The risk to Solanum spp. in New Zealand from Gargaphia decoris (Hem.: Tingidae), a potential biocontrol agent against woolly nightshade, S. mauritianum

摘要

Woolly nightshade, Solanum mauritianum (Solanaceae) is a serious environmental and forestry weed in New Zealand. The leaf-feeding lace bug. Gargaphia decoris (Tingidae), was released in South Africa in 1999 after rigorous host specificity testing revealed that natives and crops in the genus Solanum were unlikely to be attacked. All three New Zealand native Solanum spp. were similarly tested in South Africa. Neither Solanum laciniatum, Solanum aviculare (poroporo) nor Solanum americanum (small-flowered nightshade) supported feeding by nymphs or adults of G. decoris in no-choice tests. During multichoice tests, 97 percent of adults selected S. mauritianum, while 2 percent selected eggplant cv. Black Beauty (S. melongena). Oviposition occurred only onS. mauritianum. The risks of non-target attack are therefore low enough to warrant further evaluation of G. decoris as a biocontrol agent in New Zealand.