*3.2.6 Aphidophagous hoverflies*

Moerkens et al. [31] investigated the potential of hoverflies *Eupeodes corollae* and *Sphaerophoria rueppellii* to manage foxglove aphid *Aulacorthum solani* in sweet pepper. In a semi-field study, aphid numbers were significantly lower in the *E. corollae* and *S. rueppellii* treatments than in control. The fruit yield and seed set were also increased for *E. corollae* and *S. rueppellii*.

*Major Pests and Pest Management Strategies in the Sweet Pepper (*Capsicum annuum*) DOI: http://dx.doi.org/10.5772/intechopen.106386*

## **3.3 Parasitoids**

Most parasitoids developed for biological control belong to the family Aphelinidae. These parasitoids are tiny wasps and have been used to control the whitefly [32]. For instance, *Encarsia formosa* is a parasitoid used worldwide for the biological control of whiteflies attacking various vegetables such as sweet pepper cultivated in greenhouses. It lays eggs into hosts and causes a reduction of hosts. Uses of *E. formosa* are well known for controlling whiteflies because of the following factors. Whitefly population growth is reduced when *E. formosa'*s intrinsic rate of increase is greater than the host's intrinsic in the presence of parasitoids. This situation has resulted when host plants facilitate parasitoid searching and exhibit partial resistance to whitefly development. Additionally, giving-up time on infested leaves increases when hosts or host products are located, increasing the likelihood that parasitoids will encounter suitable hosts in a patch. It was also reported that spatial refuges for whiteflies from parasitoids exist in large greenhouses (greater than 1000 m<sup>2</sup> ) and consequently promote stable host or parasitoid dynamics [32].
