Assessment of genetic variability, correlation, and path analysis studies in Bangladeshi local rice (Oryza sativa L.) cultivars
摘要
Rice yield improvement is constrained by the complex genetic control of yield and its component traits, along with limited understanding of their interrelationships in local germplasm. Therefore, it is essential to evaluate genetic variability and quantify trait associations to identify key determinants for effective selection in breeding programs. The goal of this study was to determine genetic variability, nature and extent of phenotypic and genotypic connections between yield and its component traits, as well as their direct and indirect effects on grain yield in rice. Six genotypes were studied to see how efficient they were in terms of yield and yield components. The correlation coefficient and path association were used to determine the degree (strength) and direction of the relationship between two or more variables, as well as to identify the traits that have yield influencing roles. Flag leaf length, panicle length, 100 grain weight, primary rachis number, secondary rachis number, and culm length had strong heritability and high to moderate genetic improvement as a percentage of mean. Grain yield was significantly and positively associated with three factors involving number of panicles per plant, number of tillers per hill, and grain length at both genotypic and phenotypic levels according to the correlation coefficient between seed yield per plant and other quantitative imposing to yield. Panicle number, flag leaf width, panicle length, grain length, grain width, secondary rachis number, and culm length showed a direct positive effect on seed yield per hill at the genotypic level. According to the correlation and path analysis, the most vital traits that directly associated with seed yield per hill were panicle number, flag leaf width, panicle length, grain length, grain breadth, secondary rachis number, and culm length. As a result, a genotype with a constant quality of these characteristics might be chosen from current genotypes or used to increase rice yield genetically.