Etude moléculaire du polymorphisme des protéines de réserve d’une accession de blé dur (Triticum durum Desf. ) Cultivé en Algérie.

Abstract

The managment and conservation of genetic ressources of a cultivated specie must requir a good knowledge of its morphological and genetic variability for its conservation against its erosion. For this we have carried out an agro-morphological, biochemical and molecular study, in order to appreciate the morphological and agronomical diversity intra and inter-varietal, as well as the polymorphism biochemical and genetic of reservation’s protein (glutenins HPM, FRM and the gliadins) existing among the 100 genotypes belonging the four local varieties of durum wheat (Triticum durum Desf .) ,namely, alexandrinum, merciense, valenciae and italicum cultivated in Algeria. The measurments of agro-morphological parameters were carried out at plants maturity. The results obtained by of agro-morphological parameters showed the existence of a very important inter-varietal diversity between the four varieties so that the alexandrinum and italicum variety’s genotypes have the highest performances values, while murciense variety’s genotypes show the lowest values. The biochemical analyse by one-dimentional electophoresis (SDS-PAGE) revealed the presence of low intra-varietal polymorphism and important polymorphism between the genotypes of four varietes ; the genotypes of alexandrinum and murceinse variety have - - gliadins bands, while the gemotypes of valenciae variety present type et gliadins bands. Molecular study include three technical’s type , namely PCR/BULK technical, molecular marking across the PCR/RELF marker and genes’s sequencing coding gliadins. The two primers GLUDX5 and LA1 aimed at the amplification of glutenins’s genes highliting the the poverty of these genes in all genotypes of the four varieties. While the primer 56MN used for the amplification of gliadins’s genes wich shows the abudance of these in all the genotypes of four varieties. For the marker PCR/RELF apply on eleven genotypes of four varieties slected on the basis of thier abudance of gliadins’s genes produced the same namber amplifing molecular wheight 536 pb. With eleven monomorphic fragments. The sequencing’s analyse of two genotypes selected of any variety shows the existence of a very weak polymorphism between the genotypes of four varieties and reveal that they are very genetically related.