Priming with Seeding Mixture to Improve Emergence from Okra Seeds at Non-High-Temperature

Abstract

A study was conducted to develop a simple priming method to improve seedling emergence of okra seeds in non-high-temperature seasons using a seeding mixture as a moisture-conditioning agent. ‘Tokyo Gokaku’ seeds were primed in bottles at 15 to 30°C for 1 to 4 days with seeding mixtures having moisture contents ranging from 35 to 55%. After treatment, seeds were sown in containers at 20°C. Seedling emergence was markedly promoted under the conditions of 30°C/1d/45% moisture: the percentage emergence at 8 days after sowing was 94%, whereas emergence was 53% in the non-treated control. The seeds sown directly in the field in May after priming (30°C/1d/45% moisture) emerged earlier and grew into seedlings with a more uniform top fresh weight compared with the non-treated seeds. The seeds kept at room temperature for several days after priming (30°C/1d/45% moisture) and sown in the field in May showed no differences in emergence compared with seeds sown just after priming. Priming in this study improved emergence, and the effects were maintained even in seeds that were temporarily stored after treatment to simulate postponed sowing.