Toxicidade de extratos vegetais ao percevejo bronzeado do eucalipto Thaumastocoris peregrinus (hemiptera: heteroptera: thaumastocoridae) e organismos não-alvo

Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae ) is an insect from Australia which is causing severe damage to eucalyptus crops around the world. When feeding from the leaves sap, it causes bronzening, and in extreme cases, may lead to the tree death. Control methods have been studied and the most promising so far is the egg parasitoid Cleruchoides noackae (Hymenoptera: Mymaridae). Alternative products from plants with insecticidal properties could also be a viable option, and they might even be used concomitantly with C. noackae, aiming for a most effective control, but still safe for the environment. Thus, the objective of this work was to verify the action of 5% aqueous plant extracts of Matricaria chamomilla, Echinodorus grandiflorus, Punica granatum, Maytenus ilicifolia a n d Origanum majorana on T. peregrinus. In addition, we aimed to study the extracts potential toxicity to C. noackae and Gallus domesticus L., since the plant compounds might have negative effect upon the non-target organisms. At first, HPLC (High Performance Liquid Chromatography) was used to verify which phenolic compounds would be found in the plant extracts. These were tested on bronze bug adults, in confinement test (to verify the insecticidal action of the extracts) and free-choice test (to verify the repellency). The extracts that showed better results were selected for further tests with non-target organisms. Regarding C. noackae, pre-parasitism and post-parasitism, confinement and free-choice tests were performed to verify if the extracts would affect the host-choosing by the female or the development of the immature stages of the parasitoid. To verify if the extracts would be toxic to G. domesticus, the plant extracts were added to young birds feed for five days. Parameters such as weight gain, food intake, quantification of serum enzymes and histopathological analysis were carried out. HPLC analysis detected gallic, ferulic, vanillic, caffeic and cumaric acid in the extracts samples. All plant extracts tested reduced T. peregrinus survival, but E. grandiflorus, Matricaria chamomilla Maytenus ilicifolia had also a repellent effect, and were tested on the non-target organisms. None of these extracts affected neither the host choice by C. noackae nor adult emergency, when compared to the control group. In addition, the extracts did not cause alterations in any of the studied parameters. Thus, we verified that E. grandiflorus, Matricaria chamomilla and Maytenus ilicifolia have potential to be used to control T. peregrinus and are safe to C. noackae and G. domesticus.

Macrofauna epígea de besouros coprófilos em sistema de integração lavoura-pecuária

The soil macrofauna (organisms ≥ 2.0 mm) main function is to act indirectly on the decomposition of organic matter and control the population of microorganisms. This study aims to evaluate the density and richness of coprphilic dung beetles at different levels of nitrogen fertilization and grazing pressure on Crop-Livestock Integration System (ILP) and his opposition to morphotypes present in the native forests of the region. Was used a rural area in Abelardo Luz city, western state of Santa Catarina, on the border of southwest of Paraná, 26° 31' 18.8832" south latitude and 52° 15' 3.4986' west longitude and elevation 862 m for the installation of the experiment, which is already carried out the activity of agriculture and livestock. The study is part of the Integrated Project of Long Duration GISPA UTFPR Group, which evaluates the grazing pressure and time of fertilization deployed in April 2013. The experimental design was a randomized complete block design in a 2x2 factorial arrangement with three replications. The factors were "Nitrogen Application" (NP = N in the pasture and NG = N applied in corn) and "Height Grazing" (high and low). The native forest, which provided the parameters for assessing the degree of conservation, lies 700 meters northeast of the experimental area. Modified pitfall traps were used at ground level, on the bait trap and covered together to prevent dehydration. They were carried out 36 collections in bushland, within one year from 26 April 2013, in which we obtained a total of 16,301 individuals and 28 morphotypes. In ILP area specimens were collected from June to September 2014, totaling 23 collections, 74,586 individuals and 30 morphotypes. To carry out the statistics and faunal analysis, GENES programs were used, ANAFAU, NTIA/EMBRAPA and SigmaPlot version 12.5. Most of the correlations observed (90%) between the variables of insects and environmental conditions was significant. The largest number of insects was directly related to the temperature rise. There was a positive correlation between the application of nitrogen and the occurrence of coprophilous. There was a positive correlation between the number of insects and low grazing height. It was also found that some of the insects migrate from the culture to the area of native forest after reaching their peak population. The great similarity of results observed in the native forest and the ILP System indicates the ecological benefits of adopting this technology.