The Application of Amplified Fragment Length Polymorphism (AFLP) for Breeding MN Efficiency in Durum Wheat (Triticum Turgidum L. Var. Durum)

Abstract

Manganese deficiency is a major constraint on alkaline soil, particularly for durum wheat, which is more intolerant than either bread wheat or barley. Genetic variation exists in current germplasm of durum wheat. In addition the development of a consistent selection criterion and the recent information on the most probable model for genetic control of Mn efficiency (two genes with additive effect) has made breeding for Mn efficiency feasible. The development of a precise and accurate screening technique will accelerate the breeding and also the genetic study of Mn efficiency. This technique preferably should be accurate, fast, less tedious and supplement the current pot bioassay. Marker assisted selection (MAS) is probably the most commonly claimed application of molecular markers in plant breeding. To identify markers linked to a locus conferring Mn efficiency in durum wheat Amplified Fragment Length Polymorphism (AFLP) analysis was combined with a Bulked Segregant Analysis (BSA) in order to increase the efficiency of identifying of markers linked to loci of interest. A total of 64 primer combinations was used to compare the bulk samples with the two parents in an F₂ population of a cross of Mn-efficient (Stjocri 2) x Mn-inefficient (Hazar) durum wheat. Two Primers (Pstl+ACA/Msel+CAA) and (Pstl+ACC/MSEl+CAG) each revealed one AFLP, where the band was present in the efficient bulk and efficient parent but absent in the inefficient bulk and inefficient parent. The AFLPs identified will be tested for cosegregation of the trait by progeny testing the entire F₂ population. If linkage to one or two Mn efficiency loci is confirmed, these markers will provide a valuable selection tool for efficient progeny in further segregating populations bred from the same efficient progenitor.