Several species of nematodes can cause economic damage to spinach in the High Plains production region, including root lesion, cyst, needle, sting, and root-knot nematodes. Other nematode species have not been studied extensively in the High Plains and are not known to cause economic damage to spinach in the High Plains. The life cycle of different nematode species vary, and may include feeding on the outside of roots or penetration and development within roots. Nematodes survive between susceptible crops by feeding on other crops and weeds, and, sometimes, as dormant cysts. Nematodes can be spread in and among fields by contaminated soil on machinery, windblown soil, irrigation water, and infested transplants.
Above ground symptoms of nematode injury appear as patches of stunted or dying plants. When roots are examined they appear pruned, but some nematodes (such as the cyst nematode) can cause a proliferation of lateral feeder roots. Other nematodes can cause round to spindle-shaped galls on roots (root knot), reddish-orange to brown lesions (lesion), swelling and distortion (needle), and necrotic lesions that girdle roots (sting). Infected plants may wilt when stressed by high temperature or moisture stress.
Incorporation of green manure crops such as sudangrass, sesame, rapeseed, white mustard, or perennial ryegrass the season before a spinach crop is planted can reduce some nematode populations.
Prevent the introduction of nematodes in clean fields by thoroughly cleaning equipment between fields. Plant transplants free from nematodes. Avoid the reuse of irrigation water. Provide adequate fertilizer and irrigation for crop development to reduce the impact of nematode feeding. Sprinkler irrigation tends to be more effective than furrow irrigation for supplying uniform water to nematode-damaged plants. Practice a three-year or longer crop rotation to non-hosts such as small grains. Control weeds that may serve as alternate hosts of nematodes. Promptly incorporate crop residues after harvest to limit nematode reproduction. Few if any spinach varieties are resistant or tolerant to nematodes.
Nematicides and soil fumigation effectively suppress many nematode species, but are most effective when combined with cultural practices that reduce nematode populations. Chemical controls are generally only cost effective when nematode injury is severe and widespread. Nematode injury often only occurs in localized areas in fields, and these areas can be effectively managed by spot-treatments with nematicides.
Product List for Nematodes:
Pesticide |
Product per acre |
Remarks |
|
|
|
Restricted use; Preplant application, aerate 7-14 days. |
|
Telone C-17 |
10-17 gal |
Restricted use; Preplant application, aerate 7-14 days. |
|
Vapam |
40-100 gal |
Restricted use; Preplant application, aerate 7 days. |
|
Vorlex |
7-15 gal |
Restricted use; Preplant application, aerate 14 days. |
|
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: Spinach, Diseases, Nematodes
Date: 04/01/2007