Reproductive biology of Biosteres vandenboschi (Hymenoptera: Braconidae), a parasitoid of early-instar Oriental fruit fly

Some aspects of the reproductive biology of Biosteres vandenboschi (Fullaway) were investigated in the laboratory. Mean longevity of host-deprived and ovipositing females was 28.6 and 23.7 d, respectively. In parasitoid stock reared from Ceratitis capitata (Wiedemann), newly emerged B. vandenboschi had a mean of 4.2 mature ovarian eggs, and ovarian maturation peaked at 41.2 eggs on the 12th d after eclosion. However, B. vandenboschi reared from Bactrocera dorsalis (Hendel) had an earlier peak on the 6th d after eclosion and a similar one on the 12th d. Mean numbers of mature ovarian eggs declined, as age of female increased in both parasitoid stocks. Overall mean mature ovarian eggs of host-deprived females eclosed from B. dorsalis was significantly higher than overall mean ovarian eggs of females eclosed from C. capitata. Despite the availability of abundant hosts suitable for oviposition, female B. vandenboschi reared individually were reluctant to deposit many eggs. Average egg deposition per day was only 16% of the ovarian eggs available, and average potential fecundity (eggs laid by a female plus eggs remaining in ovaries at death) was 65 eggs in both mated and unmated females. Potential fecundity in ovipositing females was 1.9-fold higher than the maximal number of ovarian eggs found, an indication of significant enhancement of egg maturation by oviposition activity. Second and early third instars of B. dorsalis, when presented to B. vandenboschi for oviposition, produced significantly higher female offspring than female offspring produced from first-instar B. dorsalis. The number of uneclosed host puparia was reduced when second-instar B. dorsalis were exposed for oviposition.