PECULIARITIES OF BIOECOLOGY OF HARMFUL VIRUSES IN APPLE PLANTS

Abstract

The prevalence of harmful viruses of Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV), Apple chlorotic leaf spot virus (ACLSV), Apple mosaic virus (ApMV), depending on the location, age, and varietal composition of plantings, was studied. Sandwich ELISA was used in serological tests. Diagnostic kits from «Loewe» (Germany) were used for the analyzes. Leaves were taken as samples. The results of the analysis were recorded using a «Stat Fax 2100» photometer. On apple varieties and clonal rootstocks, the frequency of viruses was 36-54 % and 24 %, respectively. In the Moscow region, the ASPV virus (23 %) prevailed, in the Ryazan region — ApMV (33 %), in the Yaroslavl region — ACLSV (54 %). At the end of the 20th century, the ACLSV virus was more often detected on the apple tree, and in the last decade, we have established an increase in the infection of this crop with the more harmful ASPV and ASGV viruses. The highest prevalence of latent viruses was noted on old domestic apple varieties and foreign varieties (50 % each). A tendency to an increase in the indices of infection with most of the studied viruses was revealed with an increase in the age of trees. In apple trees of old age (over 20 years), the indices of infection with the ASPV virus increased by 25 %, ASGV — by 20 %, ACLSV — by 43 % compared to middle-aged trees (8-10 years). Apple plants of 15 varieties and apple rootstocks of  2 forms 54-118 and 57-490 were found free from the main harmful viruses