Leaf-feeding phylloxera decreases the photosynthetic activity of a grape plant, leading to decreasing number of fruit buds. In addition, phylloxera larvae emerging from the leaf galls may colonize the roots, negatively affecting the growth of the grape plant. In this study, we evaluated host tolerance of three grapevine hybrid populations obtained from crossing of the same maternal grapevine M. no. 31-77-10 with interspecific hybrids carrying introgressions from Muscadinia and other North American Vitis species against leaf-feeding grape phylloxera. Combining genotyping data of the populations obtained with 12,734 SNPs and their resistance phenotypes evaluated in the laboratory experiment, we performed an association study. As the result of GWAS, nine SNPs with the lowest significant p-values were discovered in the whole sample of 139 hybrids as associated with variation of the scores ‘the percentage of infested leaves’ and ‘intensity of gall formation’. Three of the SNPs on LG 7 were located in the same chromosome interval where a major QTL (RDV6) for root phylloxera resistance was reported from Muscadine background. Two SNPs on LG 8 were detected within the gene, encoding E3 ubiquitin-protein ligase UPL4 involved in apoptosis. SNPs detected on LG 13 and LG 18 may overlap with the previously reported QTLs for phylloxera resistance inherited from V. cinerea.
31 March 2022 in Russian Journal of Biological Invasions
The Asian ladybird Harmonia axyridis is an invasive species that is rapidly spreading around the world. Occupying new territories, H. axyridis often causes a decrease in the biodiversity of native species of coccinellids, competing with them for food resources. A comparison of H. axyridis with six species of ladybirds was made in terms of the ratio of the number of individuals and the degree of infestation with parasitoids. In the city of Moscow, the most widespread species of ladybirds was Adalia bipunctata (67.1%); H. axyridis ranks second (16.5%). The total infestation of H. axyridis pupae with parasitoids is 1.8% in Moscow and 12.2% in Yalta. Infestation with parasitoids of other ladybird species in Moscow is much higher: from 11.0% to 36.4%. Thus, parasitoids effectively regulate the number of the native ladybird species, but have an insignificant effect on the number of the invasive species H. axyridis.
The current status of the global organic viticulture is discussed. The challenge of conservation of species and landscape biodiversity in the Crimea is actualized. The fauna of mites and other insects in the grape agrocenosis of the South Coast of the Peninsula is reported. Biodiversity of mites and other insects in commercial vineyards at different pesticide loads is shown. The role that wild-growing vegetation in territories adjacent to vineyards plays in the agrolandscape of grape agrocenoses is highlighted. The commonness of species diversity of predatory mites in a vineyard and on its outskirts is revealed. The possibility to rely on natural mechanisms for self-regulation of population numbers of phytophagous mites under conditions of organic viticulture is demonstrated.
Studies on the effectiveness of applying the scheme for organic processing of grape cultivar Bastardo Magarachskiy in comparison with the traditional scheme of protection against the powdery mildew on the background of its strong progression were conducted. It was established, that the organic protection scheme is not inferior to the traditional processing scheme in its effectiveness and influence on the composition of grape berries. The biological effectiveness of the organic protection scheme in vineyards averaged 78.3%. There is no significant difference in grapes obtained in the traditional and organic processing schemes by the mass of the bunch, the concentration of sugars and titratable acids in the berry. The use of biological products in foliar treatment had such beneficial effect on the formation of the phenolic complex of berries as the increase in supply of phenolic substances and growth of phenolic maturity. The use of organic protection scheme against powdery mildew led to a decrease in the concentration of pyruvic acid in juice by 2.5 times on average, compared with the traditional one, and an increase (in comparison with the traditional and control) by 1.4 −1.6 times of the concentration of α-ketoglutaric acid. The studied treatment regimens did not affect the concentration of aldehydes.