Evaluation of the effects of fipronil, 2,4-D and their mixtures on the interactions between predators and prey of neotropical aquatic biota

Abstract

The growth of agricultural systems in Brazil has as a consequence the increase in the use of pesticides, making the country the largest consumer in the world of these compounds. The indiscriminate use of these substances is a cause for socio-environmental concern since there are related problems from biodiversity loss to public health risks. In southeastern Brazil, the region where the highest sugarcane production occurs of the country, we highlight the use in these monocultures of the insecticide Regent® 800 WG, whose active ingredient is fipronil, and the herbicide DMA® 806 BR, which has as active ingredient the 2,4-D. In front of the presented, the problem that surrounds the use of these pesticides and their effects on non-target autochthonous organisms of contaminated environments and consequences ecosystems is imminent. It is known that predation plays an important role in maintaining the structure and functioning of ecosystems, however, few studies have been conducted so far to evaluate this interaction in scenarios where pollution is present. For this, the present project initially, is willing to analyze the acute toxicity of fipronil and 2,4-D pesticides isolated and in mixtures on the species Tramea cophysa (Libellulidae, Odonata) and Belostoma sp. (Bellostomatidade, Hemiptera). Subsequently, the effects of pesticides isolated and in mixtures will be analyzed, on the feed rate, feed preference and swimming behavior of the species T. cophysa and Belostoma sp. in laboratory toxicity tests. The food preference will be evaluated by offering different prey for these predator species. As a consequence, it is hoped that the study may aid in increasing our understanding of food chain mechanisms underlying chemical stress.