Review of modern solutions for increasing the rhygenesis of green cuttings Ribes nigrum L

The article presents review materials concerning the search for ways to increase the rooting rate of cuttings of black currant (Ribes nigrum), carried out by Russian and foreign scientists from 2005 to 2020. Being one of the most important berry crops of temperate latitudes, currants occupy ever larger areas of planting in amateur and industrial gardening, which poses the task of nursery growing to increase the production of planting material. Among the modern methods of vegetative propagation of currants, green cuttings are of primary importance. To increase the rhizogenic activity of currant cuttings, methods have been proposed to increase the efficiency of growth stimulants, substrates, and the practice of using fertilizers with prolonged action is shown. The results of studies on the influence of growth stimulants "Zircon", "Epin", "Epin-extra", "Kornevin", "Biostim", "Ukorenit" on the rooting rate of green cuttings of various varieties of black currant are reflected; by the effectiveness of doses of the drug A-1 of plant origin with fungicidal and growth-stimulating activity; the method of green cuttings using glycoluril powder is considered. The response of cuttings to the use of new compositions to increase rhizogenesis is shown, where various modifications of biogenic iron hydroxide nanoparticles are added to β-indoleacetic acid: colloidal nanoparticles of «pure» ferrihydrite (Feh) and ferrihydrite doped with aluminum (Feh_Al) and cobalt (Feh_Co); as well as the effectiveness of soaking cuttings in a solution of zinc oxide nanoparticles. Methods of increasing the effect of the substrate on the rooting of currant cuttings are given: the addition of vermicompost, soil conditioner, long-acting fertilizers agrovitaqua - AVA and zeolites enriched with mineral fertilizers. The addition of a suspension of zinc oxide and platinum oxide nanoparticles to the substrate inhibits root formation in green cuttings of black currant.