Which species of Tortricidae leafrollers are key insect pests in South Australian vineyards?

Light brown apple moth, Epiphyas postvittana (Lepidoptera: Tortricidae) is regarded as the key insect pest in Australian vineyards and it is also an important pest of apples and citrus. E. postvittana is indigenous to Australia and has a wide geographical distribution. Recent observations suggest that leafroller species other than E. postvittana may be causing damage in grapevine canopies. A study of tortricids was undertaken in Adelaide Hills and McLaren Vale vineyards, South Australia. A total of 407 specimens of Tortricidae were collected from grapevine canopies. Molecular techniques were used to identify species. The mean prevalence of E. postvittana per sample was 91.0% in 2014/15 and 96.2% in 2015/16. Larval Acropolitis rudisana, lucerne leafroller, Merophyas divulsana and cotton tipworm, Crocidosema plebejana were also found on the grapevine canopy at much lower densities for the first time. The presence of leafroller species A. rudisana, M. divulsana and C. plebejana on grapevines confirms these species of Tortricidae may also be present in South Australian vineyards. This study confirms that E. postvittana is the most common tortricid pest in Adelaide Hills and McLaren Vale vineyards and also illustrates the utility of molecular methods in determining with confidence the species identity of larval Tortricidae.