GENETIC VARIABILITY, CORRELATION AND PATH ANALYSIS OF RICE GENOTYPES IN RAINFED CONDITION AT LAMJUNG, NEPAL

Abstract

An experiment on eleven rice genotypes was designed at field of Institute of Agriculture and Animal Science, Lamjung, under randomized complete block design with three replications from June-October, 2018 to study genetic variability and character association. Analysis of variance showed significant difference among the genotypes for all the characters studied except for grain yield and fertility percent which indicates the existence of sufficient genetic variability and potential for selection and further improvement. Grain yield was significantly positively correlated with panicle length while positively and non-significantly correlated with days of flowering, leaf area and straw yield except for plant height, SPAD60, fertility percent, thousand grain weight and effective tillers. Leaf area had maximum positive direct effect on grain yield followed by panicle length, thousand grain weight and effective tillers which indicates help for selection and improvement of rice genotypes. The higher value of correlation between panicle length and grain yield is due to the direct effect of panicle length which exhibit true relationship between them. The variability study showed that there was high genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) for thousand grain weight. High heritability estimates coupled with high genetic advance as per percentage of mean (GAM) was found for thousand grain weight, days of flowering, leaf area and effective tillers which indicate the control of additive gene of action and a greater scope of selection for crop improvement.

Keywords

• Genetic advance
• genotypic coefficient of variation
• heritability
• phenotypic coefficient