Avaliação da diversidade de plantas espontâneas e a densidade de ácaros predadores em cultivo de pinhão-manso Assessment of the diversity of spontaneous plants and the density of predaceous mites in a physic nut crop

The spontaneous vegetation has important ecological functions for agroecosystems, especially in the provision of resources for the maintenance of natural enemies. The aim of this work is to evaluate the diversity of weeds and temporal distribution of predatory mites associated with the culture of physic nut and weeds. In an area of 0.5 ha of samples were taken monthly from February 2010 to January 2011, both of predatory mites on weeds as on physic nut, in addition to estimating the index Shannon- Wiener diversity for weeds. The diversity of plants by the Shannon-Wiener index was significantly correlated with the density of predatory mites, directly influencing the occurrence of natural enemies in the agroecosystem.