Microsphaera viburni (Duby) S. Blumer: Ecological and biological features, methods of control in the system of ornamental and fruit horticulture

Abstract

The research relevance is determined by the need for a comparative assessment of different viburnum species in terms of resistance to powdery mildew, a disease that inhibits physiological processes in plants, negatively affecting growth, development, and yield, as well as decorative effect. The research aims to study the bio-ecological characteristics of Microsphaera viburni (Duby) S. Blumer and to develop measures to control powdery mildew in viburnum orchards. During the experiment, methods and techniques were used to conduct phenology, create provocative backgrounds, assess the level of damage to the ground part, and determine the degree of damage and resistance of viburnum plants. Recommendations for avoiding or reducing the risks of powdery mildew in viburnum orchards are provided. Nitrogen fertilisers should be applied in early spring and avoided in late summer to limit the growth and development of annual shoots, the tissue of which is more sensitive to the powdery mildew pathogen. It has been shown that formative, regulatory, and sanitary pruning in early spring can improve lighting and air circulation in the basal part of viburnum plants, intensify the growth of permanent shoots and form the desired type of bush (tree) in the system of fruit or ornamental horticulture. It has been proved that in the conditions of the Northern Forest-Steppe of Ukraine, it is advisable to grow highly resistant (Anya, Osinnia, Elina, Omriana) and resistant (Kralechka, Plododekorna, Sonetta, Horikhova, Yaroslavna) varieties (forms) of European cranberrybush of the Institute of Horticulture of the National Academy of Agrarian Sciences of Ukraine against powdery mildew. It is recommended to use resistant and mediumresistant varieties of common dwarf viburnum ‘Eskimo’ and common ‘Roseum’ for ornamental gardening (Viburnum opulus Roseum). The practical value was in a determination that powdery mildew of European cranberrybush ‘Roseum’ does not affect other species of the genus Viburnum L. under artificial inoculation; it was confirmed that the susceptibility of viburnum plants to this disease can be significantly reduced by low-susceptible and resistant varieties and species of the genus Viburnum L. and timely agronomic measures