Genetic variability studies in new versions of sunflower (Helianthus annuus L.)

Genetic variability in newly developed 79 versions of Morden and EC-68415 varieties of sunflower was studied for nine characters. High range of variability was observed for days to maturity, plant height, test weight and seed yield per plant. Maximum genotypic coefficient of variation was observed for seed yield per plant followed by hull content. The estimates of heritability and genetic advance expressed as percent of mean was high for plant height followed by hull content indicating additive gene control. The screening of new versions against downy mildew disease reaction under artificial epiphytotic condition showed that, 20 new versions showed ‘0’ disease reaction. The highly resistant versions like LDMRM-11-60, LDMRM-111-2b-62, LDMRM IV-5-1-18, LDMRM-V-12-1-46 and LDMRM-VII-5-38 recorded high seed yield, whereas disease reaction was resistant with 13 new versions (1–10%). The estimates of relative self incompatibility in new versions revealed that the seed set in open pollination condition was more, compared to controlled pollination. The new version LDMRM-II-1-69-35 was highly self incompatible. The versions, LDMRM11–60 and LDMRM-IV-3-1-55 showed highest seed set under controlled condition to the extent of 26.40 g and 39.90 g respectively and are said to be with high self compatibility level.