ECOLOGICAL AND FAUNISTIC ARTHROPODS COMPLEXES OF MUSTARD AGROBIOCENOSES IN LOWER VOLGA REGION

Abstract

Results of long-term ecological and faunal researches of complexes of the arthropods living in the in agrocenoses of Brassica juncea (Sarepta mustard) in Lower Volga area are presented in article, the specifi c structure of insects – phytophages and entomophages is established, the structure of dominance and ecological structure of entomcenosis is defi ned. Researches of fauna of arthropods carried out during 1996-2015 systematically throughout all vegetation of Sarepta mustard with use of the standard methods.

In mustard agrocenosis of Lower Volga area as a result of our researches 108 species of insects – phytophages are revealed. The dominating specie in crops of mustard is Plutella maculipennis Curt. – 44.93% of the total number, subdominating – Phyllotreta sp. (14.10%), Meligethes aeneus L. (13.50%), Euridema sp. (12.92%) and Colaphellus hofti Men. (11.01%). Athalia colibri Christ. is least small – 3.53%. In mustard agrocenosis the Coleoptera group prevails by quantity of species of phytophages. It is established that in the conditions of Lower Volga area the greatest harm to Brassica juncea by Phyllotreta sp., Euridema festiva L., Colaphellus hofti Men., Plutella maculipennis Curt. And Athalia colibri Christ is done. The complex of mustard pests caused decrease in productivity of culture on average for years of researches for 31.6-56.2%. Leaf damages  decreased the content of aliphatic oil in seeds for 4.3%.

The greatest number of species of entomophages (84) falls into to Hymenoptera ordo; the Coleoptera includes 78 species, Diptera – 21 species, Hemiptera – 11. Several species presented ordos Neuroptera (3), Mantoptera (2), Orthoptera (2). As a part of entomocenosis of Sarepta mustard the entomophages from Hymenoptera ordo making 41.79% of all species of entomophages prevail. They are presented by 84 species from 13 families.

Phytophages and entomophages are most richly presented in the entomofaunistic communities – 314 species, or 82.4% of total of species are presented. The share of phytophages in mustard agrocenosis makes 27.03% of the common structure of entomocomplex. 55.38% of the revealed types in communities of insects – inhabitants of mustard agrocenosis belong to entomophages. Most variously as a part of the useful biota predatory insects – 130 species (34.12%) are presented.