Evaluation of Genetic Variability, Correlation and Path Analysis for Yield and Yield Components in Local Rice Land Races of Tamil Nadu, India
Konne Deepika
*
Department of Genetics and Plant Breeding, Agricultural College, Polasa, PJTAU, Jagital, 505529, Telangana, India.
R. Manimaran
Department of Genetics and Plant Breeding, Tamil Nadu Rice Research Institute, Aduthurai-612101, Tamil Nadu, India.
R. Pushpa
Department of Genetics and Plant Breeding, Tamil Nadu Rice Research Institute, Aduthurai-612101, Tamil Nadu, India.
K. Sathiya Bama
Department of Soil Science & Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore-641003, India.
C. Umamageswari
Department of Agronomy, Agricultural College and Research Institute, Chettinad-630102, India.
R. Suresh
Department of Rice, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore-641003, India.
*Author to whom correspondence should be addressed.
Abstract
Traditional rice landraces of Tamil Nadu constitute an important reservoir of genetic diversity for yield and adaptive traits, offering valuable resources for rice improvement programmes. Assessing genetic variability, trait associations, and the direct and indirect effects of yield-contributing characters is essential for identifying effective selection criteria for the development of high-yielding rice cultivars.
The present investigation was carried out of assess the extent of genetic variability, association among traits and direct and indirect effects of yield contributing characters in traditional rice (Oryza sativa L.) genotypes. A total of 50 traditional rice genotypes were evaluated for thirteen quantitative characters. Analysis of variability revealed high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) for total number of grains per panicle, number of productive tillers per hill and flag leaf length indicating the existence of substantial variability among the genotypes. High heritability accompanied by high genetic advance as a percentage of the mean was recorded for the number of productive tillers per hill, total number of grains per panicle, filled grains per panicle, and unfilled grains per panicle, indicating the predominance of additive gene action in the inheritance of these traits. Such findings suggest that these characters may respond effectively to direct selection in breeding programmes.
Correlation analysis further demonstrated that single plant yield exhibited a significant and positive association with the number of productive tillers per hill, plant height, panicle weight, number of branches per panicle, filled grains per panicle, and total number of grains per panicle. These relationships highlight the importance of these yield-contributing traits in determining overall productivity.
Moreover, path coefficient analysis revealed that total number of grains per panicle, filled grains per panicle, and number of productive tillers per hill exerted strong positive direct effects on single plant yield. The results therefore emphasise that these traits constitute reliable and effective selection indices for the improvement of grain yield in traditional rice genotypes.
Keywords: Variability, correlation, path analysis, rice landraces