Integrated review of Psathyrostachy huashanica: From phylogenetic research to wheat breeding application

Enhancing wheat yield and stress tolerance is a critical long-term objective for global food security. Historically, breeders selected genetic traits from wild wheat relatives for domesticated targets, such as non-shattering and free threshing characteristics, and developed the cultivated wheat. However, the genetic diversity of the cultivated wheat has become narrow after long-term domestication and conscious selection, which seriously limited the yield potential and stress tolerance. Therefore, using wild Triticeae species to broaden the gene pool is an ongoing task for wheat improvement. Psathyrostachy huashanica Keng ex P. C. Kuo (2n = 2x = 14, NsNs), a perennial species of the genus Psathyrostachys Nevski, is restrictively distributed in the Huashan Mountain region of Shaanxi province, China. P. huashanica exhibits considerable potential for wheat breeding due to its valuable agronomic traits such as early maturation, more tillers, abiotic tolerance, and biotic resistance. Over the past four decades, researchers have successfully crossed P. huashanica with common wheat and developed derivative lines with improved agronomic traits. Here, we summarized the morphology, genomic evolution, and derived wheat breeding lines with advanced agronomic characteristics inherited from P. huashanica. This review provides a useful guideline for future research on P. huashanica, and highlights its importance in wheat breeding.