Kurdyukova E.A., Kurdyukov A.B.
Amurian zoological journal 2021; 13(1): 36-53
S its number and the degree of field infection in the Primorsky Region, soil samples were gathered from soybean fields in 2018-2019. At that time, 95 patches with the area of 1 ha each were investigated in eight municipal districts of Primorsky Region. Collected soil samples were examined for presence of SCN cysts, the cysts were measured and their content analyzed, the productivity and viability of cysts in the samples were assessed. Materials describing the population parameters and distribution of H. glycines in the study region at the present time were obtained. The dynamics of the quantity and quality of cysts, as well as their contents during the growing season of their main host - soybean - were traced. Cysts of H. glycines were found in 55,8% of all surveyed soybean patches. Viable cysts accounted for 41- 50% of their total number. Strong and moderate degrees of infection were detected in 58,5% of the total number of infected field plots. The relationships between the number of eggs and size of cysts, the color and size of cysts, the productivity of females and the number of cysts in the sample, the infestation of fields by ruderal vegetation and the number of H. glycines were found. It was established that in the conditions of the Primorsky Region only nematodes of the main wave of the first generation have time to complete the full development, nematodes of the second generation wave remain immature by the end of the growing season and contain a small number of eggs, the share of cysts of the first generation accounts for 64,4% of their total number, and the share of the second - 35,6%.
