Guzyk O. Buckwheat rhabdovirus and formation of resistance to it different plant species

Dissertation is devoted to the study of the response of different plants to buckwheat burn virus, and the ability to form resistance to it. The effect of nuclease activity in various buckwheat varieties on their resistance to buckwheat burn virus was investigated. It was established, that buckwheat plants of Roksolana variety have high nuclease activity and are resistant to buckwheat burn virus, while buckwheat plants of Kara-Dag variety possess low ribonuclease activity and are considerably sensitive to this virus. Resistance to buckwheat burn virus was studied on transgenic tobacco plants that carry bull heterologous pancreatic ribonuclease gene. It was demonstrated that the expression of bull pancreatic ribonuclease inhibits the accumulation of buckwheat burn virus in transgenic tobacco plants. This finding can be used in generation of plants, resistant to phytorhabdoviruses. It was also shown that transgenic potato plants of Kapryz variety, that express Zinnia elegans extracellular ribonuclease gene are not resistant to buckwheat burn virus. The dynamics of buckwheat burn virus reproduction was investigated in tobacco plants expressing human interferon alpha-2beta gene. The critical period that determines resistance of these transgenic N. tabacum plants to buckwheat burn virus was shown to be the first week after infection: high levels of antiviral activity correlated with minimal buckwheat burn virus content in plants by the end of the experiment. It is shown that treatment of Kalanchoe pinnata plants with buckwheat burn virus grants 58± 5 % inhibition of tumor development, induced by Agrobacterium tumefaciens. For the first time some BBV genome parts were amplified and their nucleotide sequence was determined. The analyses of sequenced regions revealed similarities to the gene encoding the sequences glycoprotein and nucleocapsid proteins of various rhabdoviruses.