Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/6/2003
Publication Date: 11/6/2003
Citation: JARADAT, A.A. MACROGEOGRAPHICAL POPULATION GENETICS OF WILD EMMER WHEAT AND ITS ROLE IN SUSTAINABLE AGRICULTURE IN THE FERTILE CRESCENT. CD-ROM. MADISON, WI: ASA-CSSA-SSSA. 2003.
Technical Abstract: Wild emmer wheat (WEW) is the immediate progenitor of tetraploid and hexaploid cultivated wheats. In the Fertile Crescent (FC), the center of origin and center of diversity of WEW, the wild progenitor exhibits a wide phenotypic and genotypic variation and displays a rich adaptive genetic diversity ecologically and genetically structured as an "archipelago." The fertile hybrids, between the progenitor and domesticated durum wheat, point to the early (and current) extensive gene flow that must have enriched the genetic structure of both subspecies in the FC. Specific alleles and allele combinations predominate, at the macro- and micro-geographic scales, as co-adaptive blocks of genes, adapted to diverse biotic and abiotic stresses. WEW is recognized as a source of genes for agronomically important traits. These include genes for large spike and grain size, high grain and protein yield, desirable composition of storage proteins, photosynthetic yield, herbicide response, salt tolerance, disease resistance (leaf rust, stripe rust, powdery mildew, and wheat soil-born mosaic virus), profuse tillering, drought tolerance, and, presumably, genes for other quantitative traits. For millennia, the vast genetic diversity in WEW must have contributed to the spatially and temporally sustainable wheat production, as a major component of dynamic and stable cropping systems in the FC. With the advent of, and easy accesses to, molecular genetics and breeding tools, WEW is expected to contribute the full range of its diversity, in qualitative and quantitative traits, for a more sustainable wheat production, especially in the developing world.