SPREAD OF POTATO VIRUS Y IN AGROCENOSES OF UKRAINE

Abstract

Objective. Study PVY spread at the territories of the regions of Chernihiv and Kyiv. Methods. Laboratory (virological, immunological, electronic microscopy), field, statistical. Results. Data as of 2009–2023 show a significant PVY spread as monoinfection and in combination with other viruses, which carries significant risks for the seed potato production system in the regions of Chernihiv and Kyiv, Ukraine. The share of complex infections with the presence of PVY in affected samples in the region of Chernihiv within the period from 2009 to 2016 grew from 19.4 % to 47.8 %. In 2017, PVY was detected as monoinfection for the first time (4.0 %), after which a rapid increase in the share of PVY as monoinfection was reported over the next seven years to the level of 79.2–84.8 %, and the share of mixed infections with PVY decreased to approximately 13.0 %. A similar pattern of the spread of PVY and complex infections with the presence of PVY on seed potato fields can also be seen in the region of Kyiv, namely: of all analysed samples, the number of samples affected by PVY increases from 3.4–10.9 % in 2015–2016 to 24.8–31.1 % in 2022– 2023. Conclusion. It is shown that over the past 10 to 15 years there has been a rapid spread of PVY and complex infection in seed potato fields — from 15.4 % of all tested samples (including virus-free) to 61.7 %, while the growth from 1.0–5.0 % to 15.4 % took more than thirty years as previously monitored. In the affected samples, the share of infections with the presence of PVY increased from 19.4 to 93.1 % in the region of Chernihiv and varied from 21.8 % to 98.8 %, depending on the year, in the region of Kyiv. This suggests the need for more careful attention to the varietal composition of seed material and the use of only PVY-resistant potato varieties. It has been also shown that the main causative agent of common (rugose) mosaic of the entire spectrum from mild latent with light undulation to acute one with undulation and deformation of the leaf plate is PVY and its complex infections (mainly PVY + PVM), which requires changes to the regulatory documents certifying seed potato fields.