Selenium (Se) and iodine (I) are essential elements for humans, and their deficiency is widespread throughout the world. In order to obtain a functional nutritional product with an increased content of these trace elements in the vegetative experiment, foliar biofortification of two chervil varieties with selenium (sodium selenate 10 mg/l) and iodine (potassium iodide 100 mg/l) was carried out without and against the background of the use of silicon-containing fertilizers Siliplant (3 ml/l). The combined and separate application of selenate, iodide and Siliplant increased plants’ biomass. Siliplant utilization increased the accumulation of iodine by 1.7-1.9 times, and selenium supply – by 2.2-3.1 times. A significant increase in ascorbic acid content was provided by the combined supplementation of iodine and selenium (1.25-1.27 times), iodine and silicon (1.46-1.87 times) and joint application of selenium, iodine, and silicon (1.31-1.73 times), while an increase in total antioxidant activity (1.3-1.4 times) was observed for (Se+I) and (Se+I+Si) treatments. High varietal differences in the responsiveness of plants to the selected treatments were manifested, particularly an increase of polyphenols accumulation under separate and joint treatments of chervil with iodine and selenium by 1.26 times in the cultivar 21-20, and the absence of a significant effect in the cultivar 24-20. Taking into account the adequate consumption levels (ACL) of iodine and selenium, 50 g of the resulting functional product can provide up to 79% of iodine ACL and up to 40% in selenium ACL.

Selenium deficiency is widespread among the human populations  of  different  countries  of  the world  and associating with cardiovascular diseases and cancer that determines the necessity to develop new technology needs to increase selenium accumulation levels by agricultural crops. Besides that, the utilization of selenium containing food supplements, soil and foliar application of selenium salts are the most popular approach to  resolve the selenium deficiency  problem.  At  the same time there is a certain drawback of selenium plant biofortification, which is a low accumulation of the element, and as a result, the possibility of environmental pollution caused the element. The review is devoted to a new direction in improving plant selenium accumulation via utilization of rhizobacteria; their participation in selenium cycle; mechanism of bacteria-selenium-plant interaction; the role of volatile compounds, released by rhizobacteria, on selenium accumulation. The questions that were separately considered were regarding rhizobacteria Microbacterium oxydans extracted from Cardamine hupingshanesis that had an exceptionally high resistance to selenium impact and ability to synthesize selenocystin.