Genetic Divergence of Balam Rice (Oryza sativa L.) Germplasm of Bangladesh

Abstract

Forty genotypes of Balam rice germplasm of Bangladesh were studied for 17 morphophysicochemical characters at BRRI during 2009-11. The cluster analysis using Mahalanobis' D 2 statistics, grouped the genotypes into seven clusters, where no duplicate germplasm was found for the studied characters. The highest number of genotypes (8) was constellated into clusters I, III and V and the lowest (2) was in cluster IV. The intraand inter-cluster distances were maximum (1.17 and 21.16) in cluster VII and between clusters II and IV and minimum (0.27 and 2.23) in cluster IV and between clusters II and VII respectively. Based on the values of principal component score, the two-dimensional scatter diagram (Z1-Z2) also distributed the genotypes into seven groups. The genotype of cluster IV, produced the highest flag and penultimate leaf area (1136 cm 2 ), culm diameter (7.2 mm), days to maturity (152 days), primary and secondary branches per panicle (63), grain yield per panicle (4.9 g), 1000-grain weight (29.3 g), grain yield per hill (31.3 g), cooking time (19 min) and amylose content (24.1%). Similarly, the genotype of cluster I, produced the tallest plant (148 cm), maximum straw yield per hill (40.0 g) and protein content (9.6%), while the genotype of cluster VI, produced the highest panicle per plant (21) and the genotype of cluster III, produced the longest grain (8.8 mm). Therefore, it may be possible to obtain the highest mean values for the maximum studied characters, if the genotypes of cluster IV are crossed with the genotypes of cluster I, cluster III and cluster VI respectively. Besides, the canonical variate analysis showed that the grain length, cooking time, straw yield per hill, days to maturity, plant height and grain yield per panicle contributed maximum to the genetic divergence of the studied germplasms. Finally, the study revealed that the Balam rice germplasm can offer a diverse valuable gene reservoir to utilize in hybridization programmes for the improvement of Balam rice.

Phenotypic Characterization of Jhum Rice (Oryza sativa L.) Landraces Collected from Rangamati District in Bangladesh

“…The result exposed that the first five components in the PCA with Eigen values >1.0, contributed 81.14% of the total variations among the genotypes for 15 morphological characters. These results are in agreement with the findings of Ahmed et al (2015b). Fig.…”

“…The inter-cluster distances in all the clusters were higher than the intra-cluster distances suggesting wider genetic diversity among the genotype of different groups. The results were in agreement with Islam et al (2016), Akter et al (2016), Ahmed et al (2015b), Islam et al (2014) and Sohrabi et al (2012). Table 7 presents the cluster-mean values for all the 15 quantitative characters.…”

Agro-morphological Characterization and Genetic Diversity of Similar Named Aromatic Rice (Oryza sativa L.) Landraces of Bangladesh

“…On the other hand, the inter cluster distances in all the clusters were higher than the intra cluster distances suggesting wider genetic diversity among the landraces of different groups. The results were in agreement with Siddique et al (2013) and Ahmed et al (2015). Again, Islam et al (2016) reported intra and inter-cluster distance ranged from 0.61 to 1.27 and 3.71 to 16.12, respectively on aromatic and fine rice genotypes.…”

“…The cluster mean revealed that the crosses between the genotypes of cluster I with those of clusters II and IV would exhibit high heterosis for maximum good characters. Ahmed et al (2015) and Sohrabi et al (2012) earlier reported similar trend of conclusions on rice germplasm using D 2 statistic Table 8 presents contributions of the characters towards divergence. The canonical vector analysis revealed that the vectors (vector I and II) were positive for yield, grain breadth, days to flowering, days to maturity, culm diameter, ligule length.…”

Assessment of Genetic Diversity of Rice Genotypes for Submergence Tolerance in Rainfed Lowlands

“…Where, X 1 -Days to 50 per cent flowering X 6 -Number of spikelets per panicle X 11 -Harvest index (%) X 2 -Days to maturity X 7 -Number of filled grains per panicle X 12 -1000 grain weight (g) X 3 -Plant height (cm) X 8 -Panicle length (cm) X 13 -Absolute growth rate (mg/day/plant) X 4 -Number of tillers per plant X 9 -Grain yield per plant (g) X 5 -Number of productive tillers per plant X 10 -Straw yield per plant (g) The maximum inter cluster distance indicates the wider genetic diversity among the genotypes falling into the groups which can be utilized in hybridization programs while the minimum inter cluster distance indicates that the genotypes falling in such clusters are closely related and thus hybridization among such genotypes will not give any fruitful result. The greater distance between the two clusters indicates the wider genetic diversity between the genotypes (Ahmed et al, 2015). Hence it is desirable to select genotypes from the clusters showing high inter cluster distance coupled with high grain yield as parents in future breeding programs for developing varieties and hybrids with wider variability and desirable quality for submergence tolerance.…”