Appropriate water management for rice cultivation using non-coated seeds directly seeded with a puddling seeder

Abstract

We examined the effects of water management on seedling establishment and yield of lodging-tolerant rice cultivar, ‘Moeminori’. The non-coated seeds were directly seeded using a puddling seeder. Field experiments were conducted in a paddy field in the Tohoku Agricultural Research Center (NARC), in Akita Prefecture, Japan, from 2013 to 2017. We tested four water management systems: flooding, flooding-drainage (7-day flooding, followed by 5-to 7-day drainage), short-term drainage (7-to 8-day drainage), and long-term drainage (12-to 13-day drainage). Seedling establishment was better with the long-term drainage treatment than the flooding and flooding-drainage treatments. Differences in growth, yield, and grain quality between the treatments were negligible. Lodging was higher with the flooding treatment than the short-term drainage treatment. On-farm trials were conducted at two sites in Akita Prefecture from 2014 to 2016. We tested two water management systems: flooding-drainage (8-day flooding, followed by 3-to 12-day drainage) and drainage (8 to 15 days). Seedling establishment tended to be better for the drainage treatment, when the seeding depth was the same. Differences in growth, yield, and grain quality between the treatments were negligible. This method was as practical as direct seeding of iron-coated seeds, which is conventionally used for seedling establishment. Drainage for about 12 days was therefore appropriate for this cultivation method.