ФИТОСАНИТАРНЫЙ МОНИТОРИНГ ПОСАДОК КАРТОФЕЛЯ В УСЛОВИЯХ ЦЕНТРАЛЬНОЙ ЯКУТИИ

Abstract

The paper presents the results of many years of research to identify economically significant pests in the agroecosystems of potatoes in Central Yakutia. The species composition of harmful organisms is represented by species - rhizoctonia, alternaria, fusarium, phomosis, late blight, ring rot, black leg, juvenile and perennial weeds, wireworm. Planting material in potato farms is affected by the sclerocial form of rhizoctonia up to 40%, ring rot - 0.2-3.0%, wet bacterial rot - 0.1-3.7%, tubers affected by late blight are rare - 0.4%. Juvenile weeds have high productivity and a large stock of viable seeds in the arable horizon, the dominant species is thrown back - 15 million pieces / ha (83.6%). Perennial weeds have a reserve of powerful underground vegetative mass, such as creeping wheatgrass. The level of soil infestation by the fungus Rhizoctonia solani is high, the population density in permafrost soils was 27.7 to 69.6 propagules per 100 g. soil. The prevalence of Rhizoctoniae on stems ("white leg") on local varieties Yakutyanka - 31.9-45.0%, Severny - 25.0 - 40.6%. The infection of tubers with rhizoctonia was as follows: net necrosis (0.4-6.2%), colonization of the pathogen by sclerotia (7.5-40.4%), deep spotting (0.2-6.5%). The causative agent of the disease of rhizoctonia is a semi-parasite and can persist on plant debris in the soil, like a saprophyte for a long time. So in 2012, on the crops of oats, it was noted - 105.0, sweet clover - 27.7, pea-oat mixture - 93 propagules / 100 g of soil; in 2020 - in the fields occupied by black fallow - 27.7, under fodder crops - 30.0 propagules / 100 g of soil.