Effect of Alien Cytoplasm on Combining Ability for Earliness and Seed Yield in Sunflower under Irrigation and Drought Stress.

Nine CMS analogues from different cytoplasmic sources and their common maintainer were crossed with four perfect restorers from PET-1 source to develop of 40 sunflower hybrids. The experiment was conducted during spring season 2011 and 2012 two years continuously, under two different water environments, normal irrigated and water stress environment, where irrigation was stopped after the anthesis. The analysis of variance revealed significant differences among the sources for day to flowering, days to maturity and seed yield under both the environments, both the years and pooled over the years. The variance due to GCA and SCA showed that gene action was additive for maturity whereas, non-additive genetic effect was observed for days to flowering and seed yield under both the environments. The CMS analogues E002-91A (H. annuus), PKU-2A (H. annuus), and ARG-3A (H. argophyllus) were recorded as good combiner for early flowering in both the environments. The CMS analogs E002-91A and ARG-3A were observed good combiners for early flowering, early maturity and high seed yield, whereas, NC-41B from conventional CMS source H. petiolaris (PET-1) was recorded good combiner for late flower and early maturity and poor combiner for seed yield under both the environments. Among testers P69R was recorded good combiner for late flowering under normal water environment while, in water stress it was good combiner for early flowering but it was not good for seed yield. RCR-8297 was recorded for good combiner for late maturity and high seed yield under both the environments. The SCA estimates were highest in cross E002-91A× RCR-8297 and PKU-2A × P124R and ARG-6A × RCR-8297 for early flowering and early maturity under both the environments. These new cytoplasmic male sterility sources can be substitute of the classical (PET-1) source with added advantage for early maturing and high yielding. [ABSTRACT FROM AUTHOR]