PATHOLOGICAL PROCESS OF ROOT SPONGE OF PINE IN THE CONDITIONS OF FOREST EDATOPS AND CLIMATE CHANGE STATE ENTERPRISE «ZARICHANSKE FORESTRY»

Topical issues of forest pathological monitoring of Scots pine plantations on old arable lands affected by root sponge, as well as the impact of different soil types and climate change on the degree of damage to 20-35-year-old pine stands are substantiated. The subject of the work is the causative agent of the root sponge of Scots pine, which has become widespread in the old arable lands in the conditions of the State Enterprise "Zarichanske Forestry". The causative agent of the root sponge of Scots pine affects forest plantations aged 20-35 years on lands withdrawn from agricultural use. Climate change, in particular the increased temperature of the above-ground air layer, as well as the decrease in precipitation during June-August, exacerbate the pathological process of the root sponge pathogen of Scots pine, which forms epiphytosis in large areas. The aim of the work is a detailed study of the pathology of the causative agent of the root sponge of Scots pine in old arable lands, as well as the impact of different soil types and climatic conditions on the spread of infection in forest edatops of the State Enterprise «Zarichanske Forestry». The main methods of work are calculation and analytical collection and processing of phytopathological examination of pine plantations on old arable lands, monitoring of the impact of different types of forest soils on the spread of the root sponge of Scots pine in forest edatopes of the State Enterprise «Zarichanske Forestry» and pine stands with determination of the nature of drying depending on the degree of damage by the pathogen of the root sponge with changes in climatic conditions. According to the results of the work it was established that the causative agent of the root sponge of Scots pine affects stands at a young age of 20-35 years, depending on the type of fallow soils used in agriculture, as well as changes in climatic factors. It is established that the increase in temperature in the surface layer of the soil in June-August to +32oC significantly reduces the resistance of pine stands to the pathogen of the root sponge. The scope of the results is the forestry enterprises of the Zhytomyr Regional Department of Forestry and Hunting in order to preserve and protect the incoming pine forest plantations from the pathogen of the root sponge in the Polissya zone of Ukraine. The conclusions of the research are that in pine plantations on old arable lands the decisive role belongs to the pathogen of the root sponge in the curtain drying of pine stands in the conditions of A2-A3, B2-B3 of SE «Zarichanske Forestry». Foci of drying of Scots pine stands are formed on infertile soils lighter in mechanical composition. The decrease in rainfall and the increase in air temperature to +32, + 36oC for the period 2018-2020 has led to a significant decrease in the resistance of pine stands in old arable lands to the pathogen of the root sponge of Scots pine. High density of pine stands at a young age (25-30 years) and stopping the radial growth in conditions of excessive density without active differentiation and timely fall lead to a decrease in the resistance of Scots pine to the pathogen of the root sponge and as a result - their complete drying. In the cells of pine stands from the causative agent of the root sponge, the effect of precipitation during active growth (June-August) is higher than the coefficient of determination r=0.70 p<0.01 than in the adjacent intact stand (r=0.43, p <0.05). This means the leading role of moisture in increasing the resistance of pine stands to the pathogen of the root sponge at 25-35 years of age. Reduction of precipitation from 420 to 210 mm during 2010-2020 in the areas of forest use of SE «Zarichanske LH» with a simultaneous increase in air temperature in the surface layer from 25 to 32 oC is one of the reasons for reducing the stability of pine plantations aged 25-30 years on old arable lands to the pathogen of the root sponge of Scots pine.