Dry Edible Beans: Seedcorn Maggot (Delia platura)

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Pub 812: Field Crop Protection Guide > Chapter 5: Dry Edible Beans > Seedcorn Maggot

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Field Crop Protection Guide 2011-2012, Order 2011-2012 publication

Table of Contents

1. Description
2. Integrated Pest Management Options
   • Seed Treatment
     • thiamethoxam – Cruiser 5FS
     • thiamethoxam + metalaxyl-M + fludioxonil - Cruiser Maxx Beans
     • diazinon + captan + thiophanate-methyl – DCT
3. Related links...

Description

The seedcorn maggot is a small, yellowish-white, headless, legless larva. The body tapers to the front with two small mouth hooks protracting. The maggots burrow into germinating seeds and the below-ground parts of emerging seedlings, producing weak seedlings. The adults resemble a small housefly that is slender, light grey and approximately 5 mm in length.

Image 1. Seedcorn maggots are small, headless, legless larvae that burrow into germinating seeds and weaken the seedling.

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Integrated Pest Management Options

Seed Treatment

Seedcorn maggot problems in dry beans are rare in Ontario. Risk factors include cool, wet springs when germination is delayed. In fields at high risk, including early-planted fields where large amounts of manure, green manure or residue have recently been incorporated, use Cruiser seed treatment.

Active ingredient	thiamethoxam
Trade name	Cruiser 5 FS
Rate (product)	50-83 mL per 100 kg seed
Comments	For use in commercial seed treatment facilities only. Use higher rate when expecting high insect populations. May be mixed with Apron Maxx RTA for control of seed and soil-borne pathogens. Do not graze or feed livestock on treated areas for 45 days after planting.

 

Active ingredient	thiamethoxam + metalaxyl-M + fludioxonil
Trade name	Cruiser Maxx Beans
Rate (product)	195 mL per 100 kg seed
Comments	For use in commercial seed treatment facilities only. Compatible with Rhizobium-based inoculants. Check with inoculant manufacturers for details prior to use. For anthracnose control, tank-mix with 10 mL of Dynasty 100FS per 100 kg seed. Do not graze of feed livestock on treated areas for 45 days after planting.

 

Active ingredient	diazinon + captan + thiophanate-methyl
Trade name	DCT
Rate (product)	1 L of slurry
Comments	Available in a 400-g container that will treat 77 kg of dry bean seed. Use full rate and ensure good coverage by applying as a slurry. To make slurry, use 520 g seed treatment/L of water.

 

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Related links...

• Agronomy Guide for Field Crops - Publication 811
  • Dry Edible Beans: Seedcorn Maggot
• Insects
• Dry Edible Beans