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Gardening is one of the most perspective branch of agriculture in southern - western part of Ukraine. It develops dynamically. The natural environment is favorable for the developing classical and intensive gardening. The enough number of heat and light, moderate water providing in summer period, rather mild winter, enough able soils and rich experience of gardeners allow to grow the seedlings high- grade sorts of pome fruits: apple, pear and quince. There are 1,3 % of land owning in Ukraine, so the southern-western region has 4% of planting for pome fruits from the general number. The general area of perennial plants in the region was 28.7 thousand ha, the poam fruit trees took 20,9 thousand ha, they belonged to the intensive type gardens. The tendency of fruit plantations increasing is observed every year. The present region characterizes the highest temps for the new gardens planting. The garden’s area increases on 450-500 ha every year. The probability of poam trees’ diseases by pests and diseases is increased by the gardening development in this region. Viral diseases by their damage are not complied with fungal and bacterial diseases, but sometimes they are exceed by their harmfulnes. These viruses are obligate parasites of plant cell, so it makes the struggle with them very hard. The viral diseases of poam trees have permanent character. If the tree was ill, it would be ill during all it’s life. The compilation from the ill trees will come to the next spread of viral diseases. There are defined the following vital and micoplama’s diseases of poam trees: apple- mosaic, proliferation, apple’s wood softening, disease flat branches, fruit’s green crinkle, star fruit cracking, microcarpous of fruits, pear- ring mosaics, yellow veins leaves, stem pitting, fruit stone, death of pears. There were determined the range of additional viruses for apple and pear. There were determined the following viruses: apple chloratic leaf spot virus, apple stem pitting virus group, apple spy, apple stem grooving. There are characteristics for some viral diseases. Apple mosaic virus is the representative of genus Іllarvirus . It has wide natural spread in the range of natural hosts. It infects many plant trees, for example: apple, plum, almond, apricot, hop, hazelnuts, birch, horse chestnut, raspberry, rose (and other species from the family Rosaceae) and etc. It is spread throughout the world. It’s concentration changes during the year. The biggest concentration of this virus usually saves on the young leaves. Apple chlorotic leaf spot virus is filamentous, willowy or striped capsid with rope-like particles by length 680-780 nm and width 12 nm and linear sense –positive ssRNA, it may runs together by the mechanical conditions of plants. It belongs to genus Trichovirus and family Flexiviridae . They usually exist in latent form. It infects the plum’s leaves, pear, cherry, apricot and other garden plants, which belongs to the order of Rosales. Apple chlorotic leaf spot virus is a representative of KLOSTERO group viruses. They are able to colonize the meristematic cells and decrease the stimulating effect from the tissue culture. It is experimentally confirmed that the Apple chlorotic leaf spot virus consist from the RNA by the weight 7555 kb nucleotides. It runs from one plant to another plant vegetative, mechanically through the cells liquid by: seeds, mistletoe, nematode, fungis. Apple stem pitt ing virus gro u p is a representative of family F lexiviridae from genus Fovea viru s by spherical shape 30-34 nm. It is localized in cytoplasme cell. The symptoms of defeat appeared on the poam fruits through 10-20 days after petals abscission in the form of dark-grey spots under the epidermis. The spots usually locate by rings. The crumb growing is stopped in infected parts, but the surrounding tissues develop normally. The tissues deforms in a result of disease development. The deep grooving develops in the result of grooving. The tissues are in the depth of grooves necrotize very often. Sclerenchyma’s mechanical cells are appeared in the affected areas. The symptoms appeared in less favorable conditions only in July- August in the form of non-deep circular. Sometimes the fruits are defeated on separate branches. The ill spreads vegetative, together with planting material. It was determined the slow spread of the disease in the garden. Though the disease agent is not determined. Sometimes the veins are yellow on the leaves. The chloratic spots appear. The crack appears on the body of the tree and branches. The trees lose the resistance to the frost and to sudden temperature fluctuations. The trees die before time. The virus’ harmfulness comes to the crops losses on 40-50%. Apple stem grooving virus gro u p is a representative of family Betaflexiviridae genus Capillovirus of rope-like form. It’s length 1200 and width 12nm. The infected symptom appear on the wood under the body of the tree and skeletal roots in the form of wide flat sulcate, spots and separate brown spots in the place adhesive rootstock- scion. There are well noticed the inflation, cutting, necrotic spots and dark-brown or black lines on the surface of the bole’s bark. It spreads by the mechanical way, at the conditions of cutting, together with planting materials and seeds. The infected trees are the source of infection. The virus saves in the trees moisture. As a rule, latent viruses infect sorts and rootstocks will not cause clear external symptoms. The viruses harmfulness are expressed in trees’ weak growing and developing. The infected trees have hypersensitivity to frost and other non-favorable environment factors. It is impossible to treat the viral infected trees, that is why the preventive measures played important role in the struggle with viruses. They must prevent from the disease appearing and their spread. It is necessary to use virus-free or tested planting material for the setting up uterine and industrial plantations. It allows to increase the planting material’s vegetative productivity and garden’s yield’s increase. There are determined the following kinds and modifications of serological tests in virology and phytovirology. These methods allow to diagnose, identify and reveal viruses in very small concentrations. The immune-enzyme analysis is one of the sensitive serological tests. It allows to reveal and identify viruses in dependence upon the particle’s morphology. The data collection and processing of phytovirology published data about poam trees and determining the appropriateness for phytovirological monitoring of poam trees by ELISA. So this method was determined as priority and the following way of our investigations. |
