Center for Medical, Agricultural and Veterinary Entomology : 2002 Summer Employment Program Participants

Diamondback moth on a leaf.
The destructive diamondback moth.

Ryan Stype's project this summer was to determine if the predatory stink-bug Podisus maculiventris, and the parasitoid wasp Cotesia plutellae, act additively, antagonistically, or synergistically in efforts to control diamondback moth populations in cabbage.

A cabbage head growing in a field.
A healthy cabbage. A cabbage head, growing in a field, with heavy leaf damage.
A cabbage that has been largely devoured by diamondback moths.

Ryan Stype holding a watering can in a test plot.
Watering the test cabbages. Ryan Stype, bent over a cabbage in a test plot, holding back a leaf to check for insects.
Performing a meticulous inspection of each leaf on each cabbage.

Ryan's Abstract:

Interactions Between Podisus maculiventris (Say) (Heteroptera: Pentatomidae), Cotesia plutellae Kurdj. (Hymenoptera: Braconidae) and Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Cabbage

The diamondback moth, Plutella xylostella (L.), is the primary pest of brassicas in the southeast largely due to insecticide resistance. Biological control offers an alternate solution to insecticidal treatments. Furthermore, little is known of the interactions between predators and parasitoids that exploit the same resource. I am assisting in experiments testing if Podisus maculiventris and Cotesia plutellae have additive, antagonistic, or synergistic effects on diamondback moth populations in cabbage (Brassica oleracea var. capitata) by comparing moth populations and plant damage in replicated field cages containing 1) diamondback moth, 2) diamondback moth with P. maculiventris, 3) diamondback moth with C. plutellae, 4) diamondback moth with P. maculiventris and C. plutellae. These results will provide information addressing interactions between predators and parasitoids and alternate methods for suppression of diamondback moth populations in Florida.