SUSCEPTIBILITY TO CERTAIN TYPES OF SCAB IN THE KARELIA’S CONDITIONS

Abstract

The article presents the results of a three-year field experiment to study potato yields, as well as the incidence of Kholmogorsky (early ripening) and Nevsky (middle early) varieties with black scurf and silver scurf when planting visually infection-free seed tubers with varying degrees of growth cracks. Tuber cracking can be caused by abiotic, biological and anthropogenic factors. Tuber cracking leads to a decrease in the marketability, an increase in waste during mechanical peeling of potatoes, an increase in the likelihood of its infection with pathogens. It was found that the maximum shortage of the crop was detected with the greatest degree of fracturing of the seed material. The use of tubers with such a defect for planting caused a 1.1–fold decrease in the yield of the studied varieties relative to the controls - without growth cracks. With the intensification of the development of functional disease on potatoes, the prevalence of black scurf increased (by 8.3) and silver scurf (7.6%), especially in the early-maturing Kholmogorsky variety.