter and heritability for all 22 selected trails in two environments. Also, the behavior of the selected rice genotypes was determined through biological, anatomical, and molecular responses under water stress. According to the results of the field during seasons of study, tremendous genetic variability among genotypes under normal and water stress conditions for various characters were observed. The additive genetic variance played the most important role in the inheritance of the traits and the selection might be practiced successfully in early generations. Based on the positive response of the biochemical analyses, genotypes Sakha 107× Sakha super 300 and Sakha 107 × M206 were considered tolerant genotypes for water stress. The promising crosses had higher values of several root-, stem-, and leaf- anatomical parameters than their parents when they were stressed by a water deficit. Molecular analyses were done by 10 ISSR primers, the two crosses recorded the highest similarity value and are also grouped in a distinct cluster. Also, under drought stress, the relative expression of four genes were significantly elevated in the most two drought-tolerant rice genotypes.