Relatively few studies have examined predation of Empoasca fabae (Harris) (Hemiptera: Cicadellidae), an important insect pest of alfalfa (Medicago sativa L. [Fabaceae]). In this laboratory study, we quantified rates at which E. fabae adults and nymphs were attacked by three predatory species: Coleomegilla maculata (Degeer) (Coleoptera: Coccinellidae), Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), and Orius insidiosus (Say) (Hemiptera: Anthocoridae). Individual predators and E. fabae were held in a feeding arena for 24 hours (individual fava bean plants [Vicia faba L. (Fabaceae)] enclosed within dialysis tubing). Adult C. maculata attacked 4.2 nymphs and 1.6 adults at the high-prey density (15 E. fabae nymphs or 10 adults per cage) and 2.0 nymphs and 0.6 adults at the low-prey density (5 E. fabae nymphs or 3 adults per cage). Orius insidiosus attacked twice as many E. fabae nymphs than adults at the high density (2.9 versus 1.2). In contrast, similar numbers of nymphal and adult E. fabae were attacked by C. carnea larvae (4.6 versus 3.5, 1.2 versus 0.8; at high - and low-prey densities, respectively). Of the three predatory species, C. carnea larvae attacked the most E. fabae nymphs and adults. These predatory species may play a role in maintaining low population densities of E. fabae in alfalfa.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 83 • No. 1