ECOLOGY AND GENETIC DYVERSITY OF ANNUAL SPECIES OF CHENOPODIACEAE WITH С4 PHOTOSYNTHESIS

Genetic diversity in 12 annual C4 species of Chenopodiaceae with different subtypes of photosynthesis (NAD-ME or NADP-ME) and ecological group (desert halophytes and psammophytes, ruderal) was studied. Our results indicate that differences in ecological groups are more reflected on genetic diversity than on population structure. Desert species adapted to specific, harsh conditions of soil salinity and/or drought, are characterized by lower genetic variation, compared to ruderal species occupying wider and more favorable ecological niche. The highest deficit of heterozygotes is formed in populations of halophytes represented by C4 NAD-ME species. These species are also characterized by the highest content of toxic sodium ion in plant tissues, which can affect reproductive organs and seed formation. Sensitivity to deficit of potassium ions of C4 NADP-ME plants (compared to C4 NAD-ME) limits their ability to occupy large areas, forcing «to seek» places with required level of potassium in soil. This is possible reason of formation of small and isolated populations