Genotypic Differences in Agro-Physiological, Yield and Yield-Related Traits Responses to Saline Field Environment for Rice Genotypes through Line x Tester Analysis

Rice is confronted with various abiotic stress factors during growth due to the challenges presented by global climate change, which poses a major risk to overall productivity and development. Salinity is considered the most serious abiotic stress that significantly affects yield stability among all other factors. Twenty-four hybrids generated from the combination of six lines with four new introgression testers were assessed along with their respective parents for the extent of physiological and yield potential-related traits under saline field conditions. A wide range of variability was observed among genotypes, the magnitude of SCA variance was higher than the GCA variance for all the traits, revealing the predominance of non-additive gene action. The promising line GZ 10101-5-1-1-1 was identified as a potential good combiner genotype for peroxidase, superoxide dismutase, proline, malondialdehyde, and hydrogen peroxide contents. Furthermore, it was found that Giza 178, Sakha 104, AR 278-41-1-1-6-3, and IHL 296 were effective general combiners for improving grain yield. Three cross combinations Giza 178/IHL 180, Sakha 104/IHL 296, and Sakha 109/IHL 185 exhibited favorable SCA effects for antioxidant enzyme activity. The cross-combination Sakha 104/IHL 249 was considered a good specific combiner for yield and certain yield-related traits. The highly positive significant heterobeltiosis was observed for antioxidant enzyme activity, malondialdehyde, and hydrogen peroxide concentrations by the cross-combination AR 278-41-1-1-6-3/IHL 185. In addition, the hybrid combinations Giza 178/IHL 296, Sakha 104/IHL 180, and Sakha 104/IHL 296 were found to have highly significant heterobeltiosis effects for yield and related traits under a saline field environment.