This book discusses the natural classification and biosystematics of Triticeae, and presents the most significant findings of comprehensive studies on the Triticeae, an important tribe in the grass family (Poaceae) that includes major crops such as wheat, barley, rye and triticale, as well as various forage crops found in different genera. The five-volume Chinese version of Biosystematics of Triticeae was published in 1998, 2004, 2006, 2011, and 2013, and included the 30 genera, 2 subgenera, 464 species, 9 subspecies, and 186 varieties of Triticeae identified to date. This completely revised English edition features up-to-date international research and the latest advances in the field. The book is divided into five volumes, covering a wide range of disciplines from traditional taxonomy and cytogenetics, to molecular phylogeny. Volume I, Triticum-Aegilops complex focuses on the taxonomy and generic relationships of Triticum and Aegilops, discussing the origin of common wheat as a crop. Volume II highlights the taxonomy and systematics of Secale, Tritiosecale, Pseudosecale, Eremopyrum, Henrardia, Taeniantherum, Heteranthelium, Crithopsis, and Hordeum.