Biosecurity Alert - Megoura crassicauda

06/10/2017

New Aphid incursion - Megoura crassicauda

Megoura crassicauda – “Vetch” or “bean” aphid

  • Crop Host range: only Vicia (e.g. vetches, faba beans, and broad beans).
  • Known areas affected – near Tamworth, Breeza (Liverpool plains) and Sydney – all sites have been small infestations in area but with large numbers of aphids. Further surveillance is being undertaken by New South Wales DPI in the growing areas of northern New South Wales
  • Natural predators: Megoura crassicauda may be to toxic to natural aphid predators such as ladybirds.The effect of other natural predators is unknown.
  • Management – There are no current registered insecticides for this pest. Dimethoate is registered to control aphids in faba beans. Paraffinic oil is registered for use on faba beans and vetches to control green peach aphid but only provides suppression. Initial work conducted by New South Wales DPI using pirimicarb was efficacious. Permits are being applied for pirimicarb, chlorpyrifos and lambda cyhalothrin.
  • Impact on crops: Likely to cause yield loss where there are high populations. Megoura crassicauda is reported to have a narrow host range consisting mainly of Vicia species. In Australia, it has the potential to become a problem for faba bean and (very likely) vetches. Observations in New South Wales have shown a very large reproductive capacity. The discrete observations within a crop indicated that only a few aphids landed, but that these were able to build up to a large population in a short time.

Image Source: New South Wales DPI

Blackman (1967) reported that M. viciae was toxic to certain ladybird species. In the observations in New South Wales only a few ladybird beetles were seen in severely Megoura crassicauda infested plants.

References

Hales et al. 2017. First detection of Megoura crassicauda mordvilko, (hemiptera: aphididae) in Australia and a review of its biology GEN. APP. ENT. VOL 45, 2017

Vetch aphid, Megoura crassicauda (Hemiptera: Aphididae), parasitism does not reduce the bean production of narrow-leaved vetch, Vicia sativa subsp. nigra (Fabaceae) Ecological Research

Cold hardiness of three aphid species, Acyrthosiphon pisumMegoura crassicauda and Aulacorthum solani (Hemiptera: Aphididae) Applied Entomology and Zoology Vol 37 2002

Morphological differences between wing morphs of two Macrosiphini aphid species Acyrthosiphon pisum and Megoura crassicauda (Hemiptera, Aphididae) Sociobiology 50(3) 881-893 2007

A hemiterpene glucoside as a probing deterrent of the bean aphid, Megoura crassicauda, from a non-host vetch, Vicia hirsuta. Phytochemistry 2006 Mar; 67(6):584-8. Epub 2006 Jan 24

Feeding responses of an oligophagous bean aphid, Megoura crassicauda, to primary and secondary substances in Vicia angustifolia.  Entomologia Experimentalis et Applicata Volume 121, Issue 1 October 2006

Should aphids attract or repel ants? Effect of rival aphids and extrafloral nectaries on ant–aphid interactions Population Ecology September 2000, Volume 42, Issue 2, pp 171–178