DIAMONDBACK MOTH (LEPIDOPTERA, PLUTELLIDAE) INFESTATION AND PARASITISM BY DIADEAGMA INSULARE (HYMENOPTERA, ICHNEUMONIDAE) IN COLLARDS AND ADJACENT CABBAGE FIELDS

Two rows of collard greens (Brassica oleracea var. acephala L.) were p lanted between two cabbage fields in bunnell, Flagler County, Florida in spring 1995. More larvae of the diamondback moth (DBM), Plutella xy lostella (L.), were found on collard plants than on cabbage plants in the adjacent fields. The parasitism rate of DBM larvae collected from the collard plants reached 72% in early May and was higher than for la rvae collected from the cabbage plants in adjacent fields. Parasitoids recovered from DBM larvae were mainly Diadegma insulare (Cresson). Th e damage to collard plants caused by DBM larvae was greater than on ca bbage plants. At harvest, there was no significant difference in damag e ratings of cabbage heads sampled near the middle of the field and da mage to heads on rows nearest the collards. The results suggest that c ollard may have potential as a trap crop of DBM in cabbage fields, and that collard can play an important role in maintenance of the natural enemy, D. insulare.