Abstract
Genetic divergence of 48 IRRI developed F1 rice hybrids were studied through Mahalanobis D2 and principal component analysis for ten characters in Gazipur and Pabna district during dry season 2012-13. Among 48 genotypes, cluster analysis resulted in five clusters following Wards method. During dry season for both regions, cluster I incorporated the highest number of genotypes. Significant differences among the genotypes but non-significant differences among replications were noticed for most of the parameters under study. The inter-cluster distance was larger than intra-cluster distance suggesting wider diversity among the genotypes. In Gazipur, the maximum inter-cluster D2 value was recorded between cluster III and V (6.69) and the minimum between cluster II and IV (0.69). The intra-cluster distance was maximum in cluster IV (3.60) and minimum in cluster I (0.33). In Pabna, maximum inter-cluster distance was exhibited between cluster IV and II (16.43) but minimum between cluster II and III (3.98). Maximum intra-cluster distance (4.40) was recorded in cluster IV whereas minimum in cluster I (0.83). Based on positive value of vector 1 and vector 2, panicle number m-2, spikelet fertility (%) and 1000-grain wt. (g) had maximum contribution towards genetic divergence among the characters studied. Cluster means indicated considerable differences in the mean values of different parameters. The highest cluster means for panicle weight (g), spikelet fertility (%), 1000 grain wt. (g) and grain yield (kg ha-1) were derived from cluster IV. Therefore, more prominence should be given to the lines under cluster IV that having genetic potentiality to contribute better for yield maximization of hybrid rice.
Highlights
World population has been increasing day by day
The present study was, focused on identification of promising hybrids among 48 International Rice Research Institute (IRRI) developed hybrid rice lines based on its performance in contribution to genetic divergence under two different agro-ecological zones of Bangladesh and an attempt was made to classify and understand the nature and magnitude of genetic diversity
An on farm trial was established with 48 F1 rice hybrids from IRRI with two popular BRAC hybrids Aloran, Shakti and a popular modern inbred variety BRRI dhan28 during dry season 2012 in BRAC Agricultural Research and Development Centre (BARDC), Gazipur and Dashuria Seed Farm, Pabna
Summary
World population has been increasing day by day. But population growth rate of Bangladesh is much higher than world growth rate. National rice production increased 253% from 1960 to 2009 (14.52 to 51.33 million ton) with average annual growth rate of 2.61% in Bangladesh. Peng et al (2003) mentioned that the average yield of F1 hybrid rice was 4% higher than that of indica inbred in the 1999 dry season. In Bangladesh, hybrid rice gains positive response in boro season (Haque and Biswas, 2011). Hybrid Rice Research and Development Consortium (HRDC) was formed in 2008 at International Rice Research Institute (IRRI) with the aim of accelerating the adoption of the technology. The present study was, focused on identification of promising hybrids among 48 IRRI developed hybrid rice lines based on its performance in contribution to genetic divergence under two different agro-ecological zones of Bangladesh and an attempt was made to classify and understand the nature and magnitude of genetic diversity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
