2020 Volume 89 Issue 2 Pages 126-133
In 2017, intensely yellow-colored grains(YCG)occurred in seed production fields of two-rowed barley cultivar “Haruka-Nijo” in Fukuoka prefecture. Color characteristics of the kernels were different from those of discolored kernels, an important type of grain damage in hulled barley. The factors affecting the occurrence of YCG, and the effects of YCG on seed quality were unknown. To investigate the factors affecting the occurrence of YCG, the correlation between three grain color values(L* value: brightness, a* value: redness and b* value: yellowness)and weather conditions were investigated. As a result, the L* value decreased while both a* and b* values increased in grains subject to 2.5 mm rainfall from the maturation period to harvest. A similar trend for color change of grains was confirmed when detached ears, not subject to rainfall subsequent to ear emergence, were treated at high humidity for 2 days. Furthermore, there are indications that a* and b* values are likely to increase in “Haruka-Nijo” as compared to other popular cultivars in Fukuoka. Results of analyzing the relationship between grain color values and seed quality, i.e., germination rate, thousand grain weight, and seed dormancy, showed that YCG is not inferior to normal color grains. These results show that YCG in “Haruka-Nijo” occurs due to very limited rainfall from the maturation period to harvest, and does not affect seed quality.
