Identification of Autogamous and Self-Fertile Lines in Sunflower (Helianthus annuus L.) Over Seasons

Abstract

This study aims to assess the autogamy and self-fertility percentage in sunflower (Helianthus annuus L.) across two distinct cropping seasons. Sunflower possesses self-incompatibility which can be overcome by exploring alternate pollination methods. Autogamy and self-fertility are two desirable traits of sunflowers that play an important role in reproductive success and yield stability. Through the examination of 46 genotypes, the research aims to determine the effects of seasonal variations on seed set, autogamy, and self-fertility across different sunflower genotypes during the Kharif and Rabi seasons. The study compared three modes of pollination: self-pollination (SP), self-pollination plus manual (S+M) pollination, and open pollination (OP). Results indicated that the Rabi season favoured a higher seed set and better seed filling compared to the Kharif season. The study revealed that the Rabi season’s cooler temperatures, higher humidity, and reduced solar radiation positively influenced seed yield and quality. In contrast, Kharif season conditions, particularly the monsoon, led to reduced seed yield and fewer filled seeds due to factors like higher pollen movement and lower humidity inside pollination bags. The autogamy and self-fertility percentages during Rabi were higher at 79.01 percent and 85.01 percent, respectively. Genotypes PB-892, EC-198072, and PB-1444 showed the highest seed set under S+M pollination during Kharif, while CMS-107B, PB-1212, and CMS-47B excelled in SP. Across both seasons, EC-198078, EC-178168, and GMU-770 were identified as highly self-fertile, making them valuable for developing self-fertile hybrids and enhancing population development.