Seed invigoration treatments in different seed sizes of sunflower (Helianthus annuus L.) for maintenance of vigour, viability and yield potential

Pre-storage dry treatment of freshly harvested (high-vigour) sunflower (Helianthus annuus L.) seeds in different seed sizes (viz. composite, large, medium and small) with red chilli powder (@ 1 g/kg of seed) and bleaching powder (@ 2g/kg of seed) significantly slowed down seed deterioration under natural ageing conditions and increased field performance and productivity along with reduced leakage of electrolytes, lower volatile aldehyde production with higher dehydrogenase enzyme activity over their respective untreated control. Among the seed sizes, large seeds showed higher post-storage germinability as well as field performance and productivity than the other categories of seeds. Interaction effects were non-significant which indicated that the treatment effects are independent of seed sizes. On the basis of the present investigation, pre-storage dry treatments in large sized seeds with red chilli powder and bleaching powder may be suggested for improved germinability and yield potential of stored high-vigour sunflower seeds.