Vol. 9, Issue 1 (2020)

Author(s):
K Rukmini Devi, V Venkanna, Y Hari, B Satish Chandra, N Lingaiah and K Rajendra Prasad

Abstract:
An experiment was conducted with 71 rice genotypes to assess the genetic diversity and variability by using Mahalanobis D² Statistical and principal component analysis. All genotypes exhibited a wide and significant variation for 21 traits. The cluster analysis indicated that 71 genotypes were grouped into eleven clusters and cluster 1 followed by cluster 11 consisted with 33 and 29 genotypes respectively and rest of the nine clusters contain one genotype each. The maximum inter cluster distance was recorded between clusters VIII (906.17) with cluster V followed by cluster VII (682.74) and cluster I and also between cluster V (657.43) and cluster11. The lowest inter cluster distance (70.66) was observed between cluster III and cluster IV. The intra cluster D²values ranged from zero (cluster XI, X, IX, VIII, VII, VI, V, IV, III) to 128.42 (cluster I). Cluster VIII recorded highest cluster mean for water uptake, alkali spreading value, while cluster IX showed highest cluster mean for grain yield/plant and effective tillers and second highest for kernel length, days to 50% flowering and panicle density. Milling percent head rice recovery Kernel length. length/breadth ratio, Kernel length after cooking and water uptake. Contribution of days to 50% flowering was highest towards genetic divergence (36.05) by taking 896 times ranked first followed by kernel length after cooking (23.9) by 593 times, water uptake (10.0)and kernel length(8.5).The PCA analysis showed that the first five principal components accounted for about 82.23% of the total variation and exhibited very high correlation among them. Phenotypic coefficient of variation was higher than genotypic coefficient of variation. The traits panicle density, filled seeds/panicle volume expansion ratio and yield per plant exhibited high phenotypic coefficient of variation (PCV) and genotypic coefficient of variation. High heritability coupled with high genetic advance as percent of mean was recorded for the characters panicle density (83.5; 62.7), filled grains/panicle (82.6; 60.5), test weight (93; 52.9) and water uptake (90.9, 51.1). The genotypes RCPR32-HHZ-5-DT-20-DT-3 and RGL 7011 having maximum genetic divergence with high mean values for desirable yield contributing characters and quality traits could be utilized in the breeding programmes.