Correlation and Path Analysis of Yield and Seedling Vigour Related Traits in Wild Introgression Lines

Early establishment of crop plants are highly influenced by resource availability in its environment. Seedling early vigour refers to the ability of seeds to germinate quickly and uniformly, resulting in the robust crop establishment especially under stress environments. Modern cultivars which are bred for transplanting under irrigated conditions with semi-dwarf architecture lacks early seedling vigour, required under stress situations. Vigorous seedlings have additional advantage of better nutrient uptake by smothering weed plants and inhibit their growth. Improving rice plant architecture with high seedling vigour is a major breeding objective in the context of climate change effect. Backcross Introgression Lines derived from interspecific crosses were screened for seedling vigour traits and yield related traits and correlation analysis was employed to assess the trait association. Among all the 31 traits studied for correlation concluded that positively significant correlation was observed for panicle length, panicle weight, filled grains, total number of grains. Genotypic and phenotypic correlation revealed that the traits panicle length, panicle weight, filled grains, total number of grains, days to 50% flowering have shown significant correlation with single plant yield. Path analysis concluded that days to 50% flowering, number of tillers, fresh weight, dry weight, germination percentage and total number of grains had shown a positive direct effect with single plant yield. Days to 50% flowering, panicle weight, total numbers of grains had a positive significant and direct contribution towards yield improvement. Therefore, these traits are given more weightage while selecting the genotypes, for further utilization in crop improvement programmes.