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There is significantly high ecological plasticity of the root system in different ecotypes of Kochia prostrata (L.) Schrad growing under extreme desert conditions. Variations in the number of somatic chromosomes were found in these ecotypes. The mitotic index (MI) was checked in the region of 0 to 35 mm from the root apex and a significant dependence on seedling height and the time of day was found. Polymorphism of somatic root cells was found in ecotype hybrids. Aneuploid (2n=35 or 37) chromosomes and mixoploids plants were found in introduced old aged(10 - 12 years) populations. The average number of these cases appeared to be very small (0.05%). Insignificant differences of chromosome morphology were found. The genome of diploid forms (2n=18) mostly has metecentrical type of chromosomes, while the tetroploids consist of submetacentrical ones. The chromosomes are short and thickened. We found a high polymorphism of cell size, plasma-nuclei correlation, and number of root chromosomes in tip tissue. The possibility of using cytological peculiarities, as well as certain cytoembryological properties (for example, mitotic index, sizes, fertility and viability of pollen grain, thickness of exine, or dynamics of pollen tube growth) as diagnostic indicators of productivity with introduced selections and the level of their adaptability to desert condition is discussed. The best prospects for selection of kochia species are polyploid forms. The cytological results obtained here confirm the interspecies systematics of Kochia prostrata (L.) Shrad, worked out earlier by U. Pratav (1971).