LABORATORY TESTS TO COMPARE THE PREDATORY VALUE OF SIX MIRID SPECIES IN EACH STAGE OF DEVELOPMENT AGAINST THE WINTER EGGS OF THE EUROPEAN RED MITE, PANONYCHUS ULMI (ACARI: TETRANYCHIDAE)

Abstract

AbstractSix species of predacious Miridae, common to apple trees in Nova Scotia, were used to develop laboratory rearing and feeding techniques for comparing the abilities of predators to consume prey. The test prey species was the European red mite, Panonychus ulmi (Koch), in the winter egg stage. The numbers of eggs consumed per day and per instar in the tests compared favourably with the known predatory values of these mirids under orchard conditions. Both sources of information were used to give the predators a tentative rating. The mirids Hyaliodes harti Knight, Diaphnocoris pellucida (Uhler), Pilophorus perplexus D. and S., and Blepharidopterus angulatus (Fall.) are effective predators, approximately equal to each other in ability to consume the winter eggs of the red mite. The two species Campylomma verbasci (Meyer) and Atractotomus mali (Meyer), which are phytophagous as well as predacious, were less voracious.The results indicate it may be feasible to develop a series of weighting factors, one for each stage of each predacious species, based on ability to consume prey.