2.1 Crop establishment
IR64, an Indica group cultivar, and a BC3-derived NIL
with IR64 genetic background, IR64+qEMF3 (Hirabayashi et al.,
2015), were used for all six experimental sites, which were located in
the temperate (Joetsu, Niigata, Japan), subtropical (Ishigaki, Okinawa,
Japan), and tropical (Nay Pyi Taw, Myanmar; Los BaƱos, Laguna,
Philippines; Coimbatore, Tamil Nadu, India; Subang, West Java,
Indonesia) regions across five countries (Table 1), following the local
rice cultivation practices (Table S1). Plants were grown in fields
during the summer/dry season (Table 1). Note that two staggered sowings
were employed in Nay Pyi Taw for 2017DS, 2018DS, and 2019DS to expose
rice plants to different temperatures at heading. 50% heading date was
recorded for each genotype in each trial to determine the
days-to-heading. Plant materials were kept healthy by spraying
agrochemicals, when required.