Pollination behavior determines the extent of self-incompatibility in pansy (Viola× wittrockiana Gams.)

The study examined the impact of pollination methods at different timings on various inbred genotypes of pansy (Viola × wittrockiana Gams.) over 2 years in India’s sub-tropical conditions. Four pollination methods were assessed: open pollination, natural self-pollination, hand self-pollination and sib-mating, at two pollination timings: 8–9 a.m. and 9–10 a.m., across seven pansy genotypes. Results showed that capsule and seed set were significantly influenced by both genotype, pollination methods and timing. Natural self-pollination yielded the lowest capsule set and seed yield, with no capsules in some large-flowering genotypes, indicating complete self-incompatibility. Open pollination had the highest results, with an average capsule set of 74.84 % and seed yield of 0.54 g/plant, confirming cross-compatibility in all genotypes. Among controlled methods, hand self-pollination at 8–9 a.m. was most effective, achieving 60.87 % capsule set and 0.48 g/plant seed yield, compared to pollination at 9–10 a.m. (47.86 %; 0.39 g/plant). Punjab Sunaina and Punjab Neelima were the top performers, with capsule sets of 78.56 % and 75.89 %, and seed yields of 0.98 g/plant and 0.96 g/plant, respectively. Punjab Sunaina excelled in open pollination (95.56% capsule set) and hand self-pollination at 8–9 a.m. (90.56 %). The study concluded that all genotypes are cross-compatible but self-incompatible. Open pollination is the best method for capsule and seed set, while hand self-pollination at 8–9 a.m. is optimal for maintaining pure inbred lines in self-incompatible genotypes.