Biosystematics of Triticeae

Professors Chi Yen and Junliang Yang are botanists, crop geneticists, and breeders. They are famous in promoting the research of the systematics of Triticeae in the world and has made outstanding contributions to the study of Triticeae germplasm resources.

Professors Chi Yen and Junliang Yang revealed the transfer of cell nuclear material according to conjugation tube in higher plants. They found the original mechanism of homologous-heterogenous polyploids and non-integrated polyploids. Thus, they set up a classification system of the genus and species with genome and sub-genome combinations, respectively. It was known as a significant contribution after Mendel's Law of Inheritance, Morgan's Chromosome Theory of Heredity, and Hitoshi Kihara's Genome theory in Triticeae. And they also revised ?skell L?ve's classification system. Based on this study, they re-classified about 6100 Triticeae germplasms collected by them, including 193 species from 21 genera. Theycharacterized the chromosome numbers of 40 species, found ten new species, and named two new genera Kengyilia and Douglasdeweya.

Professors Chi Yen and Junliang Yang used these germplasms to improve wheat varieties with high yield, multi spikelet, and the resistance of pre-harvest sprouting, such as "Yaanzao", "Datouhuang", "Zuyeqing" and "Fan 6". He improved the strategy of convergent hybridization and selected excellent variety "Fan 6" that became the critical parents of wheat in China. The durable resistance to stripe rust of "Fan 6" remained for more than 20 years.

Professors Chi Yen and Junliang Yang proposed the multiple secondary axis theory. This theory described the essential nature of organs in Gramineae and other plants.