Assessment of variability of floral and yield traits: ii. maintainer lines of rice

Abstract

Abstract : Eleven maintainer lines of rice (Oryza sativa L.) were evaluated to study the genetic variability, character association and path coefficient analysis of floral as well as yield traits at the experimental farm, Department of Genetics and Plant Breeding, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur during July 2002 to December 2002. The maintainer lines exhibited a wide range of variability for all the traits except pollen diameter. The range of variation was much pronounced for all the traits studied. Minimum differences between genotypic coefficient of variation and phenotypic coefficient of variation were observed for most of the traits indicating little environmental influence for the traits. High heritability as well as high genetic advance and genetic advance in percent of mean were observed for anther length, pollen sterility, duration of anthesis, percent spikelet sterility, panicle length and grain yield per hill indicated that these traits could be improved through selection and had additive gene action. Anther length, duration of anthesis, panicles per hill and panicle length had a high degree of significant positive association with grain yield per hill indicated that these characters have the major contribution towards the grain yield per hill. Anther length and panicle length are identified as the most important floral and yield related traits due to their high to moderate genotypic and phenotypic variances, minimum difference of genotypic coefficient of variation and phenotypic coefficient of variation, high Heritibility in broad sense with high genetic advance and genetic advance in percent of mean, significant positive correlation and high positive direct effects. Direct selection on the basis of these two traits might be considered for the improvement of grain yield of maintainer lines.