Gamma Ray Induced Genetic Variation Enhances Biomass Production, Salinity Tolerance, and Nutritional Quality in Desmanthus virgatus M3

Desmanthus virgatus is a promising forage legume with high nutritional quality and good adaptive capacity; however, its utilization on highly saline soils remains limited. This limitation highlights the potential for developing breeding programs based on genetic diversity to produce adaptive and high quality genotypes. This study aimed to evaluate the agronomic, physiological, yield, and nutritional traits of gamma ray induced D. virgatus M3 mutant lines under saline conditions, to estimate variance components and heritability, and to analyze correlations among agronomic traits and yield components. The experiment was conducted using a completely randomized design with thirteen gamma irradiated mutant genotypes and three replications. The results demonstrated significant genotypic variation for nearly all observed traits, except leaf abscission. High heritability estimates for most traits indicate strong potential for trait transmission to subsequent generations. Dry biomass production exhibited strong positive correlations (P<0.05) with leaf and pinnae related traits, particularly number of compound leaves (r = 0.79) and number of pinnae (r = 0.77), as well as with crude protein and fiber content, while being negatively associated with leaf shedding, crude fat and total digestible nutrients, indicating a close linkage between biomass production and structural as well as nutritional traits. These findings suggest that agronomic, physiological, and nutritional traits play critical roles in supporting forage productivity of D. virgatus under high salinity stress conditions.