Genetic divergence of twenty eight Thermo-sensitive Genic Male Sterile lines in rice was studied for twelve characteristics. Among the traits studied, panicle exertion contributed the most for the genetic diversity of TGMS lines followed by spikelet fertility and stigma length. The TGMS lines were grouped into twelve clusters, of which cluster VII with five genotypes was the largest and cluster XII was the smallest with one genotype. The intra cluster distance ranged from 0.00 (cluster XII) to 15.51 (cluster VII). The inter cluster distance was found to be the highest between clusters III and XII (28.16). When the cluster mean was compared for twelve traits observed, cluster II and X expressed low pollen fertility of less than 1.0 per cent and spikelet fertility of less than 4.0 per cent. The clusters I, VI and XII recorded the pollen fertility of less than 90 per cent, whereas the clusters VIII, III and IX expressed pollen fertility of 80 per cent and above. The entries in cluster X had more than 80% of panicle exertion with more than 20o as angle of glume opening. The stigma length was high with moderate number of spikelets per panicle and panicle length. Since the TGMS lines in cluster X had more number of desirable traits, they can be effectively utilized for heterosis breeding in rice.
diversity, rice, TGMS lines
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