Soil entomofauna of the agrobiocenosis of a wheat field in the Central Forest-Steppe zone of Ukraine

Abstract

The purpose of the article is to clarify the species compositionof soil insects in the winter wheat agrocenosis ofthe Forest-Steppe of Ukraine. Identification of dominantspecies, their food specialization. Analysis of the state of populations and obtaining information about their numbersto make a forecast regarding the need for chemicalprotective measures. Research methods and materials.The research was conducted during 2019-2024 on winterwheat crops located in the Obukhiv (2023-2024) and BilaTserkva districts of the Kyiv region. The research was conductedusing generally accepted entomological methods:soil excavation, survey of registration sites, mowing withan entomological net, theoretical (proposing a hypothesisand forming conclusions based on research results;statistical; mathematical). Results. During the study ofthe entomocomplex of the surface layer of the soil of thewheat field, a small number of beetles from the families:black beetles (Tenebrionidae), weevils (Curculionidae),the number of which was insignificant. Among theLepidoptera, the winter moth (Agrotis segetum Schiff.(family Noctuidae) was dominated, as well as caterpillarsand other gnawing beetles, were found in the collections.They caused minor damage to young plants. Their densitywas 1,3 individuals/m2. Puparia and larvae of the wheatfly (Phorbia secures Tiensum.), the sprout fly (Delia platura(Migen.), and the winter fly Leptochylemyia coarctataF. (order Diptera, family Anthomyidae) were found inwinter wheat fields. The proportion of representatives ofall other insect orders was much smaller and amountedto 2% in total. Conclusions. The soil entomofauna ofthe winter wheat agrocenosis consisted of polyphagousinsects. Mostly representatives of the order Coleoptera,Lepidoptera, and Diptera. Among the coleopteran pests,small grain beetle larvae (Zabrus tenebriodes Goeze.),wireworm larvae (Elateridae) and scarab beetle larvae(Scarabaeidae) were found in small numbers, the densityof which was 2,6 individuals per m2 and 0,76 individualsper m2, respectively, which does not exceed the threshold.Among the Lepidoptera, the winter moth (Agrotis segetumSchiff. (family Noctuidae) dominated, its larvae and othergnawing moths caused minor damage to young plants.Their density was 1,3 individuals/m2. In isolated samples,pupae and larvae of the wheat fly (Phorbia securesTiensum.), the sprout fly (Delia platura (Migen.), and thewinter fly (Leptochylemyia coarctata F. (order Diptera,family Anthomyidae) were detected. Among the beneficialinsects, the most numerous was the hairy ground beetle(Harpalus rufipes Deg). Although it feeds on mixed food,but no damage to wheat plants was noted. Staphylinidaewere also found in small numbers. The adults and larvaeare saprophytes, and some species are active entomophagous.According to research results, outbreaks ofharmful soil entomofauna species in the Forest-Steppe ofUkraine on winter wheat are not expected. Therefore, inthe near future, it is not advisable to use chemical measuresto protect winter wheat crops aimed at soil pests.