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
Citrus
October 9, 2017
(We Won’t Back Down … ) Stand Your Ground for Agriculture
You don’t have to be a super hero, rock star, or award-winning scientist to aid farming. You can help by supporting professionalism in fields. Read More
Greenhouse structure damage at SWFREC in Immokalee
Citrus
October 6, 2017
Complications Persist as Florida Growers Pick up After Irma
Ground zero perspective reveals how citrus and vegetable producers are facing different, daunting challenges in wake of destructive storm. Read More
pressure rinsing empty pesticide container
CEU Series
October 1, 2017
CEU Series: Mix and Load Pesticides Safely
Caution used during preparation stages are worth your time and effort. Read More
Crop Protection
September 27, 2017
AMVAC Expands Non-Crop Business by Acquiring OHP
Transaction to facilitate market access in the greenhouse and nursery markets. Read More
Sweet potato weevil
Insect Control
September 25, 2017
Prevent Sweet Potato Weevil From Giving You the Slip
Learn how to identify, the survival and spread, as well as management methods for this insect pest. Read More
Whiteflies on a leaf
Insect Control
September 20, 2017
Whitefly Troubles Go From Bad to Worse in Florida
Growers should have a plan for managing the pest from beginning to end of season. Read More
Bacterial wilt symptoms on blueberry leaves
Berries
September 20, 2017
Getting to the Bottom of Bacterial Wilt in Blueberries
Prolific plant pathogen now presenting a new challenge for Florida producers and researchers. Read More
Fruits
September 19, 2017
EPA Mulls Restricting Dicamba Use
Proposal is a part of agency’s focus on reducing herbicide injury in vulnerable crops. Read More
Laurel wilt-damaged avocado tree leaves
Disease Control
September 15, 2017
Scientist Uncovers Chilling Side of Deadly Avocado Disease
Lab tests indicate laurel wilt pathogen grows faster in the fall and winter. Read More
Biocontrols Conference
September 13, 2017
Get Better Results From Your Biopesticide Program
Softer crop protection programs are becoming a must in specialty crop production. Growers who aren’t learning more about their options Read More
Torn field plastic and drip tubing thanks to Irma
Citrus
September 13, 2017
Florida Farmers Digging out From Impacts of Irma
Damage reports flood in from the field following monster storm, and it's not pretty. Read More
Biocontrols Conference
September 11, 2017
The Grower’s Take: Citrus, HLB, and Biological Control
Uncle Matt’s Organic orange juice brand has enjoyed steady growth since its 2002 inception. The brand’s success is due to Read More
Insect Control
September 6, 2017
Vegetable Pest Populations Can Soar in High Tunnels, Study Shows
High tunnels alone are not enough to control pest populations, the study shows. To control pest levels, growers need to take other steps that allow ventilation while screening crops, and supporting natural predators. Read More
Biocontrols Conference
September 1, 2017
Dispelling the Rumors: Using Biologicals and Biochemicals in IPM Programs
Whether you’re a grower, packer, processor, or retailer, you have experienced the dramatic shift in consumer preference for sustainable practices Read More
Biocontrols Conference
September 1, 2017
Silicon: a Biocontrol Agent that Boosts Plant Immunity
Quality and profitability are two important factors that drive our agricultural markets. We have fine-tuned our cultivation processes over centuries Read More
The Latest
Crop Protection
October 17, 2017
EPA Takes Steps to Reduce Risk of Drift-…
With reports of dicamba injuries in tomatoes, peaches, grapes, and other crops, the agency works to reduce the impact of spray drift on vulnerable crops. Read More
Crop Protection
October 9, 2017
Field Scouting Guide: Black Rot of Brass…
Follow these tips for spotting and treating Xanthomonas campestris. Read More
Citrus
October 9, 2017
(We Won’t Back Down … ) Stan…
You don’t have to be a super hero, rock star, or award-winning scientist to aid farming. You can help by supporting professionalism in fields. Read More
Citrus
October 6, 2017
Complications Persist as Florida Growers…
Ground zero perspective reveals how citrus and vegetable producers are facing different, daunting challenges in wake of destructive storm. Read More
Crop Protection
September 27, 2017
AMVAC Expands Non-Crop Business by Acqui…
Transaction to facilitate market access in the greenhouse and nursery markets. Read More
Biocontrols Conference
September 13, 2017
Get Better Results From Your Biopesticid…
Softer crop protection programs are becoming a must in specialty crop production. Growers who aren’t learning more about their options Read More
Citrus
September 13, 2017
Florida Farmers Digging out From Impacts…
Damage reports flood in from the field following monster storm, and it's not pretty. Read More
Biocontrols Conference
September 11, 2017
The Grower’s Take: Citrus, HLB, and Biol…
Uncle Matt’s Organic orange juice brand has enjoyed steady growth since its 2002 inception. The brand’s success is due to Read More
Biocontrols Conference
September 1, 2017
Dispelling the Rumors: Using Biologicals…
Whether you’re a grower, packer, processor, or retailer, you have experienced the dramatic shift in consumer preference for sustainable practices Read More
Biocontrols Conference
September 1, 2017
Silicon: a Biocontrol Agent that Boosts …
Quality and profitability are two important factors that drive our agricultural markets. We have fine-tuned our cultivation processes over centuries Read More
Citrus
August 25, 2017
California EPA Seeking to Review Chlorpy…
Department of Pesticide Regulation, Office of Environmental Health pursuing health protections. Read More
Crop Protection
August 23, 2017
New Biological Fungicide Approved for Fr…
Howler fungicide, developed by AgBiome, receives EPA registration for high-value, specialty crops. Read More
Crop Protection
August 11, 2017
Do Fungicide- and Insecticide-Treated Se…
The University of New Hampshire has received half a million dollars to investigate if seed treatments inadvertently protect weed seeds from its usual predators. Read More
Citrus
August 11, 2017
Field Scouting Guide: Common Lambsquarte…
Take a look at these tips for identifying and treating this pervasive weed. Read More
Crop Protection
August 9, 2017
Why Some of the Most Dangerous Potato Di…
If you understand the role oxygen, and its lack, plays in potato diseases, you'll be better equipped to battle them. Read More
Crop Protection
August 3, 2017
Can Avocados Be Saved from Deadly Laurel…
Scientists from Florida and California are on the case and collaborating. Read More
Crop Protection
August 2, 2017
Report: 90% of NY Beehives Had Varroa Mi…
Cornell University's NYS Beekeeper Tech Team recent report also shows most hives are infected with Deformed Wing Virus (DWV), a disease linked to the mites. Read More
Biocontrols Conference
July 31, 2017
11 New Biocontrol Products You Need to K…
One of the highlights of the Biocontrols Conference & Expo Series is getting an early look at some of the Read More