Contribution a l’étude des caractères morphologiques, physiologiques et des marqueurs moléculaires pour l'évaluation du polymorphisme phénotypique et génétique des espèces du genre Tamarix dans différents écotopes de la zone steppique de KHENCHELA (EST ALGERIEN)

Abstract

In this work we have tried to put the accent on morphological, physiological and molecular markers for the evaluation of phenotypic and genetic polymorphism in the genus of Tamarix in different ecotopes of the steppe zone in KHENCHELA (Eastern Algeria) where such genus had an important interest in the rehabilitation of degraded ecosystems. The study's sites are selected according to a north-south transect across the region where soil, orographic and climatic characteristics are very different Geological, and soil study indicate that the species of the genus of Tamarix holds in different areas, generally alkaline and saline substrates, in a semi-arid and desert climate. The literature review has shown that the genus of Tamarix have a very important reproductive potential, with a root system very suitable for water deficit conditions with a large capacity and it is used in traditional medicine and in modern medicine in Europe. The flora and morphometric analysis allows us to consider the floristic richness of Tamarix group and advance certain assumptions in relation to the environment. In terms of resistance to salinity The results are significant; where the cuttings of Tamarix sp. continued to grow even at a dose of 64g / l of NaCl. Regarding the results of statistical analysis by ANOVA, shows that there is no significance between the effect of salt dose and the accumulation of proline. The results of the study of primary metabolites, secondary metabolites and the antimicrobial activity revealed a highly significant effect of the environment on their quantity and quality. The study of genetic polymorphism in species of the genus of Tamarix, using molecular marker PCR-SSR type showed that the accessions studied are genetically very distant because in most cases the dissimilarity coefficients are greater than 50% which explains the large genetic polymorphism between and within species in the genus of Tamarix.