REPRODUCTIVE-BIOLOGY AND BEHAVIOR OF A THELYTOCOUS SPECIES OF ERETMOCERUS (HYMENOPTERA, APHELINIDAE) PARASITIZING BEMISIA-ARGENTIFOLII (HOMOPTERA, ALEYRODIDAE)
Hj. Mcauslane et R. Nguyen, REPRODUCTIVE-BIOLOGY AND BEHAVIOR OF A THELYTOCOUS SPECIES OF ERETMOCERUS (HYMENOPTERA, APHELINIDAE) PARASITIZING BEMISIA-ARGENTIFOLII (HOMOPTERA, ALEYRODIDAE), Annals of the Entomological Society of America, 89(5), 1996, pp. 686-693
Eretmocerus sp., a thelytokous aphelinid parasitoid of Bemisia argenti
folii Bellows & Perring, was imported into the United States from Hong
Kong in June 1992. We investigated the foraging behavior and reproduc
tive biology of this species as part of an evaluation of its potential
for biological control of B. argentifolii. Parasitoids performed ster
eotyped behaviors upon encountering whitefly hosts, including antennat
ion, circle-antennation, probing, postprobing host tapping, and host f
eeding. During 1-h videorecording periods, parasitoids were observed t
o accept all whitefly instars for host feeding and oviposition. After
confining parasitoids for 24 h with whitefly nymphs, significantly mor
e eggs were found under end and 3rd instars than under Ist and 4th ins
tars. Parasitoids fed honey, with no access to whitefly nymphs, lived
significantly longer (12.5 d) than those given access to nymphs, but n
o honey (8.4 d). Lifetime fecundity averaged 92.8 female progeny per f
emale, ranging from 3 to 147. Daily fecundity, measured as the number
of whitefly nymphs parasitized per female each day for 9 d, averaged 2
0 for the first 6 d of life, and then declined to <10. On average, 4.5
nymphs were fed on by parasitoids each day during the first 3 d of li
fe. Developmental period from oviposition to parasitoid emergence was
significantly shorter in 3rd instars of tile host (16.4 d), than in 2n
d (16.8 d) or Ist instars (17.6 d).