Influence of Abiotic Factors on the Dynamics of Number of Wheat Phytonematodes

The purpose of the research is to study the effect of abiotic factors on the dynamics of the number of wheat phytonematodes in conditions of Uzbekistan Response of ecological groups of plant nematodes to changes in living conditions. Materials and methods. To study the dynamics of the number of wheat plant phytonematodes and its root soil in the conditions of Uzbekistan, soil and plant samples were selected by the stationary method every month, starting from March to June during 2012–2016. To isolate nematodes, a modified Berman funnel method was used. For the presence of cyst-forming nematodes in the soil, they were analyzed by the Decker method. In determining the species of plant nematodes, an atlas of plant nematodes compiled at the Institute of Parasitology of the Russian Academy of Sciences was used, as well as morphometric parameters obtained using the generally accepted formula de Mann.Results and discussion. In the wheat field during the growing season, 96 species of nematodes were recorded. A variety of species of plant nematodes both in the roots and in the root soil of wheat, the largest number of plant nematodes falls on the beginning of the study (March), then their density begins to decrease sharply and reaches a minimum at the end of the growing season (June). In the aerial parts, the number of species of plant nematodes occurs in the middle of spring (April), then in the following periods a decrease in numbers is observed. The smallest number is observed in the summer period before harvesting. The registered phytonematodes were distributed to the following ecological groups: polytrophs – 11 species, typical saprobionts – 4 species, devisaprobionts – 30 species, potential parasites – 43 species, true parasites – 8 species. Ecological groups of phytonematodes react differently to changes in living conditions. At the same time, the effect of environmental factors depended on the habitat of the plant nematodes.