FURTHER-STUDIES OF THE ENCAPSULATION OF EGGS OF METAPHYCUS SPP (HYM, ENCYRTIDAE) BY THE PYRIFORM SCALE, PROTOPULVINARIA-PYRIFORMIS (HOM, COCCIDAE)

The encapsulation of eggs of Metaphycus swirskii Annecke & Mynhardt (H ymenoptera: Encyrtidae) by the pyriform scale, Protopulvinaria pyrifor mis (Cockerell) (Homoptera : Coccidae), collected in the coastal plain of Israel, was determined during April 1986 to May 1987. The rates of encapsulation were low in November (13.0 %) and relatively high in Ap ril, May, August and September (32.0-89.0 %). The seasonal variations in the encapsulation of eggs of M. stanleyi Compere and/or M. swirskii by P. pyriformis infesting avocado (Persea americana) and jambolan (S yzygium cumini) were studied at Miqwe Yisra'el (coastal plain) during October 1986 to February 1988. Encapsulation rates were similar in sca les infesting either of the two host plants. They were highest during July to August (49.0-75.0 %) and lowest during December to February (0 .9-10.0 %). Encapsulation incidence at Miqwe Yisra'el was correlated w ith the ambient temperatures (r = 0.89). The rate of encapsulation of parasitoid eggs (M. stanleyi and/or M. galbus Annecke) recorded in P. pyriformis sent to Israel from Spain in September 1987 was 42.2 %. The high rates of encapsulation of Metaphycus spp. eggs by P. pyriformis during the summer, may interfere with efficient biological control of the pest.