Biocontrol introduction
Target pest: Helicoverpa armigera (Lepidoptera: Noctuidae), tomato fruitworm
Agent introduced: Cotesia kazak (Hymenoptera: Braconidae) = Apanteles kazak
Imported:
1977
Import source:
Bulgaria and Greece
Import notes:
Cameron et al. (1989) - Cotesia kazak was collected from Helicoverpa amigera in Bulgaria and Greece by the Commonwealth Institute of Biological Control and reared on Heliothis virescens for shipment to New Zealand in 1977.
Released:
1978
Release details:
Cameron et al. (1989) - approximately 3,500 adults or parasitised larvae were released over two seasons from 1978 to 1980 at 30 sites in Northland, Auckland, Bay of Plenty and Gisborne in the North Island. It was redistributed to Marlborough in the South Island in 1985 through the release of 85 cocoons at one lucerne site.
Establishment:
Cameron et al. (1989) - widely established in vicinity of all North Island release sites by 1982. Natural dispersal of approximately 100 km per year has spread the C. kazak to Waikato and Hawke’s Bay but not to Manawatu. Recoveries from four sites in Marlborough in 1987 indicate the parasitoid has established there.
Impacts on target:
Cameron et al. (1989) - by 1986 parasitism rates frequently exceeded 60%, resulting in fewer H. armigera larvae reaching damaging size and a reduction in crop damage. However, this parasitoid is not sufficient on its own to eliminate economic damage by H. armigera in unsprayed crops and the introduction of further biocontrol agents is warranted.
Cameron et al. (1993) - Cotesia kazak, in conjunction with Microplitis croceipes [see the M. croceipes introduction entry], is categorised as exerting “partial” control (defined as “additional control remains commonly necessary but…pest outbreaks occur less frequently”) over Helicoverpa armigera.
References
Cameron PJ, Hill RL, Bain J, Thomas WP (1989). A Review of Biological Control of Invertebrate Pests and Weeds in New Zealand 1874-1987. Technical Communication No 10. CAB International Institute of Biological Control. DSIR Entomology Division. 424p.
Cameron PJ, Hill RL, Bain J, Thomas WP (1993). Analysis of importations for biological control of insect pests and weeds in New Zealand. Biocontrol Science and Technology 3(4): 387-404
