Several fungi can cause kernel smut, including Ustilago crameri and Sporisorium neglectum. These fungi survive in soil as dormant spores (chlamydospores). These chlamydospores germinate and produce a basidium from which air-borne spores (lateral branches or sporidia) are formed. Little is known about the conditions that favor the pathogens and disease.
The kernal smut pathogens cause floral tissues of diseased plants to convert into fungal fruiting bodies that appear dry and olive green (U. crameri) or purple-brown (S. neglectum). Before heading, microscopic examination is necessary to observe the fungus.
No biological control strategies have been developed for kernel smut.
Practice a three-year or longer rotation to non-hosts such as sunflower, corn, or small grains.
Broad spectrum seed treatments should be used routinely.
Product List for Kernel Smut:
Pesticide |
Rate per 100 lb seed |
Application Frequency (days) |
Remarks |
|
Captan—various formulations available |
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Captan 75 |
6-9 oz |
Seed treatment |
Broad spectrum, but weak against Pythium |
|
Fludioxonil |
|
|
|
|
Maxim 4FS |
0.034-0.068 fl oz |
Seed treatment |
Suppression of Fusarium and Rhizoctonia spp. |
|
Thiram |
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|
42-S Thiram |
8 fl oz |
Seed treatment |
Broad spectrum |
|
Thiram 50WP |
8 oz |
Seed treatment |
Broad spectrum |
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The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana. Criticism of products or equipment not listed is neither implied nor intended. Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein. Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies. State rules and regulations and special pesticide use allowances may vary from state to state: contact your State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality. |
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Categories: Millet, Disease, Kernel Smut
Date: 03/22/2005