In this Issue:
VEGETABLE NEWS
STRAWBERRY NEWS
Strawberry Sampling Data from MDA
Strawberry IPM Update plus Fungal Diseases and Inoculum
APPLE NEWS
July 8, 2005 Minnesota Apple Growers Association (MAGA) Summer Tour
Weekly Trap Counts: June 13 - June 23, 2005
| Vol 2 No.8 | June 27, 2005 |
Strawberry IPM Update plus Fungal Diseases and Inoculum
Thaddeus McCamant, Specialty Crops Management Specialist, Northland Community & Technical College
Strawberry growers in the southern third of the state began picking this week. Few insect pests bother strawberries during harvest, but slugs have been showing up in many fields after our unusually wet weather. Slugs make small holes, usually at the bottom of the fruit. The danger of strawberry fruit diseases remains high.
During strawberry bloom, many farms had three or more gray mold infection periods, but many people were unable to spray fungicides on their plants on time. Some of the fields that were not sprayed will have little or no gray mold. Wet weather by itself cannot cause a disease. The wet weather must be combined with the presence of fungal pathogens. Some strawberry fields have little or no inoculum of certain diseases.
Inoculum refers to the part of the fungi that lands on and infects your plants. Most fungal inoculum are microscopic spores. Farmers can't monitor for fungal inoculum like they monitor for insect pests. By the time you see the fuzzy coverings on your berries, the spores have already spread.
The amount of gray mold inoculum in your fields increases as the fields age. Young fields on new ground may not have enough spores to cause an outbreak, but a field that has been in production more than three years will have gray mold. Anthracnose is found in about half of the fields in Minnesota . Unfortunately, the only sure way to find out if you have anthracnose in your soil is to see if your fruit develops brown spots during hot, wet weather near picking time. Leather rot is found in nearly all soils. If you have a soil that does not drain during heavy rain, assume that you have leather rot.
Many common production practices reduce the inoculum in your fields enough to reduce fruit diseases. Mowing your fields at renovation reduces gray mold and anthracnose inoculum. Frequently rotating fields also reduces inoculum. Removing diseased fruit from the fields during picking has not been shown to reduce inoculum.
| PLEASE NOTE: There will be NO newsletter published for July 4. We will resume publication for July 11 unless there is a MN State Government shutdown. If this occurs, then a web version of the newsletter will be available on the U of MN VegEdge site in htm format at: www.vegedge.umn.edu/MNFruit&VegNews/mnindex.htm and will contain only vegetable related information. |
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 Jeanne Ciborowski, 651-297-3217, jeanne.ciborowski@state.mn.us , MDA, 90 W. Plato Blvd., St. Paul, MN 55107-2094. 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: www.mda.state.mn.us/biocon/fruitreports/
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. ©1999-2005 Minnesota Extension Service, University of Minnesota. All rights reserved. Contact copyright@extension.umn.edu for information on reproduction or use of this material.