Cucurbits XXX-5

Note On a Secondary Pest - Leafminers

Whitney S. Cranshaw & Michael J. Brewer

Leafminer

Note: Cucurbits may be easily injured by formulations of some insecticides. It is often a good precaution to not apply insecticides when foliage is wet. Be sure to check label before using to make sure insecticide will not cause plant injury and/or perform a small-scale test application to verify safety.

Serpentine leafminer larvae tunnel through the foliage of plants and may occasionally be problematic on melons. The tunnels are thin and meander within a leaf. Problems are most severe in insecticide treated fields because treatments can kill natural enemies of the leafminer. Vigorously growing vines will be little affected by leafminer injury. No injurious pathogens are vectored by this insect. Use of the following insecticides may be warranted should mining be extensive. Please note that extensive mining may be a result of excessive insecticide use for other pests. In addition to controlling excessive leafminer populations, a review of the entire pest control program is likely warranted.

Note: The following products are registered for melons and may or may not be registered for other cucurbit crops. Check product labeling for usage restrictions.

Product list for Leafminers:
Insecticide	Product per acre	Preharvest Interval, Remarks
Cygon 400, Dimethoate 400	1.0 pt	(3 days) Four day reentry interval. Systematic insecticide.
Dimethoate 267	1.5 pt	Organophosphate insecticide (dimethoate). Do not store below 45 degrees.
^RRestricted use pesticide. ^1Labeled for chemigation ^2Generic active ingredient, several formulations.
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.

Categories: Insects, Cucurbits, Cucumber, Melons, Squash, Pumpkins, Leafminers

Date: 05/05/2002