D. Blumberg et al., RESPONSE BY ENCAPSULATION OF 4 MEALYBUG SPECIES (HOMOPTERA, PSEUDOCOCCIDAE) TO PARASITIZATION BY ANAGYRUS-PSEUDOCOCCI, Phytoparasitica, 23(2), 1995, pp. 157-163
The frequency of encapsulatio of eggs of Anagyrus pseudococci (Girault
) (Hymenoptera: Encyrtidae) by four mealybug species: Planococcus citr
i (Risso), Pl. vovae (Nasonov), Pl. ficus (Signoret) and Pseudococcus
cryptus Hempel (=citriculus Green), was studied under controlled labor
atory conditions. The aggregate percentage of encapsulated eggs (AE) a
nd the percentage of efficient encapsulation (EE) (= percent parasitiz
ed mealybugs wherein encapsulation prevented the development of all pa
rasitoid larvae) by Pl. citri and Pl. vovae did not differ significant
ly (39.0% vs 38.2% AE and 15.4% vs 17.6% EE, respectively), but was si
gnificantly higher than in Ps. cryptus (16.2% AE and 5.4% EE). Encapsu
lation by Pl. vovae was significantly higher than by Pl. ficus (38.2%
vs 20.1% AE and 17.6% vs 7.7% EE, respectively). Neither the host plan
t nor the rearing temperature significantly affected the incidence of
parasitoid encapsulation. It is suggested that A. pseudococci displays
a relatively low physiological adaptation to Pl. citri; thus, in a ci
trus grove, for example, ca 40% of the parasitoid egges might be lost
due to encapsulation. The question of a possible association between e
ncapsulation and host-parasitoid relationships among the mealybugs stu
died and A. pseudococci, is discussed.