First report of Oncastichus goughi in Israel
The EPPO Secretariat has recently been informed by the Israeli Plant Protection Service that a new pest, Oncastichus goughi has been found in Israel on wax flower plants (Chamelaucium uncinatum). O. goughi is a gall-forming wasp which attacks only wax flowers. The pest has been detected in one region only, in the central part of the country. Action is being taken in order to eradicate the pest or at least to prevent its spread.
The EPPO Secretariat has tried to find more information on this pest but very little data is available in the literature. In their paper, Redak ; Bethke (1995) explained that the major insect pest of Chamelaucium uncinatum is O. goughi which is a poorly studied gall-forming wasp. Economic damage due to this pest was originally reported from Australia in the mid-1980s. But the pest is now also present in California (US), as North American producers of C. uncinatum rely on Australian plant stock for the initial propagation of new varieties. O. goughi became established in California shortly after its discovery in Australia.
Adult female wasps lay eggs within the young leaf and stem tissues of the host plant. The eggs hatch and the larvae feed on the leaves and stems. In response to larval feeding, the plant forms an indeterminate "mark" type of gall around the area of initial oviposition and larval feeding. The gall enlarges as the larva feeds and grows. Galls will appear as simple swellings along young stems and the needle-like leaves ranging in size from 1.7 to 6.0 mm in length and from 1.0 to 1.9 mm in width. Pupation occurs inside the gall and adults emerge by a small emergence hole through the side of the gall. Mating, host-plant selection, and oviposition occur outside the gall. In Australia, the life cycle of the wasp lasts approximately 3 months with several complete generations per year. Gall formation renders the plants unmarketable. The authors have conducted studies on the use of traps and susceptibility of several cultivars. Field trials demonstrated that either yellow or green insect sticky traps could be used to catch adults, and that adult populations peaked during October and November. Four cultivars were examined during two years (White, Chinchilla, Vista, Lady Stephany); Lady Stephany was least susceptible to adult gall wasps, whereas the cultivar White was most susceptible.
Plant Protection Service of Israel, 1996-01
Redak, R.A. Bethke, J.A. (1995) Detection and seasonal occurrence of gall-forming wasps (Hymenoptera: Eulophidae) on geraldton wax plant.
Journal of Economic Entomology, 88(2), 387-392.