Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: December 4, 2009
Publication Date: October 18, 2010
Citation: Wang, R. R.-C. 2010. Chapter 2 - Agropyron and Psathyrostachys. In: Chittaranjan Kole (ed.), Wild Crop Relatives: Genomic and Breeding Resources, Vol. 6, Cereals. Springer, Heidelberg. Pp. 77-108. doi 10.1007/978-3-642-14228-4_2
Interpretive Summary: Wheatgrasses and wildryes (Agropyron and Psathyrostachys, respectively) are generally adapted from subhumid to arid climatic conditions in steppe or desert regions. Wheatgrass and wildrye grasses have been mainly used as forage crops. They are also served as the tertiary gene pool for wheat improvement. Many of these wild species have been crossed with wheat (Triticum aestivum L. and T. durum Desf.) and barley (Hordeum vulgare L.). Some specific subjects of alien gene transfer from wild Triticeae into wheat have been extensively reviewed and discussed. Because species of various known genome constitutions in the perennial Triticeae (i.e., P, St, Ns, E, ESt, StH, StY, StHY, StWY, and NsXm, etc.) have been successfully crossed with wheat, all species in the genera Agropyron, Pseudoroegneria, Psathyrostachys, Thinopyrum, Elymus, and Leymus are theoretically capable of being hybridized with wheat. Hybrids, natural or man-made, between wheat and these species had been generally called Agrotricum. The use of wheatgrasses and wildryes as forage crops had been recently reviewed. Thus, only the contribution of specific wheatgrass and wildrye species to wheat improvement will be reviewed in this chapter.
Wheatgrass and wildrye grasses are some of the most important grasses in the temperate regions of the world. These drought-resistant grasses are excellent sources of forage and habitat for livestock and wildlife; and they are valued for weed control, habitat use, soil stabilization, and watershed management. Many of these grasses are related to and have been hybridized with cultivated cereal crops including wheat (Triticum ssp.), barley (Hordeum spp.), and rye (Secale cereale L.) as genetic sources for disease resistance, salinity tolerance, and other traits. The use of wheatgrasses and wildryes as forage crops had been recently reviewed. Thus, only the contribution of specific wheatgrass and wildrye species to wheat improvement will be reviewed in this chapter. This chapter describes (1) basic botany of the species, (2) their roles in elucidation of origin and evolution of allied crop plants, (3) development of cytogenetic stocks and their utility, (4) classical and molecular genetic studies, (4) crop improvement through traditional and advanced tools, (5) genomics resources developed, (6) the scope for domestication and commercialization, (7) some dark sides and their addressing, (8) conservation initiatives, and (9) recommendations for future actions.