Correlation and Path Coefficient Studies in Elite Medium-Duration Rice Genotypes under Saline Conditions
K. N. Rao
*
ANGRAU-Agricultural Research Station, Machilipatnam-521002, India.
M. G. Rani
ANGRAU-Regional Agricultural Research Station, Maruteru-534122, India.
V. Vinutna
ANGRAU-Agricultural Research Station, Machilipatnam-521002, India.
V. Sailaja
Lam Farm, Guntur-522034, India.
*Author to whom correspondence should be addressed.
Abstract
Improving grain yield under coastal soil salinity requires identifying rice genotypes with favorable agronomic performance and informative yield-associated traits. This study evaluated correlations and path coefficients among yield components and salinity-response traits in elite medium-duration rice genotypes. Thirty-eight entries were evaluated during Kharif 2024 at the Agricultural Research Station, Machilipatnam, Andhra Pradesh, using an alpha-lattice design with two replications. Seedlings were transplanted into naturally saline soil, where recorded electrical conductivity ranged from 7.3 to 7.8 dS m⁻¹ across crop growth stages. Eleven traits, including grain yield, plant survival, ear-bearing tillers, spikelet fertility and salinity scores, were assessed. Analysis of variance indicated significant differences among genotypes for all evaluated traits (P < 0.01). Mean grain yield was 5,126.28 kg ha⁻¹, with observed values ranging from 3,689.88 to 6,724.87 kg ha⁻¹. At both phenotypic and genotypic levels, grain yield was positively associated with plant survival, plant height and ear-bearing tillers per square meter, and negatively associated with salinity scores at the seedling and reproductive stages. Path analysis indicated positive direct effects of plant survival, plant height, ear-bearing tillers, days to maturity and spikelet fertility on grain yield. Three lines, MCM 253-17-1-1-1, MCM 253-14-2-2-2 and MCM 253-1-4-1-1, showed favorable yield and salinity-tolerance performance relative to the checks. These findings identify potentially useful selection traits and promising lines for further evaluation under coastal saline conditions.
Keywords: Rice genotypes, coastal soil salinity, medium-duration rice, grain yield, correlation coefficient, path coefficient analysis, salt tolerance