Fruit growing
and viticulture of South Russia

Annotation

Important aspects of the vital activity of the root Poncirus trifoliate Raf. � the main rootstock for the genus Citrus under the conditions of the subtropics of the Caucasus Black Sea coast are considered. The root system is not only an organ of absorption, excretion and metabolism, but also the interaction of underground and aboveground organs. The study of the power and nature of the structure of the root system, the depth of its infiltration into the soil is of great practical importance for characterizing soil fertility. The growth pattern of the above-ground and root systems of mandarin grafted on P. trifoliata should be taken into account at determining the area of plant nutrition during bedding. The root system of seedlings of Unshiu mandarin variety at the age of 1-2 years is characterized by specific features: primary roots have very few root hairs, the functions of which are performed by mycorrosis, which explains the need for aeration and hydration of the roots. The bulk of the roots of Unshiu mandarin seedlings on the P. trifoliata rootstock is located at a depth of 0-20 cm, and a smaller part � at a depth of 20-40 cm. Most often, the root is interpreted as an organ that receives water with elements of mineral nutrition. However, the study of root systems makes it possible to develop agrotechnical methods of influencing on plants. The absorptive activity of the citrus root is given special attention due to the absence of root hairs, which are replaced by mycorrhiza. Mycorrhiza is a complex symbiosis of trifoliate roots and fungal mycelium. Over the years of evolution, their interaction has become necessary for each other. Therefore, the improvement of the soil environment in the root habitat zone is favorable for the growth and generative processes of citrus plants.

Annotation

The main breeding techniques used in the 50s of the 19th century by breeder F.M. Zorin � creator of the Friendship Tree, candidate of agricultural sciences (1944), are considered. Fyodor Mikhailovich developed valuable varieties of mandarin oranges, grapefruits, lemons, plums, figs, and hazelnuts. Author of more than 40 scientific papers. He was awarded the State Prize for the creation of new varieties of fruit plants. This article shows theoretical research and practically used methods for breeding new varieties of citrus fruits. The basis of his research was vegetative hybridization (from Greek �hybris� � inbreeding) � the production of hybrids by grafting. Zorin F.M. paid a special role in the breeding work to �tree gardens�, which were of both scientific and industrial importance. Fruits from such a tree could change shape, size, color and ripening time. At the same time, he paid attention not only to the selection of the scion, but also the rootstock. As a result, such a tree had many trunks, and the crown consisted of numerous varieties and species of three genera � Citrus, Fortunella, Poncirus of the Rutaceae family. Almost the entire Pomeranian subfamily (Aurantioideae) grafts onto each other and is highly compatible. It is important to take into account varietal characteristics: timing of flowering and ripening, as well as their biology. The main advantages of citrus �tree-gardens� are the saving of garden space, the aesthetic appearance of the trees and originality, as well as the ability to obtain more varieties per unit area.