CONTROL OF PHYTOPHAGOUS APHIDS IN URBAN GREEN SPACES THROUGH ENVIRONMENTALLY FRIENDLY WAYS

Abstract

Aphids have grown significantly both in number of species and in number of individuals in populations, especially in green spaces in urban environments. By feeding, they affect the plants in the structure of the ecosystem at the foliar and floral level, therefore it is necessary to manage them so that they are numerically reduced but at the same time to avoid the application of pesticides. Through this work, 2 ways of management were tried for 5 months (April-August): by exploiting existing natural enemies and by using sticky traps. The 4 study sites in western Romania (Timi?oara city) consisted of green spaces composed of various mixtures of ornamental plants, usually shrubs and trees of different species. As a result, 4 aphid species (Macrosiphum rosae, Aphis gossypii, Aphis pomi and Myzus cerasi) were identified whose populations had high values (x= 468.7-1246.5) and which were considered as the target organism in the study. The effectiveness of the most common natural enemies (beetles, syrphids and parasitic wasps) was analyzed and yellow sticky traps were placed for dual-role capture (aphid detection and their immortalization). It was found that both methods are effective, the harmful insects being visibly reduced compared to the initial value. Natural enemies vs. phytophagous aphids had a good effectiveness ratio (1:18.25), while colored sticky traps retained and killed 78% of captured aphids. The management of aphids in the agro-horticultural spaces between people's homes, although it seems difficult to achieve, we consider that it can be done within reasonable limits through non-pheromonal traps and existing natural enemies, somehow keeping the harmful populations under control and not affecting humans and the environment.