By Dr. Debra Moreau and Jessica MacDonald, AAFC
debra.moreau@agr.gc.ca or 902-402-5397 July 21
As part of the Canadian Grape and Wine Cluster, we are
researching the distribution and impact of emergent and invasive insect pest
species in the context of viticultural expansion in Nova Scotia.
I am particularly interested in determining the presence of Grape Berry Moth and the spread in distribution of Japanese beetle. If you notice damage (descriptions of what to look for are provided below) and/or see either of these insects, please feel free to contact me. I will make every effort to visit your vineyard to collect any samples that you may have set aside. Please feel free to send me your photos of vineyard pests and insects of interest, just stick your thumb or some other known object in the frame so that I have a sense of scale.
Japanese Beetle (Popillia japonica)
What to look for:
·
Adult beetles average 15 mm in
length
·
Metallic green head and thorax
with coppery brown back
· There are small white tufts along the sides and at the back
·
The antennae are clubbed at the
end
· Where you find one, there are often more (they tend to cluster)
· When disturbed, they will drop to the ground.
Damage
·
Adults will feed on the upper
surfaces of leaves in the top portion of the canopy
·
Extent of damage will vary but can
be severe in some vines and varieties
·
In NS, we typically start seeing
the adults feeding by mid-late July
Grape Berry
Moth (Paralobesia viteana Clemens)
What to look
for:
•
Infestations can vary greatly from year to year and are often very uneven
in a vineyard (if established, then scout in vineyard areas closet to woody
borders).
• Look for maturing larvae (caterpillars) in developing clusters. Mature larvae can reach 10mm in length larvae are a dark purple colour
Damage:
•
Webbing may be seen in cluster
•
Often a reddish spot surrounds the point of larval entry. The
discoloration can extend over half of the surface of an otherwise green berry.
•
Larvae feed inside the fruit
•
Risk when fruit is 6-8mm dia.
Photo credits: NS Growers for top image of ‘suspected’
GBM larvae, webbing and Jacques Lasnier (Co-Lab R&D, Granby, QC) for feeding damage shown in
bottom image.
References:
Lasnier, J., McFadden-Smith, W., Moreau, D., Bouchard,
P., and Vincent, C. Guide to the key
arthropods of vineyards of Eastern Canada. Agriculture and Agri-Food Canada,
2019. http://publications.gc.ca/pub?id=9.868732&sl=0
http://www.omafra.gov.on.ca/IPM/english/grapes/insects/gbm.html#advanced
http://www.omafra.gov.on.ca/IPM/english/grapes/insects/japanese-beetles.html#advanced
Saunders, M., Isaacs, R., and Loeb, G. 2013. Focus on females provides new insights for grape berry moth management. Research Focus 2013-2: Cornell Viticulture and Enology. https://ecommons.cornell.edu/bitstream/handle/1813/103671/Research-Focus-2013-2-gbm-management.pdf?sequence=1&isAllowed=y