Definition of Selection Criterion in a Subset of 3k Panel of Rice using Correlation and Path Coefficient Analysis

Abstract

Aims: Examining the genetic variability and the relationships between yield and its contributing traits in rice genotypes can enhance the potential for identifying superior lines capable of meeting the growing need for higher grain production and nutritional value. This study focused on assessing the correlation and path coefficients among rice germplasm lines to identify effective selection indicators that could support the development of high-yielding varieties. Study Design:  The subset of 3k Panel was evaluated in augmented design with ten blocks. Methodology: A total of 200 rice germplasm lines belong to 3K RGP along with five checks (Swarna sub-1, Sahyadri Jalamukthi, Sahyadri Kempumukthi, Jyothi and Sahyadri Jyothi) were evaluated for ten yield and yield related traits at ZAHRS Shivamogga, Karnataka, during summer 2024 and AHRS Kathalagere, Davanagere, Karnataka during Kharif 2024. The matrix of phenotypic correlations was estimated and analyzed into direct and indirect effects through path coefficient analysis. Results: Single plant yield was positively associated with number of productive tillers (r = 0.57***), number of tillers per plant (r = 0.57***), thousand grain weight ((r = 0.47**), number of spikelets per plant (r = –0.42***), spikelet fertility (r = –0.42***) and panicle length (r = 0.33***). A significant negative correlation was observed between single plant yield and plant height (r = -0.22**). Path coefficient analysis revealed that strong positive direct effect on single plant yield by number of tillers (0.51), panicle length (0.247), thousand grain weight (0.239) and spikelet fertility (0.155). Conclusion: Overall, these findings indicate that the positively significant association of the traits with yield, and their direct and indirect effects helps in making selection criterion to be used for selection of superior germplasm lines for further crop improvement.