Evaluation of potential food sources for development by three species of picture-winged fly (Diptera: Ulidiidae) corn pests

A small group of picture-winged fly species (Diptera: Ulidiidae) are crop pests. Three of these, Euxesta eluta Loew, E. stigmatias Loew, and Chaetopsis massyla (Walker) have been reared from corn ears collected from across the southeastern U.S. However, corn is not available year round to support these species. Laboratory studies were conducted to evaluate other crop and non-crop plants for their potential as ovipositional and developmental hosts of these species. Locally available vegetables, fruits and weeds were exposed to flies under no choice conditions for 24 h and then held for further development of fly eggs. Larval period, pupal period, number of pupae and number of adults emerged were recorded. Larvae of E. eluta developed faster than the other species in all the commodities evaluated. Larval periods of E. stigmatias and C. massyla were dependent on the commodity involved. Inconsistent differences were found in the length of pupal periods of the three species. The number of pupae of each of the fly species reared from tested hosts followed the order bellpepper (Capsicum annum) > cabbage (Brassica oleracea) > tomato (Lycopersicon esculentum) > papaya (Carica papaya) > hass avocado (Persea Americana) > radish (Raphanus sativus) > sugarcane (Saccharum officinarum) > habanero (Capsicum chinense) > little hogweed (Portulaca oleracea) > spiny amaranth (Amaranthus spinosus). Together with field survey results, information on alternative food hosts will be beneficial in understanding the population dynamics leading to better management of these flies.