title: Natural diversity of seed α-tocopherol ratio in wild soybean (Glycine soja) germplasm collection.
abstract: Alpha-tocopherol is one of four tocopherol isoforms and has the highest vitamin E activity in humans. Most cultivated soybean seeds contain γ-tocopherol as the predominant form, and the ratio of α-tocopherol content to total tocopherol content (α-tocopherol ratio) is <10%. Three soybean accessions from Eastern Europe have α-tocopherol ratios of >20%. This higher content is likely due to mutations in the promoter region of theγ-tocopherol methytransferase-3(γ-TMT3) gene. We surveyed a wild soybean germplasm collection and detected 16 accessions with stable seed α-tocopherol ratios of >20% under different growth conditions. The α-tocopherol ratios were greatly reduced when the plants were grown under cool temperatures during seed maturation, but increased to varying degrees at higher temperatures. Sequence analysis of theγ-TMT3promoter of 11 of the accessions identified four haplotypes, one of which corresponded to that of cultivars with higher contents. These wild accessions can thus serve as novel donors for breeding cultivars with high α-tocopherol ratios and for better understanding the genetic basis of α-tocopherol synthesis in soybean.
authors: Genotyping Services Laboratory, Plant Breeding Division, International Rice Research Institute , Los Baños, Laguna 4031 , The Philippines.
authors: Maria Stefanie
authors: MS
authors: Dwiyanti
authors: Laboratory of Plant Genetics and Evolution, Research Faculty of Agriculture, Hokkaido University , Kita 9 Nishi 9, Kita, Sapporo, Hokkaido 060-8589 , Japan.
authors: Shouhei
authors: S
authors: Maruyama
authors: Laboratory of Plant Genetics and Evolution, Research Faculty of Agriculture, Hokkaido University , Kita 9 Nishi 9, Kita, Sapporo, Hokkaido 060-8589 , Japan.
authors: Mari
authors: M
authors: Hirono
authors: Laboratory of Plant Genetics and Evolution, Research Faculty of Agriculture, Hokkaido University , Kita 9 Nishi 9, Kita, Sapporo, Hokkaido 060-8589 , Japan.
authors: Masako
authors: M
authors: Sato
authors: Department of Biotechnology, College of Applied Life Science, Yeungnan University , Gyeongsan, 38541 , South Korea.
authors: Euiho
authors: E
authors: Park
authors: Grassland and Forages Division, National Institute of Animal Science , Chungnam, 330-801 , South Korea.
authors: Sei Hyung
authors: SH
authors: Yoon
authors: Laboratory of Plant Genetics and Evolution, Research Faculty of Agriculture, Hokkaido University , Kita 9 Nishi 9, Kita, Sapporo, Hokkaido 060-8589 , Japan.
authors: Tetsuya
authors: T
authors: Yamada
authors: Laboratory of Plant Genetics and Evolution, Research Faculty of Agriculture, Hokkaido University , Kita 9 Nishi 9, Kita, Sapporo, Hokkaido 060-8589 , Japan.
authors: Jun
authors: J
authors: Abe
keywords: Glycine max; functional food; genetic diversity; nutraceutical; soybean; vitamin E; wild germplasm