THE IMPORTANCE OF PREDATORS IN CEREAL CROP AGROBIOCENOSIS IN LESKOVAC

The monocultural way of grain crop production may cause the massive emergence and development of both harmful and useful organisms in agrobiocenosis. Predators as natural enemies give a significant contribution to the reduction of pest population. The aim of the research was to monitor the biodiversity of predators and establish the differences in their faunistic composition, with regard to the agrobiocenosis of both spring and winter crops. The following standard entomological methods were used throughout the research: visual inspection, examination of above-ground parts of a plant, the sweep net method and laboratory processing of gathered material. The research was carried out from 2011 to 2013 on the experimental plot of the Agricultural High School in Leskovac. The research shows that the diversity maintenance and natural bioregulatory mechanisms are the basic rule in preservation of the grain agrobiocenosis against harmful insects. The predatory activities towards aphids were registered among the following five species of ladybirds belonging to the family of Coccinellidae: Coccinella septempunctata L., Adalia bipunctata L., Hippodamia variegata Goeze, Propylea quatourdecimpunctata L. and Calvia quatourdecimpunctata L. and 2 predators of family Chrysopidae: Chrysopa perla L. and Chrysopa carnea Steph. The research results showed similarity among ogranisms present in respective agrobiocenoses of spring and winter crops that were compared

EFEKAT ZALIVNOG REŽIMA U ZATVORENOM PROSTORU NA INTENZITET POJAVE PLAMENJAČE KRASTAVCA

Experimental research was conducted in Gracanica in 2019, on a commercial farm in a greenhouse. The variant treated with the fungicide Previcur Energy had on average the lowest infection rate of 0.5%. In the variant treated with the preparation Antracol WP-70, at an irrigation norm of 15 mm, an intensity of infection of 1.5% was recorded, while with an irrigation norm of 20 mm, the degree of infection was higher than 2.5%. The variant treated with the fungicide Folio Gold with a watering rate of 15 mm had an infection intensity of 1%, and with a watering rate of 20 mm a higher degree of infection was registered (2%). The variant with chemical protection with the fungicide Quadris was infected with an intensity of 1% on average.Publishe