Fig. 1.

Relationship between days to heading (DTH) in a photoperiod-controlled phytotron (high temperature, short day-length) and under field conditions for the 46 accessions. The diagonal line represents y = x. Photoperiod-controlled phytotron: 35°C during the 10-h-light period and 28°C during the 14-h-dark period. The CO₂ concentration was not controlled. Field conditions: an experimental paddy field in Yawara, Tsukubamirai, Ibaraki, Japan (36°01′N, 140°02′E). The seeds were sown on 25 April and transplanted on 26 May 2011.