Maintaining Onion Seed Quality during Storage Through Seed Priming

Abstract

Background: Seed is an important component and the quality seed plays a crucial role in agricultural production as well as in the national economy. Availability of viable and vigorous seeds at the planting time is important. Onion seeds have a short life span among the vegetable crops and lose viability rapidly after harvest. The main reason for the low quality of onion seeds includes a long flowering period resulting in different stages of seed maturity in the umbel, very fast reduction of viability if stored in suboptimal conditions and seed infestation with fungi. Seed priming is a widely used technique to enhance seed performance during storage. Methods: The seed was primed with Neem leaf powder (100 g/kg) after hydration and dehydration, hydration with KH2PO4 (2.0%), KNO3 (1.0%), K2SO4 (1.0%) and Captan (N-trichloromethylthio-4-cyclohexane-1,2-dicarboximide) at 2.5 g/kg and stored in polyethylene (100µ) bags under ambient conditions. After each treatment, seeds were dried back to their original moisture content under shade. Result: The results revealed that different priming treatments had a significant effect on germination percentage, seedling length and vigour index-I except for moisture percentage in both the years. The maximum germination (74.1 and 71.2%) was observed in seeds treated with Captan (2.5 g/kg) followed by Neem leaf powder 100 g/kg seed (71.1 and 69.72%) during 2014-15 and 2015-16, respectively. The onion seeds primed with KH2PO4 (2.0%), KNO3 (1.0%) and K2SO4 (1.0%) had an adverse effect on seed germination. The germination decreased significantly with the increase in the storage period. The maximum seedling emergence (60.0%) was observed from the seed primed with Captan (2.5 g/kg) followed by Neem leaf powder 100 g/kg seed (56.1%).