Morphological variability and genetic diversity of Aman rice germplasm of Bangladesh cultivated in Mymensingh region

Thirty-one Aman rice germplasm were evaluated to assess their morphological variability and genetic diversity considering ten quantitative and thirty one qualitative traits at the field experimental plot of Bangladesh Institute of Nuclear Agriculture, Mymensingh, following randomized complete block design. The germplasm showed significant differences for all the studied traits. The highest grain yield/plant was recorded in Sentu-16 whereas the lowest was found in Gaindha. The genotypic coefficient of variation (GCV) was lower than those of the corresponding phenotypic coefficient of variation (PCV) for all the traits. High PCV and GCV along with heritability, genetic advance (GA) and GA in percentage of mean were recorded for number of filled grains/panicle and number of unfilled grains/panicle. Grain yield/plant had positively significant correlation with plant height, number of total tillers/hill, number of effective tillers/hill, number of filled grains/panicle and thousand grain weight. Path co-efficient analysis suggested that grain yield/plant had positive direct effect in association with days to fifty percent flowering, number of effective tillers/hill, panicle length, number of filled grains/panicle and thousand grain weight. Principal component analysis revealed that the first three components accounted for 79.57% of cumulative variance. Cluster analyses were revealed that the studied rice germplasm organized into five clusters based on D2 values where maximum intercluster distance was observed between cluster II and V. Qualitative characterization by distinctness, uniformity and stability test revealed that a wide range of variation was observed among the genotypes. Therefore, this study would be useful for breeders to choose and identify the revival and preservation of beneficial genes for crop improvement.