LEVANTAMENTO DE FITONEMATOIDES E CARACTERIZAÇÃO BIOQUÍMICA DE POPULAÇÕES DE Meloidogyne spp. EM ÁREAS CULTIVADAS COM HORTALIÇAS NA REGIÃO SUL DO ESTADO DE GOIÁS

Abstract

The Goiás state stands out in the production of vegetables in the national context and its production is growing year after year. However, increased productivity and consequently production could be even higher if not for the nematodes attack mainly the galls trainers who are the ones that cause damage to vegetables. The producing areas of vegetables in Goiás are used intensively and submitted to monocultures with use of irrigation. This production system favors the multiplication of nematodes, with the great loss result because of their parasitism. In the state of Goiás, there are hardly any surveys of the occurrence of nematode populations in vegetables. Thus the present study aimed to carry out a survey and biochemical characterization of nematode galls in vegetable growing areas in the southern region of the State of Goiás. Sampling was conducted in 39 establishments with 68 samples collected, a total area of 62,1 hectares, during the years 2013-2015, covering 13 municipalities: Morrinhos, Piracanjuba, Goiatuba, Pontalina, Caldas Novas, Joviânia, Itumbiara, Água Limpa, Corumbaíba, Bom Jesus de Goiás, Buriti Alegre, Rio Quente and Marzagão. In each farm were sampled areas of different crops where several sub samples were taken to make a sample of soil and roots. In the samples that presented symptoms of nematode infection of galls held the biochemical characterization of species from isoenzyme (esterase phenotype) of females contained in the roots with galls. The samples were extracted from the soil nematode or roots and with the same suspension transferred to a slide and analyzed by light microscopy. The identification of gender was made with the help of nematode identification key. In all samples were found free-living nematodes and 33 samples were found phytoparasitic nematodes. The main genera were found Meloidogyne with 22%, Helicotylenchus with 19%, Tylenchus with 13%, Tylenchulus with 10%, Ditylenchulus, Rotylenchulus and Xiphinema with 6%, Pratylenchus, Hemicycliophora, Xiphidorus, Anguina, Tubixaba and Monotrichodorus with 3%. Of the 68 samples, 45 showed to be infected with root-knot nematode, which represented 66 % of the samples. 49% of the infected samples were identified as M. incognita, M. javanica 24% and 27% as Meloidogyne spp.. Approximately 34% of the samples were not infected by root-knot nematodes. Based on the results, it can be concluded that most of the areas cultivated with vegetables in the southern region of the State of Goiás, are infected with the nematode galls, particularly M. incognita. This study contributed to the knowledge of the occurrence and spread of Meloidogyne species that occur in areas cultivated with vegetables in southern Goiás. In addition to subsidizing new studies, service alert to horticulturists and allows you to define most suitable and efficient management strategies aimed at reducing the populations of nematodes in the infested areas.