Amostragem e efeito da vinhaça sobre a distribuição de nematóides associados à cana-de-açúcar em áreas de encosta e tabuleiro da mata norte de Pernambuco

Detalhes bibliográficos
Ano de defesa: 2010
Autor(a) principal: MATOS, Daniela Silva Salgues de lattes
Orientador(a): PEDROSA, Elvira Maria Régis
Banca de defesa: OLIVEIRA, Sônia Maria Alves de, GUIMARÃES, Lílian Margarete Paes, SANTOS, Carolina Etienne de Rosário e Silva, CAVALCANTE, Uided Maaze Tibúrcio
Tipo de documento: Tese
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal Rural de Pernambuco
Programa de Pós-Graduação: Programa de Pós-Graduação em Fitopatologia
Departamento: Departamento de Agronomia
País: Brasil
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6497
Resumo: In Northeastern Brazil the root-knot (Meloidogyne spp.) and lesion (Pratylenchus zeae) nematodes are important plant pathogens in sugarcane growing areas, causing damage higher than 20% of production. Several control measures are recommended for nematode control, however none of them is effective enough in decreasing initial population density and avoiding environmental risks. Adequate sampling would improve nematode management and reduce costs. On the other hand, the vinasse application has been frequently emphasize because of the high residue amount from sugarcane industrialization and high pollution from excessive oxygen demand. The objectives of the present study were to evaluate in costal table and lean areas effects of the sugarcane irrigation with vinasse on nematode communities and chemical atributes of soil, correlating effects among variables analyzed and sampling net; indicate sample number for monitoring Meloidogyne spp. and P. zeae and characterize the spatial variability of these nematodes in costal table irrigated with vinasse. The experiments were carried out in costal table and lean areas cultivated with sugarcane irrigated and non irrigated with vinasse. Soil samples were collected 25-cm deep in 1×1, 10×10 and 50×50-m square net samplings, with 36 points each, in a total area of 25 m2, 2,500 m2 and 62,500 m2, respectively. Techniques of descriptive statistics and geostatistics were applied for characterize the magnitude of spatial dependence of nematode distribution.In order to provide data for an adequate disease management in the area, it was drawn krigagen maps of nematodes spatial distribution. In general, nematode population dynamic depended on vinasse application and chemical characteristics of the soil. In coastal tables, phosphorus, calcium and cation concentration significantly correlated with plant parasite nematodes (r = -0.17, 0.17 and 0.16) and total nematodes (r = -0.20, 0.21, 0.17), respectively. In lean lands there was negative correlation between magnesium and plant parasitic nematodes (r = -0.16). Total amount of nematode in irrigated area was lower than in non irrigated one. Ten up to 75 and 12 up to 40 soil and root samples, respectively, were indicated for monitoring P. zeae depending on sampling net. For Meloidogyne spp. the number of samples ranged from 34 to 132 and 13 to 117 for soil and root, respectively, depending on sampling net. According to semivariograms, Meloidogyne spp. presented moderate and strong spatial dependence in 1×1 and 50×50-m net, respectively, and P. zeae moderate spatial dependence in both nets. The Gaussian model best fitted Meloidogyne spp. in 1×1-m net and P. zeae in both 1×1 and 50×50-m net. For Meloidogyne spp. in 50×50-m net the exponential model fitted the best. In 10×10-m net there was pure nugget effect model for both nematodes.