Every third medical product in the world market is an herbal preparation. Preparations from the roots of medicinal genus Rheum species, Polygonaceae family, for the treatment of cardiovascular, gastrointestinal diseases, and as antitumor agents are used. The food-consumed petioles of the vegetable rhubarb are used in the food industry. Vegetable rhubarb petioles contain 1,0% organic acids, from 1,0 to 2,5% pectin substances and up to 3,2% of dietary fiber, as well as minerals and vitamins. The vegetable rhubarb petioles consumed fresh, in canned, dried, frozen form and are used for the preparation of a products variety with a high vitamin value. In our research, we used biologically active phenolic compounds (emodin, resveratrol, quercetin) of extracts from the roots and leaves of R. raponticum plants harvested in the period 2012-2016. In order to obtain practical data on the spectrum of action of Rheum extracts, the species belonging to different systematic groups were used as test objects: Mycota - Fusarium moniliforme Sheldon; Fusarium graminearum Shwabe, Fusarium sporotrichiella Bilai, Sphaerotheca fuliginea Poll. Extracts exhibit fungicidal and stimulatory properties. In view of the variety of possibilities for the economic use of Rheum plants, the simplicity of the agricultural techniques of cultivation and reproduction and the absence of significant losses from diseases and pests, we can recommend the creation of rhubarb plantations and its complex processing in the Republic of Moldova