Avoid The Scorn Of Seedcorn Maggots

Photo by Whitney Cranshaw
Photo by Whitney Cranshaw, Colorado State University

Pest Specs

The seedcorn maggot (Delia platura Meigen) or bean seed fly is a small fly closely related to the cabbage maggot and the onion maggot. It is a sporadic pest on germinating seeds of corn and many other agronomic and horticultural plants.

Identification

The pest is cosmopolitan occurring on all continents except Antarctica. Seedcorn maggots damage newly planted seeds by feeding on seed contents, often leaving empty seed shells and preventing germination. Seedlings that germinate despite the damage are spindly, with few leaves, and die before maturation. Usually a small percentage of the seedlings get infested by this insect. But in severe cases, as much 30% to 60% plant loss may occur in the field.
The adult seed corn maggot is a brownish-gray fly with three stripes on its back. They resemble a small house fly but are about half the size and hold their wings crossed over the abdomen at rest.
The legless larvae maggots are dirty white with a yellow tint, legless, cylindrical, and tapered in shape. Fully grown maggots are about ¼-inch long and have a pointed head with two black mouth hooks. The abdomen is blunt with two brown to black spiracles at the posterior end.
This pest is associated with organic matter such as manure and plant residues. Seedcorn maggot activity increases during years when conditions are cool and damp and seeds germinate slowly. They may be more common in reduced-tillage systems as the decaying organic matter from crop residues is an ideal ovipositional site for the insect.

Survival And Spread

The flies mate within a few days after emerging, and each female lays an average 270 eggs in soil high in decaying organic matter and/or on seeds or plantlets in moist soil. Females lay eggs near food sources and tend to deposit more eggs near the base of newly emerged seedlings. The eggs are white, deposited in loose groups among organic debris and around plant stems near the soil surface.

The larval period lasts nearly 21 days and the maggots develop over a wide temperature range. They complete their entire development within the soil by burrowing into and feeding on seeds or emerging cotyledons. Larvae also can survive as soil saprophytes.
The insect can pass through up to five generations per year in the South, and adults are common in the fall, early winter, and spring seasons. However, few are seen in mid-summer as they appear to be intolerant of high temperatures. Since much of the life cycle is spent protected underground, the seedcorn maggot does not appear to have many natural enemies.

Management Methods

Preventative measures include late planting, shallow planting, higher seeding rates, well-prepared seedbed, and turning undercover crops early, which renders fields less attractive to egg laying.
Insecticidal seed treatment is the cheapest and most effective treatment for the control of seedcorn maggots. Granular insecticides also can be used for control.
Consult UF/IFAS recommendations for currently labeled insecticides for seedcorn maggot control.

Topics: , ,

Leave a Reply

Crop Protection Stories
Crop ProtectionSustainable Options For Controlling Brown Marmorated Stink Bug In Vegetables
August 31, 2015
A researcher from Rutgers University offers pointers to help you control this pest of fruits and vegetables. Read More
money
CitrusMonsanto Drops Current Bid For Syngenta Acquisition
August 27, 2015
Even with a revised proposal that sweetened the pot to $46.2 billion, financial expectations still fall flat. Read More
Crop ProtectionOnline Help In Determining ID Of Small Parasitic Wasps
August 25, 2015
A web-based document helps users navigate to the correct genus or species of a wasp. Read More
Disease ControlBioSafe Systems’ ZeroTol 2.0 Now OMRI Certified
August 25, 2015
Broad spectrum bactericide/fungicide is now cleared for use in organic production. Read More
Crop ProtectionReinforcing Agriculture Research Of Utmost Importance [Opinion]
August 21, 2015
We are still a ways out from finding the best replacement combinations for methyl bromide, but we’ll get there. Read More
CitrusSouth Florida Farmers Feted For Water Quality Standards
August 20, 2015
Marking 20 straight years of success, producers help Everglades Agricultural Area exceed phosphorus reduction goals. Read More
old world bollworm climbing on vegetation
CitrusOld World Bollworm A Potential New Pain For Florida Farmers
August 20, 2015
Growers in the Sunshine State on high alert as serious pest is detected for the first time in the U.S. outside of port interceptions. Read More
The Latest
Crop ProtectionNimitz Receives Section 24(c) Label In Florida
September 4, 2015
The nematicide can be used in several Florida counties on direct-seeded crops. Read More
Apples & PearsSyngenta Receives EPA Registration For Solatenol  Fungi…
September 1, 2015
The fungicide is available in four product offerings, pending state registrations. Read More
Crop ProtectionSustainable Options For Controlling Brown Marmorated St…
August 31, 2015
A researcher from Rutgers University offers pointers to help you control this pest of fruits and vegetables. Read More
money
CitrusMonsanto Drops Current Bid For Syngenta Acquisition
August 27, 2015
Even with a revised proposal that sweetened the pot to $46.2 billion, financial expectations still fall flat. Read More
Crop ProtectionOnline Help In Determining ID Of Small Parasitic Wasps
August 25, 2015
A web-based document helps users navigate to the correct genus or species of a wasp. Read More
Crop ProtectionReinforcing Agriculture Research Of Utmost Importance […
August 21, 2015
We are still a ways out from finding the best replacement combinations for methyl bromide, but we’ll get there. Read More
Keith Jones
CitrusBiopesticide Industry Alliance Names Keith Jones As New…
August 10, 2015
The Biopesticide Industry Alliance (BPIA) announced its selection of Keith Jones as its new executive director. Mr. Jones is an Read More
Crop ProtectionLettuce Disease Gives E. Coli A Boost
July 31, 2015
E. coli prefer cut, injured, and young lettuce leaves. Read More
Crop ProtectionResources For Knowing Your Soil
July 30, 2015
Getting to know your soil and learning other environmental and natural resources data can be downloaded and is available for use with many computer software platforms for general resource analysis and farm management. Read More
Crop ProtectionNew Fungicide Targets Key Diseases
July 30, 2015
This disease control tool hits two different parts of the fungal life cycle. Read More
Bill Stoneman
Crop ProtectionFormer BPIA Head Relishes Challenge Of New Consulting R…
July 28, 2015
JET Harvest Solutions taps Bill Stoneman for his bounty of biocontrol experience. Read More
Crop ProtectionRegional Integrated Pest Management Grants Reduced Pest…
July 22, 2015
The program created tools and training information designed for Western growers. Read More
Crop ProtectionClue Into Chemigation Best Practices
July 15, 2015
Monitoring performance and quick repairs are critical to successful applications. Read More
Crop ProtectionNew Egg Cage System Could Increase Ladybug’s Bioc…
July 13, 2015
A specialized insect cage system developed by USDA scientists could improve the prospects of mass rearing the pink spotted lady Read More
Crop ProtectionIR-4 Call For Nominations For “SOAR” Award
July 10, 2015
The IR-4 Project, a resource that supplies pest management tools for specialty crop growers by developing research data to support Read More
Crop ProtectionEarly Blight And Septoria Leaf Spot Rampant On Pennsylv…
July 8, 2015
According to a news release from Penn State University, early blight and Septoria leaf spot are present in Pennsylvania tomato Read More
Crop ProtectionDowny Mildew Reported In Ohio Cucumber Fields
July 8, 2015
According to a disease update from Ohio State University Extension, downy mildew was reported in cucumbers on farms in West Read More
Crop ProtectionZeal SC Miticide Now Registered With Liquid Formulation
June 26, 2015
Valent U.S.A. Corporation announced that Zeal SC Miticide has been registered by the EPA with a new liquid formulation that Read More