INTRODUCTION

ISSUE 1  May 3, 2001

Welcome to another year of the North Dakota Crop and Pest Report. We will be with you for the next sixteen issues. Good Luck this season. If you have comments about agricultural production concerns you would like to see discussed, feel free to contact us. Check the back page for telephone numbers, addresses, or e-mail.

The staff

AGDAKOTA@NDSUEXT.NODAK.EDU

The mailing list, AGDAKOTA, has been established for six years, now. AGDAKOTA has been set up to promote the exchange of information between ag professionals about current events in North Dakota agriculture. The forum is suited for asking questions of your colleagues about production and pest issues. It is also a place to provide updates on what is happening currently in the fields around the state and region. The editor of the list is Phillip Glogoza, NDSU Extension Entomologist. His e-mail address is:

pglogoza@ndsuext.nodak.edu

If you would like to subscribe, send a mail message to Majordomo@ndsuext.nodak.edu with the following message:

subscribe agdakota <your e-mail address>

This mailing list promotes networking on ag production issues among ag professionals in the state of North Dakota. The mailing list serves as a common e-mail address. When a message is sent to the server, it is delivered to all the subscribers. If private correspondence is desired, then messages can be sent to a persons personal e-mail address. To send a message to AGDAKOTA, the e-mail address is:

ProCrop is a crop production data base containing crop production information produced by NDSU crop production specialists. It has been updated and available to you at the site address listed below.

http://www.ag.ndsu.nodak.edu/aginfo/procrop/procrop.htm

It is easy to use; click on the crop area you wish to review and use the key words to select your material. There are over 1200 files and links to other sites. ProCrop is designed to provide fast reference information. If you have suggestions for additional material or improvements or need assistance in becoming familiar with ProCrop, please contact me. I hope you find ProCrop to be a useful and handy reference for your crop production questions this summer.

Terry Gregoire
Area Extension Specialist/Crop Production
Devils Lake

SEED TREATMENTS FOR DISEASES & INSECTS

Seed treatments promote seedling health and aid establishment by protecting young plants from early diseases and insect problems. The following are some comments about the use of seed treatments that should be considered.

Considerable root rot was observed in spring wheat and durum last year, with grain heads turning prematurely white and often empty of grain. Root rot was severe in some fields, especially fields that had been wet for an extended period where good root systems did not develop prior to the warm, drier period of late July. Methods for reducing the risk of root rot include crop rotation into broadleaf crop ground, more tolerant varieties, and seed treatment.

Although a considerable amount of wheat and barley has been planted by the time of this report, a lot of acres are still left to plant, as well, and seed treatment should be considered for acres at risk to root rot. The following are examples of seed treatment products that are registered for wheat and have activity against root rot. The most frequent root rot problem in ND is common root rot, but take-all root rot was observed in the NE last year, too.

Wheat Seed Treatments and Root Rot Control

* Also labeled for barley

Black point symptoms have been observed in quite a few wheat seed lots from this past year. Black point symptoms are characterized by a dark brown to black discoloration of the embryo end of the grain kernel. Black point symptoms are caused by one or more fungi, including Bipolaris sorokiniana (= Helminthosporium sativum = cause of common root rot), Alternaria species, and Pyrenophora tritici-repentis (cause of tan spot). Upon seed germination, these fungi can cause seedling blight or they may invade the roots and initiate root rot.

Seed treatments are definitely warranted in these seed lots and the seedling blight phase can be controlled with many fungicide seed treatments. The root rot phase can be controlled with seed treatment products listed in the above table provided in the root rot seed treatment section.

Seed or planter box treatments are used on a wide variety of North Dakota crops for protection from seedcorn maggot, wireworms, and/or seedcorn beetle. The following tables highlight common treatments and labeled crops. The insecticide component of these treatments is either lindane, diazinon, chlorpyrifos, permethrin , or tefluthrin and should provide early protection to seeds from feeding by the above soil insects.

Planting into cool, wet soils put young seedlings at greater risk to injury from insects. Keep weather conditions in mind when making final planting decisions.

Some Common ND Seed Treatments with Insecticide
(labeled crops indicated by "x")

Do not confuse seed inoculation with chemical seed treatment. Most seed disinfectants, including fungicides, are toxic to Rhizobia bacteria. Do not apply inoculum to seeds that are treated with a bactericide, such as streptomycin, unless you use a resistant strain of the Rhizobia. Although some Rhizobia species are slightly tolerant to certain chemical compounds, inoculating chemically treated legume seed requires special precautions. Check with the inoculum manufacturer regarding compatibility when considering combining products.

Here are some general guidelines when using seed treatments and inoculants:

• Insecticides are more toxic than fungicides, which are more toxic than herbicides.
• In-furrow inoculant applications are preferred when seed treatments have been used.
• If a seed treatment and inoculant are combined on the seed, minimize exposure time, less than 4 hours is best. Some Rhizobia may be killed immediately, check compatibility charts prior to use. The 2001 Fungicide Guide also has information about fungicide seed treatment effect on inoculants.
• If liquid pesticides are used, apply first and allow to dry before inoculant is applied
• Powder-based inoculants protect Rhizobia better than liquid based inoculants
• When using pre-treated seed, check with the inoculant formulator for comments on compatibility .

Seed treatment information compiled by
Marcia McMullen, Plant Pathologist and Phillip Glogoza, Entomologist