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Comparative study was made of the rhizospheree microbiomes of two cultivars of sorghum (Sorghum bicolor cvs. Sucro 506 and Biomass 133) grown on soils with anthropogenic polyelement anomalies and on a background (control) soil. The study used traditional culture-based and culture-independent metagenomic approaches. In soils contaminated with heavy metals, we found decreased numbers of culturable bacteria and quantitative changes in the populations of actinomycetes and micromycetes. The relative abundance of the families whose members were able to resist heavy metals was found to increase in the rhizospheric communities. The taxonomic profile of the microbial communities at the phylum level did not differ significantly between cultivars. The Shannon diversity and the abundance of actinomycete families in the rhizosphere of cv. Biomass 133were greater than those for cv. Sucro 506. Significant differences were found between cultivars for the number of rhizospheric microorganisms resistant to heavy metals.

Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas-starting from biology, analytical chemistry, via health physics, up to social and economic issues-have surpassed mental barriers of individual scientists, so that "production" of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific "hobby" of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the "meaning" of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.

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Study of rhizospheric microbial communities of plants growing under different environmental conditions is important for understanding the habitat-dependent formation of rhizosphere microbiomes. The rhizosphere bacterial communities of four amaranth cultivars were investigated in a laboratory pot experiment. Amaranthus tricolor cv. Valentina, A. cruentus cv. Dyuimovochka, and A. caudatus cvs. Bulava and Zelenaya Sosulka were grown for six months in three soils with different anthropogenic polyelemental anomalies and in a background control soil. After the plant cultivation, the rhizosphere soils were sampled and subjected to metagenomic analysis for the 16S rRNA gene. The results showed that the taxonomic structure of the amaranth rhizosphere microbiomes was represented by the dominant bacterial phyla Actinobacteriota and Proteobacteria. A feature of the taxonomic profile of the rhizobiomes of A. tricolor cv. Valentina and A. cruentus cv. Dyuimovochka was a large abundance of sequences related to Cyanobacteria. The formation of the amaranth rhizosphere microbiomes was largely unaffected by soils, but cultivar differences in the formation of the amaranth rhizosphere microbial structure were revealed. Bacterial taxa were identified that are possibly selected by amaranths and that may be important for plant adaptation to various habitat conditions. The targeted enrichment of the amaranth rhizosphere with members of these taxa could be useful for improving the efficacy of amaranth use for agricultural and remediation purposes.