MN Fruit & Vegetable IPM News - Vol. 3, No. 1

Plant injury is caused by the adult female weevil. The female clipper girdles the bud, where she inserts an egg and clips the stem, causing the bud to hang down or fall to the ground. Injury is most common along edges of fields near woodlots.

Flower thrips

Fruit injury results when thrips feed on strawberry blossoms after fertilization has occurred. The stigmas and anthers turn brown and wither prematurely. As fruit develops, thrip feeding may cause fruit russeting around the cap, but this injury is seldom economic. Seedy berry symptoms include reduced fruit size, dull color, leatheriness, and seediness all over. Thrip injury is uncommon, but rare outbreaks can ruin an entire crop.

Tarnished plant bug (TPB)

Fruit injury can occur from adult and nymph feeding. Tarnished plant bug feeding on strawberries can produce cat-faced berries. The female tarnished plant bug inserts eggs into soft plant tissue and may cause damage by feeding upon the developing buds of the strawberry. Nymphs begin to emerge 7-10 days later and both adults and nymphs feed on the developing

achenes (seeds) during and after bloom, and on the receptacle of the developing fruit. Their feeding kills surrounding tissue and leads to small seedy strawberries that fail to mature (button berries).

More information about these strawberry pests is available in:

Field Guide for Identification of Pest Insects, Diseases, and Beneficial Organisms in Minnesota Strawberry Fields at www.mda.state.mn.us/ipm/strawberryfg and Integrated Pest Management Manual for Minnesota Strawberry Fields at www.mda.state.mn.us/ipm/berrymanual

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ACKNOWLEDGEMENTS

Co-Editors: Bill Hutchison ( hutch002@umn.edu), Department of Entomology, University of Minnesota, Jeanne Ciborowski, Minnesota Department of Agriculture, Ag. Resources Management and Development Division, and Suzanne Wold-Burkness ( woldx018@umn.edu), Department of Entomology, University of Minnesota

The Newsletter is published weekly from May through August, cooperatively, by the Minnesota Department of Agriculture (MDA) and the University of Minnesota (U of MN). Reports are posted on the U of MN and MDA web sites on Fridays. If you have suggestions and/or comments, please send your contributions by 4 p.m., Wednesday to Jean Ciborowski, 651-201-6217, jeanne.ciborowski@state.mn.us, MDA, 625 Robert St. North, St. Paul, MN 55155-2538. You can access the Newsletter at the U of MN web site in htm format at: www.vegedge.umn.edu/MNFruit&VegNews/mnindex.htm and at the MDA web site in pdf format at: http://www.mda.state.mn.us/ipm/ipmnews/

Partial funding for this publication is provided through partnership agreements with the Minnesota Fruit and Vegetable Growers Association (MFVGA) and the United States Department of Agriculture – Risk Management Agency (RMA). These institutions are equal opportunity providers.

DISCLAIMER

Reference to products in this publication is not intended to be an endorsement to the exclusion of others which may have similar uses. Any person using products listed in this publication assumes full responsibility for their use in accordance with current manufacturer directions.

The University, including the Minnesota Extension Service, is an equal opportunity educator and employer. ©1999-2006 Minnesota Extension Service, University of Minnesota. All rights reserved. Contact copyright@extension.umn.edu for information on reproduction or use of this material.