Wirestem is caused by the fungus Rhizoctonia solani. Wirestem is associated with warm soil temperatures, excess soil moisture, and delayed seedling emergence. The disease develops when the fungus invades the cortical tissue and girdles young stems. Plants remain alive and continue to grow slowly, but give rise to spindly plants. R. solani can survive in soil as sclerotia, pathogenically on alternate hosts and weeds, and saprophytically on crop residues.
Wirestem symptoms appear as reddish brown to black, sunken lesions that form on cortical tissue and stems. Large lesions may girdle the stem and kill the plant, or produce a spindly, stunted, and yellow plant.
No biological control strategies have been developed for wirestem.
Encourage rapid seed germination and vigorous growth of seedling by planting high quality seed in warm, well-prepared seedbeds. Provide adequate but not excessive fertilization to promote vigorous growth of seedlings. Avoid planting into cold soils, excessive irrigation, poor drainage, and compaction. Ensure crop residues from the previous crop are thoroughly decomposed before planting. Crop rotation with non-hosts (i.e., small grains) may provide some reduction in wirestem.
Fungicides are most effective when used in combination with cultural control strategies.
Product List for Wirestem:
Pesticide |
Rate per 100 lb seed |
Application Frequency (days) |
Remarks |
PCNB |
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Terraclor 15G |
125 lb |
Planting time drench |
Broadcast or apply in band or seed |
|
Terraclor 75%WP |
15-20 lb |
Planting time drench |
Broadcast or apply in band or seed |
|
Terraclor Flowable |
1.9-3.8 gal |
Planting time drench |
Broadcast or apply in band or seed |
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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: Cole Crops, Disease, Wirestem
Date: 04/01/2007