EXTRAFLORAL NECTAR, HONEYDEW, AND SUCROSE EFFECTS ON SEARCHING BEHAVIOR AND EFFICIENCY OF MICROPLITIS-CROCEIPES (HYMENOPTERA, BRACONIDAE) IN COTTON

The influence of extrafloral nectar, sucrose, or whitefly honeydew on host- and food-searching behavior of Microplitis croceipes (Cresson) f emales was investigated. Retention time, parasitization rate, time all ocation to host damaged leaves and time interval between subsequent ho st attacks were compared in different cotton, Gossypium hirsutum L., p atch treatments containing Heliocooerpa tea (Boddie) hosts. Parasitoid s that were starved for 2 d before release to patches with either sucr ose or extrafloral nectar showed longer retention times and higher rat es of parasitization than those not able to feed. The presence of food in the patch increased the time allocated to damaged leaves, but did not reduce the time interval between most attacks. Parasitoids that fe d in patches with honeydew showed a similar performance to parasitoids in patches without any food, probably as a result of the relatively l ow quantity and quality of this food source for M. croceipes. The init ial and subsequent detectability of different food sources was also in vestigated. More parasitoids found extrafloral nectar than sucrose in a first release. However, in a subsequent release, nectar and sucrose were found equally fast. Therefore, parasitoids showed an innate attra ction to extrafloral nectar, whereas learning may have influenced orie ntation to sucrose. The importance and use of cotton extrafloral necta r as food source for adult parasitoids and the means of using extraflo ral nectar as part of a pest management strategy in biological control are discussed.