Nepliy L. Wheat barley yellow dwarf and the ways of limiting its harmfulness in the southern steppe of Ukraine

The autumn periods of 2006, 2007 and 2008 in southern Ukraine were arid and favouring active reproduction of aphids and their migration to winter crops. In spring of 2007, 2008, 2009 in the booting - early earing - flowering stages the signs of barley yellow dwarf virus on winter wheat plants were observed. Enzyme-linked immunosorbent assay, polymerase chain reaction analysis and electron microscopy examination have confirmed the presence of barley yellow dwarf virus on the plants of winter wheat varieties under study. The structural analysis of winter wheat on infectious barley yellow dwarf virus background revealed reduction in value of all the yield elements.The quantity of carotenoids, chlorophyll a and b in winter wheat leaves of diseased plants decreased under the influence of viral infection. The amount of total sugars in the plants on the infectious barley yellow dwarf virus background increased. The intensity of wheat damage by barley yellow dwarf virus decreased from early to late sowing. Enzyme-linked immunosorbent assay analysis of the plant material of winter wheat line 34/10, which seeds were treated before sowing with Yunta Quadro, has not revealed yellow dwarf barley virus. This fact demonstrates the high efficiency of the preparation against insects and in its turn against yellow dwarf barley virus which is carried by insects.