Orel L. Allelopathically active substantances of weeds and scientific principles of working out phytoregulators

The dissertation is dedicated to screening of allelopathy active substantances of weeds and working out of phytoregulators with herbicides action. On the basis of discovered plant-donors (Cirsium arvense (L.) Scop., Barbarea vul-garis R. Br., Fumaria officinalis L.) six herbicidie phytoregulators, containing the multi-component, synergetical mixture of fenolic substantances as a working basis. For the first time was investigated the chemical composition of plant-donors (C. ar-vense (L.) Scop., B. vulgaris R. Br.), it was selected complex of substances of lipidic and fenolic nature with high growth-inhibiting effect. It's puted that callus mass, which is recieved from the roots of young seedlings of B. vulgaris R. Br., C. arvense (L.) Scop., and also cultural substance environments from cal-lus mass have growth-inhibiting properties. On the basis of syntetically created naturally working substance secreted from C. arvense (L.). Scop. the herbicide almetid was worked out, which according to the field tests was exposed as efficient in combating dicotyledonous weeds in saving of spring barley and winter wheat. By the results of researches of toxicological characteristics phytoregulators are re-lated to little hazardous substances (class IV of hazard).