Biological control of Listronotus bonariensis in New Zealand
In New Zealand, Listronotus bonariensis (EPPO A1 quarantine pest) is a serious pest of grasslands. Although losses have been estimated between 78-251 million NZD per year, for economic reasons pesticides have not given a satisfactory solution to this problem. Therefore, studies are currently being carried out on the introduction and establishment of natural enemies. Seven ecotypes of a parasitoid Microctonus hyperodae from South America (Brazil, Uruguay, Argentina and Chile) have been reared and released in three regions of New Zealand (northern ; central North Island, central South Island and southern South Island) from April to October 1991. First recoveries of M. hyperodae parasitized weevils were found from October 1991 to October 1992. In general, in all regions there has been a rapid establishment, especially in the warmer northern areas, and at all sites after initial establishment, parasitism has continued to build up, reaching 80 % in some areas.
Sources
Goldson, S.L.; McNeill, M.R., Proffitt, J.R.; Barker, G.M.; Addison, P.J.; Barratt, B.I.P.; Ferguson, C.M. (1993) Systematic mass rearing and release of Microctonus hyperodae (Hym: Braconidae, Euphorinae), a parasitoid of the argentine stem weevil Listronotus bonariensis (Col: Curculionidae) and records of its establishment in New Zealand.
Entomophaga, 38 (4), 527-536.