Avaliação da resposta de espécies florestais do Cerrado a espécies virais dos gêneros Potyvirus e Tospovirus e estudos de caracterização de vírus em Mimosa caesalpinifolia

Abstract

The biodiversity of the Brazilian Cerrado is very large and forest species originating in this biome has great economic potential. These species, however, can be reservoirs of pathogenic viruses, responsible for major losses in many crops of agronomic interest. Thus, new information found in plants of this biome, referring to the interaction between pathogens and hosts, are of great importance, especially for knowledge of new host plant viruses, this information, rather scarce in the literature. Furthermore, these plants have potential for use in breeding programs via transgenesis, aiming resistance to plant pathogens. This study aimed to evaluate the type of response and the potential for some forest species as hosts of species of economically important virus genera. Potyvirus species (Potato virus Y-PVY) and Tospovirus (Groundnut ringspot virus - GRSV, and Tomato spotted wilt virus - TSWV) were mechanically inoculated via plant extract buffered. The tests were conducted at three different times using 22 tree species of the Cerrado. In the first and third tests were used seedlings from seed of 9 different species with two replicates for each species. In the second, fourth, fifth and sixth trials, seedlings from the FAL (Fazenda Água Limpa), and IV Viveiro NOVACAP another 13 species were used, each species with three replications. Were inoculated on two samples of each test species. As negative controls, we used samples from the same species, without inoculation. The tests were evaluated every 10 days. Virus detection was performed by symptoms and polyclonal antibodies by Dot-Blot. According to analysis, the samples in the laboratory, Chorisia speciosa, Ingas laurina, Lafoensia pacari and Schinus terebinthifolius were positive for GRSV; Chorisia speciosa, Hymenaea stignocarpa, Kielmeyra coreacea and Lafoensia pacari were positive for TSWV, and Eriotheca pubescens and Ingas laurina to PVY. Being Ingas laurina, Kielmeyera coreacea and Lafoensia pacari asymptomatic and Enterolobium gummiferum, Pterogyne nitens, Solanum lycocarpum and Tabebuia avellanedae only for symptomatic GRSV, GRSV, TSWV and PVY, respectively. At the end of this work were obtained 11 forest species as potential hosts of the viruses mentioned. They are: Chorisia speciosa, Enterolobium gummiferum, Eriotheca pubescens, Hymenaea stignocarpa, Ingas laurina, Kielmeyera coreacea, Pterogyne nitens, Lafoensia pacari, Schinus terebinthifolius, Solanum lycocarpum and Tabebuia avellanedae. It is with this that the Cerrado native plants and forest species of economic interest have great potential as a reservoir of virus, which may influence the distribution and maintenance of viral isolates of agronomic importance, which may in future also become important in the middle forest production. Moreover, it was possible to detect the species Begomovirus in Mimosa caesalpiniifolia, and the virus characterization studies are being conducted, presenting a job with great potential for further studies, mainly me taking account of the absence of studies characterizing viral in forest species.