Durum Wheat Adaptation in the Mediterranean Dryland: Breeding, Stress Physiology, and Molecular Markers
From antiquity, food from wheat (Triticum aestivum L.) has been the staff of life for much of the world's population. Wheat is the word's staple food crop, along with rice (Oryza sativa L.). Two main categories of wheat are based on growth requirements and grain quality, and thus end use. As wheat has its origin in the Middle East, both bread wheat and durum wheat are grown here. Durum (T. turgidum L. var. durum) is cultivated extensively in the dryland of the Mediterranean region under drought prone and environmental variable conditions. Drought tolerance research is complex and requires a large number of testing sites and seasons to determine the genotypic drought resistance. Drought tolerance research requires various tools such as the exploitation of the genetic variation of landraces and Triticum wild relatives, use of representative testing environments/sites, stress physiology, and use of molecular markers. Drought resistance is of major interest in International Center for Agricultural Center in Dry Areas (ICARD) dryland durum breeding program; this involves the use of Triticum wild relatives in the breeding; representative testing sites, stress physiological traits, and molecular markers are discussed. Crosses between durum and its wild relatives have generated durum genotypes with better performance under environments with abiotic constraints such as drought and temperature extremes (heat and drought). The carbon isotope discrimination technique showed relatively the largest association with grain yield combined with low genotype-environment interactions and was mapped and the chromosomal region controlling it was identified on 4BS chromosome. The molecular markers are considered as potential tools to be used in marker-assisted selection, to improve drought tolerance and productivity of durum in the Mediterranean region. These techniques will be incorporated in developing targeted crosses and selecting durum improved germplasm.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
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