Adaptation activity
The quality of unmilled rice has recently been on the decline, which is considered to be a consequence of global warming. This has become a problem nationwide, and in Hiroshima Prefecture, the Hinohikari variety, which is grown at altitudes up to 100m above sea level, has been particularly affected. The more heat-stress resilient Koinoyokan variety is therefore being promoted as a possible alternative, which has similar growth cycle characteristics to hinohikari, and should be easy for farmers to switch to.
Koinoyokan has long top leaves that stand upright, which aids in photosynthesis, and the plant is relatively short with a stiff stalk that resist bending. In addition, the appearance of chalky immature grain is limited, even if ripening occurs due to particularly warm temperatures, and the rice retains its quality and flavor. The cultivation of Koinoyokan will be gradually expanded in southern parts of Hiroshima in order to replace Hinohikari.