Abstract
Previously, we investigated seedling emergence and establishment of direct-seeded rice under different air temperature and daily temperature range conditions using pregerminated seeds. Our results showed that the influence of daily temperature range after seeding was greater under low than under high temperature conditions. Furthermore, the growth under low temperature conditions after seeding was promoted when the daily temperature range was wider. In the present study, we investigated seedling emergence and establishment of direct-seeded rice grown under different daily temperature ranges in low temperature conditions using calcium peroxide-coated, iron-coated, and non-coated seeds in an incubator. Calcium peroxide-coated seeds had the highest seedling emergence and establishment rates that were least influenced by the daily temperature range. In all types of seeds, the growth under low temperature conditions after seeding was better under a wider daily temperature range condition. Furthermore, seedling emergence rate estimated by the Arrhenius equation well simulated the measured value.
