© Springer International Publishing Switzerland 2015 21
M. Molnár-Láng et al. (eds.), Alien Introgression in Wheat,
DOI 10.1007/978-3-319-23494-6_2
Chapter 2
Origin and Evolution of Wheat and Related
Triticeae Species
Moshe Feldman and Avraham A. Levy
2.1 Introduction
Common and durum wheat are among the fi rst plants that were domesticated during
the Agricultural Revolution, about 10,000 years ago. Throughout this period of
cultivation these two crops have been of supreme importance as a staple food that
facilitated and sustained the development of human civilization. Hence, the origin
of domesticated wheat and their evolution under domestication as well as their
relationships with their wild relatives have been central questions for botanists,
geneticists, agronomists, breeders, ethno-botanists and students of human civiliza-
tion. This great interest has led to extensive cytogenetic, molecular, and evolution-
ary studies on the genetic and genomic structure of the various species of the wheat
group (the genera Aegilops , Amblyopyrum , and Triticum ) and on the relationships
among the various wild relatives as well as between them and the domesticated
wheat species.
Given that only a small number of wild genotypes were taken into cultivation,
the genetic basis of domesticated wheat in the early stages of cultivation was rela-
tively narrow representing only a fraction of the large variation that exists in their
wild progenitors. Yet, during the 10,000 years of wheat cultivation the genetic basis
of domesticated wheat has been broadened to some extent due to mutations and
sporadic gene fl ow from their wild progenitors and other related species in Southwest
Asia. Moreover, the tendency of traditional farmers in many parts of the world to
grow a mixture of genotypes in one fi eld (polymorphic fi elds) that hybridized and
recombined made possible a selection of genotypes that were more desirable to the
farmers. Selection pressure was thus, exerted consistently but in different direction
M. Feldman (*) • A. A. Levy
Department of Plant and Environmental Sciences , The Weizmann Institute of Science ,
Rehovot , Israel
e-mail: [email protected]; [email protected]