Conservation of Non-Pest Whiteflies and Natural Enemies of the Cabbage Whitefly <i>Aleyrodes proletella</i> on Perennial Plants for Use in Non-Crop Habitats

• Main Authors: Sebastian Laurenz, Rainer Meyhöfer
• Format: Article
• Language: English
• Published: MDPI AG 2021-08-01
• Series: Insects
• Subjects: <i>Aleyrodes lonicerae</i>; <i>Encarsia tricolor</i>; alternative host/prey; conservation biological control; field margin; functional biodiversity
• Online Access: https://www.mdpi.com/2075-4450/12/9/774

<i>Aleyrodes proletella</i> causes severe economic damage to several <i>Brassica</i> crops. Its naturally occurring enemies often immigrate late in the season or appear in low numbers on cabbage. This field study aims to permanently increase the local abundance of <i>A. proletella</i>’s natural enemies by providing the non-pest whitefly <i>Aleyrodes lonicerae</i> as an alternative and overwintering host/prey. Therefore, the population dynamics of natural enemies on different perennial herbaceous plants pre-infested with <i>A. lonicerae</i> were determined at two field locations over two winter periods. Most <i>A. lonicerae</i> colonized (on average 166.22 puparia per m²) and overwintered (342.19 adults per m²) on wood avens <i>Geum urbanum</i>. Furthermore, the abundance of <i>A. proletella</i> main parasitoid <i>Encarsia tricolor</i> (28.50 parasitized puparia per m²) and spiders (12.13 per m²) was 3–74 times and 3–14 times higher, respectively, on <i>G. urbanum</i> compared to the other experimental plants. Conclusively, <i>G. urbanum</i> pre-infested with <i>A. lonicerae</i> permanently promoted natural enemies of <i>A. proletella</i> by serving as shelter, reproduction, and overwintering habitat. A potential implementation of <i>G. urbanum</i> in conservation biological control strategies (e.g., tailored flower strips, hedgerows) against <i>A. proletella</i> are discussed and suggestions for future research are given.