Adult survival of Orius strigicollis (Poppius) on different flowering plants and its development and fecundity on buckwheat flowers

Abstract

In conservation biological control programs, cultivation of flowering plants around/in agricultural fields is considered to be an effective approach to enhance predatory activity of natural enemies by providing their foods, refuges and oviposition sites. The minute pirate bug, Orius strigicollis, is an omnivorous predator and is used as an important biological control agent against thrips pests in Japan. However, little is known about the insectary plants available for O. strigicollis. Here, we investigated the longevity of O. strigicollis adults maintained on flowers and leaves of 10 plant species. In all tested plants except for French marigold, the predators fed on flowers survived longer than those fed on leaves of the same plants. In particular, flowers of buckwheat, coriander, dill, fairy-fan flower, holly basil, sweet alyssum and vervain increased longevity of O. strigicollis by four fold or more than the corresponding leaves. However, survival rate of O. strigicollis nymphs and the number of eggs deposited by female adults on buckwheat flowers was lower than those fed on Mediterranean flour moth eggs. Based on these results, we discussed possibilities of flowering plants serving as food resources for O. strigicollis in the field.