Assessment of glutenin and phenotypic diversity of Syrian durum wheat landraces in relation to their geographical origin

Abstract

Glutenin and phenotypic diversity within Syrian landraces composed of Triticum turgidu var. durum and T. aestivum was compared and related to some geographical and climatological characteristics.

Glutenin diversity was determined on the basis of the composition of the glutenin fraction in kernels using Gregorius' level of population differentiation (209-1) — being a modified Nei's measure of gene diversity (H)- and the Shannon-Weaver variation index (I). These two indices were highly correlated. A total of five Glu-A1 and nine Glu-B1 alleles that were not yet described were found. The phenotypic diversity was determined on the basis of the coefficients of variation of ten phenological and morphological traits.

A highly significant positive correlation coefficient between the glutenin and phenotypic diversity indices was found. Both diversity indices were positively correlated with annual precipitation, minimum January temperature and altitude of the collection site. There was a negative correlation between genetic diversity and the maximum August temperature. Correlation of site characteristics was stronger with the glutenin diversity indices than with the phenotypic diversity index.

Further could be concluded that all common glutenin alleles can be found in the landraces from the western coastal and mountainous part of Syria.