Fifty-one inbreds and three checks of sunflower were laid in a randomized complete block design following recommended package of practices. Correlation studies revealed that seed yield was positively and significantly associated with seed volume weight, hull percentage, percent autogamy, days to 50 percent flowering and oil yield. Oil content was positively associated with plant height, number of leaves per plant, seed volume weight, hull percentage, head diameter, percent autogamy, days to 50 percent flowering, 100-seed weight, seed yield and oil yield. Path coefficient analysis for seed yield at phenotypic level showed that the direct effect was maximum for oil yield followed by 100-seed weight. The maximum indirect effect for seed yield was minimum through oil yield, while it was through yield per plant for oil.

Genetic divergence of 51 inbreds and 3 checks of sunflower was assessed using the Mahalanobis D 2 statistics. Fifty-one sunflower inbreds plus three checks, GAUSUF-15, TNASUF-7 and TNAU-1, of diverse geographical origin, were grouped into eight clusters which were not related to their geographic origin. Stem girth and seed yield per plant contributed the most to the total genetic divergence. Maximum inter-cluster distance was observed between the inbreds grouped in clusters I and V containing five and twelve inbreds, respectively, while the intra-cluster distance ranged from 0 to 2306.05. Based on mean performance, genetic divergence and clustering pattern, few inbreds namely CMS-234B, 7-1-B, CMS-597B, CMS-852B, ARM-250B, ARM-245B, HAM-69, ARM-284B, ARM-247B and HAM-174 were considered as potentially important for further breeding programs.

Sunflower (Helianthus annuus L.) being a cross pollinated crop, genetic adulteration is a vested problem and varietal descriptions are cumbersome. In order to identify genotypes and to establish phylogenetic relationships an investigation was carried on sunflower hybrids/parental lines/varieties using isoenzyme variation. The data on six isoenzymes were analyzed using Popgene software (Yeh, 1997). Genotypes which were morphologically closely related were found to be unrelated at the biochemical level. Hybrid KBSH-42 could be distinguished from the rest of the hybrids for the absence of pgi-2 and pgi-3. Alleles g 6 pdh-l, me-1 and skdh-3 served as markers in distinguishing the genotypes. Thus the results obtained could be used in fingerprinting the genotypes.