AGRO-MORPHOLOGICAL CHARACTERIZATION AND GENETIC DIVERSITY ASSESSMENT OF NINETEEN BRRI-RELEASED RICE VARIETIES

Abstract

Knowledge on genetically determined several growth parameters including morpho- physiological and developmental parameters are essential for rice breeding programs. Genetic divergence helps in the development of superior recombinants, which is prerequisite in any crop improvement program. The aim of the present study was to characterize 19 rice varieties based on agro-morphological descriptors and genetic diversity. The experiment was conducted at Bangladesh Rice Research Institute farm, Gopalganj, using a randomized complete block design with three replications. Both the qualitative and quantitative agro-morphological traits were diversified. The observed variations in the qualitative data were primarily accounted for by the blade pubescence, anthocyanin color of the leaf sheath, lemma-palea color, grain tip color, and awning. The top five axes of PCA contributed 81.04% of the total variation. The varieties were divided into five groups based on the cluster. With six genotypes, Cluster IV was the largest group, whereas Cluster I was the lowest with just one genotype. Cluster IV had the greatest intra-cluster distance, whereas clusters IV and I had the greatest inter-cluster distances. Contrarily, cluster IV had the highest cluster means for most of the quantitative characteristics noticed. Once more, grain length was the trait that contributed most to divergence. While considering results from genetic distance, the varieties under cluster IV (BRRI dhan29, BRRI dhan89, BRRI dhan92 BRRI dhan97, BRRI hybrid dhan3, BRRI hybrid dhan5) might be selected for additional breeding after taking the results of the genetic distance into consideration.