Clonal micropropagation of apple trees

Abstract

The purpose of the review is to analyze the state of knowledge of the issue of apple tree reproduction in Russia and abroad. Of all the methods of tissue culture, clonal micropropagation is the most studied, which has a number of advantages in comparison with traditional vegetative multiplication: obtaining healthy material, rapid reproduction, obtaining genetically homogeneous material, the possibility of releasing material throughout the year. Micropropagation has played an important role in the production of healthy, disease-free plants and in the rapid multiplication of apple varieties and rootstocks. This review shows that over the past decades, foreign and domestic researchers, including scientists of our institute, have developed a large number of methods for cultivating of varieties and rootstocks of apple trees. Due to the heterozygosity of the genus Malus, protocols for specific gene types are often developed. The conducted research analysis showed that the successful reproduction of apple trees is influenced by external and internal factors (genotype, physiological state, components of nutrient media, conditions of adaptation of micro-plants). The review reflects various approaches to solving such problems as obtaining an aseptic culture at the initiation stage, reducing the negative effect of phenol oxidation products, increasing the proliferative activity of explants using various nutrient media, as well as natural and synthetic growth hormones - cytokinins, problems of stimulating root formation as a result of the use of various types of auxins and methods of exposure, the development of conditions for the adaptation of microplants of varieties and rootstocks of apple trees in vivo. The emergence of new varieties will require the development of new cultivation conditions.