Genetic diversity studies of quality characters of promising rice varieties

Forty-two promising rice varieties of southern India evaluated for physico-chemical and cooking characters to study the diversity pattern among the genotypes were grouped into seven clusters. Maximum 16 genotypes were grouped in cluster I followed by 12 in cluster III and 10 in cluster II. The clusters IV, V, VI and VII are represented by single genotypes, namely, Erramallelu, Mahsuri, Cottondora Sannalu and Vajram, respectively, indicating high degree of heterogeneity among the genotypes. The highest intra-cluster distance was observed in cluster III (D= 13.88) followed by cluster II (D=10.97), cluster I (D=8.43). The coefficient of variation was highest in water uptake (20.76) and lowest coefficient of variation was reported in hulling percentage (2.24). The cluster means were highest for cluster V for head rice recovery and cluster VI for length-breadth ratio. The cluster VII exhibited high mean value for volume expansion ratio and elongation ratio. The head rice recovery had maximum contribution value (15.80) followed by water uptake (13.71), and lowest value was observed in milling per cent (3.25). Hulling per cent, head rice recovery, alkali spreading value, volume expansion ratio and water uptake together contributed more than 50% towards total divergence. Hence, these characters should be considered during hybridization programme.