Potencial de extratos aquosos de plantas da caatinga sobre o ácaro verde da mandioca Mononychellus tanajoa Bondar (Acari: Tetranychidae)

Detalhes bibliográficos
Autor(a) principal: SIQUEIRA, Felipe Fernando da Silva
Data de Publicação: 2013
Tipo de documento: Dissertação
Idioma: por
Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6156
Resumo: The green mite, Mononychellus tanajoa Bondar (Acari: Tetranychidae), is a pest of considerable economic importance for cassava in Brazil, with a wide distribution in South America and in some African countries, due to abiotic conditions (high temperature, relative humidity low), which favor their infestation. The acaricides have been used in its control due to the low technological level of culture that does not compensate for the use of these inputs, as well as the possible side effects caused to applicators, wildlife and the environment. For these reasons, efforts are being made in the search for natural compounds with insecticidal properties and/or miticides. Thus, the present work aimed evaluates the acaricidal activity and repellency of aqueous extracts isolated from plants of the Caatinga Serra Talhada, Pernambuco, to M. tanajoa. The aqueous extracts Croton blanchetianus, Myracrodruon urundeuva, Ziziphus joazeiro were investigated using the immersion technique of cassava leaf disks (3.5 cm diameter) in the tails of the products at the concentrations of 1, 5, 10, 15, 20 and 25%. One evaluated the effects of sublethal extracts using the instantaneous rate of increase (ri) of the population of M. tanajoa, mortality and repellency of adult females. The population growth of M. tanajoa in cassava leaf disks was affected by the aqueous extracts of C. blanchetianus, M. urundeuva and Z. joazeiro at all concentrations tested (1, 5, 10, 15, 20 and 25%), which showed population decline. Just control showed population growth in the ascendancy. Concentrations of 20 and 25% of the extracts showed higher mortality, the most promising for pest control. Furthermore, all concentrations of the extracts showed repellent effect. According to the literature, this is the first recorded use of the extracts of these plants for the control of M. tanajoa.