[Tendencies of nematodes communities to recover after soil cover degradation].

The way nematodes form communities on a new substrate after complete soil and plant cover degradation is studied on a model of industrial dumping. It is revealed that recovery of soil cover after degradation begins with invasion of mainly the upper soil horizon by nematodes. At the early stages, species that are resistant to unfavorable environmental conditions dominate (bacteriophages), next the abundances of carnivores and nematodes that are connected with plants increase, which indicates the process of biocenosis regeneration.

[Effect of the soil contamination with a potato cyst-forming nematode on the community structure of soil-inhabiting nematodes].

Nematode community structure of the potato fields with different infection levels of potato cyst-forming nematode (PCN) such as 10, 30 and 214 cysts per 100 g of soil has been investigated. The influence of specialized parasite on nematode fauna and dominance character of different ecological-trophic groups were described. Parasitic nematode genera in natural meadow biocenosis and agrocenoses without PCN are Paratylenchus, Tylenchorhynchus, and Helicotylenchus. It is established, that Paratylenchus nanus was the prevalent species among plant parasites at low infection level. Larvae of Globodera prevailed in the soil with middle and high infection levels and substituted individuals of other genera of parasitic nematodes. The fact of increase in number of hyphal-feeding nematode Aphelenchus avenae was revealed.

[Karyotypes of phytoparasitic nematodes of the genus Anguina Scopoli, 1799]. / O kariotipakh fitoparaziticheskikh nematod roda Anguina Scopoli, 1799.

Studies were carried out of karyotypes of Anguina sp. parasitic on four species of wild cereals and two species of sedge. The number of chromosomes in fissing genital cells was found to be n=9 for A. graminophila and n=18 for A. agrostis. Anguina sp. injuring sedge have the haploid number of chromosomes n=18.