ASSESSING THE RESISTANCE оF RARE СITRUS TAXA TO DOMINANT PESTS IN THE HUMID SUBTROPICS OF RUSSIA

Citrus fruits are one of the most common and most important fruit crops that are widely cultivated in countries with subtropical and tropical climates. The humid subtropical zone of Russia is the only place in the country where it is possible to grow citrus fruits in the open ground. There is a collection of 138 samples. The research was carried out on the basis of the bioresource collection of citrus crops of the Federal Research Centre "Subtropical Scientific Centre of the Russian Academy of Sciences" (Sochi) in 2020–2021. The objects were 13 taxa of the genus Citrus, belonging to the category of rare: C. aurantifolia (as well as its cultivars ‘Tahiti’, ‘Foro’), C. × aurantium var. myrtifolia ‘Cinotto’, C. × bergamia, C. ichangensis, C. × limetta ‘Chontipico’, C. limon L. ‘Del Brasil’, C. × limonelloides, C. maxima ‘Sambokan’, C. medica (as well as its cultivr var. Sarcodactylus), C. × meyeri and pest populations found on them. The studies were conducted according to generally accepted methods. The degree of damage to plants was assessed on a 5-point scale. In the humid subtropical zone of Russia, rare citrus taxa are damaged by the following phytophages: red (Panonychus citri McGregor.) and silver (Phyllocoptruta oleivora Ashmead) citrus mites, woolly whitefly (Aleurothrixus floccosus Maskell), citrus leaf miner (Phyllocnistis citrella Stainton), as well as land slugs and snails. C. ichangensis turned out to be the most resistant to the pest complex. The most resistant species to sucking pests and citrus leaf miner over the years of research were C. × aurantium var. myrtifolia ‘Cinotto’, C. ichangensis and C. maxima ‘Sambokan’, which is probably due to the anatomical structure of their leaf apparatus. The most susceptible to sucking pests were such taxa as C. × meyeri, C. × limetta ‘Chontipico’, C. × bergamia and C. medica var. sarcodactylis, to land slugs – C. × limetta ‘Chontipico’ and C. × bergamia.