Controle biológico (Glomus etunicatum), químico (fipronil) e estudo molecular (PCR-ITS) do nematóide do cisto da soja

Abstract

The studies of cist nematodes were evaluated in the greenhouse condition and in the Prof. Marcos Rubens Fries Environment and Soil Microbiology and Biology Laboratory, in the Soil Department of the Federal University of Santa Maria, in three stages. The first stage aimed to study through a survey of the presence of cyst nematodeos in soybean (NCS), in five counties, in Rio Grande do Sul state. The survey was carried out in eigth place with 28 samples with soybean culture. The counties were Espumoso, Eugênio de Castro, São Miguel das Missões and Tupanciretã. The soil samples had been processed in laboratory, and the NCS had been extracted by wet technique. It was detected presence of NCS in all five studied counties. The highest number of cysts was found in the counties of Espumoso and São Miguel das Missões. The second stage of the aimed to study the suppression of the NCS population using plants and to test the action of the fipronil on the egg hatching of NCS. Two experiments had been developed, the first with 10 treatments (without eggs of NCS and mycorrhizal, four treatments with diferents levels of eggs of NCS, 500, 1000, 2000 e 4000 eggs; with mycorrhizal; four treatment with mycorrhizal and eggs of NCS). In this experiment was observed that the presence of Glomus etunicatum fungi improved the plant grow. The study with fipronil showed significant reduction in hacthing when the eggs were exposed to the diferent concentrations of fipronil. It was observed, that the addition of small levels of fipronil can reduce the hatching in 50%. The third stage of the work was to evaluate the DNA characterization of the Heterodera glycines cists. It was obtained a good DNA extraction and experiments are carring out to do the PCR-ITS studies.