Iron toxicity occurs in many rice-growing regions in Asia and Africa and significantly reduces rice yields, so there is a need to improve tolerance to this stress. However, the key genes and physiological factors for tolerance have not yet been identified, and a search for key factors is needed. Based on a two-year study using genetically diverse rice lines in iron toxic fields in Madagascar, JIRCAS has shown that iron toxicity tolerant lines have different mechanisms depending on the growth stage and that iron toxicity tolerance is supported by more complex mechanisms than previously recognized. The study also demonstrated that evaluation of iron toxicity tolerance should be carried out at all stages in the field, and suggests that iron toxicity tolerance can be improved by breeding using parental lines with superior specific physiological functions.

Tocopherol is a fat-soluble antioxidant known as vitamin E. It has physiological functions in the prevention of lifestyle-related diseases such as cancer and atherosclerosis, as well as cardiovascular disease. Among the tocopherols, α-tocopherol has the highest vitamin E activity. However, the α-tocopherol content in soy is low, which limits the exploitation of the functional properties of soy. JIRCAS was able to identify the DNA regions and candidate genes that regulate the tocopherol biosynthetic pathway in soy. Modification of the tocopherol biosynthetic pathway may lead to the development of soybean with higher α-tocopherol content.