**3.1 Materials and methods**

The study was conducted at the same location in Experiment 1. We used six rice cultivars in this study. The nursery growing and transplanting methods used were similar to those in Experiment 1. Table 6 shows the seeding dates and dates for measuring panicle temperature. The planting density was 22.2 hills m−2. The area of each plot was 12.8 m2. A basal dressing of 4.0 g m−2 of N, 4.9 g m−2 of P2O5, and 4.3 g m−2 of K2O was applied. Top dressing was not used. Culture methods such as irrigation and pesticide used followed the standard local practices for rice production in Shimane Prefecture.


Table 5. Seeding dates and measurement dates for six *O. sativa* cultivars in Experiment 2.
