Black light trap catches of AGB per 3 to 4 nights in Sussex County, Virginia were 500 on June 7 and 487 on June 10, 2024. Producers have reported seeing adult AGB just by kicking over the top inch or so of soil in infested areas. I heard of 5 acres of cotton in Suffolk with very heavy AGB defoliation, but there are more reports where injury is not as severe. I look forward to learning when our AGB population will finally decline.
Barley yellow dwarf virus (BYDV) is a significant threat to small grains worldwide and is currently impacting winter wheat in Virginia. This virus is transmitted by cereal aphids. In addition to wheat, BYDV can also infect barley and other perennial grassy hosts, including forage crops such as tall fescue. Yield losses to BYDV often do not exceed 30-35%; however, excessive losses have also been reported in some regions.
Our ongoing survey in Virginia is indicating a widespread BYDV infection. Nearly all the samples tested in 2024 have been positive for BYDV. These samples were received from Augusta, Culpeper, Essex, Prince George, Shenandoah, Montgomery, Northumberland, and Nottoway counties.
Symptoms
BYDV symptoms include reddening or yellowing of leaves (starting from the tip and leaf edges), reduced root biomass, and decreased stem height, ultimately affecting yield and grain quality (Fig. 1). These symptoms also resemble those of other conditions; therefore, laboratory testing is needed to confirm BYDV infection.
Management
Once infected, there is no remedy for the affected plants. However, a combination of cultural and chemical approaches can help minimize the risk of BYDV spreading.
Managing weeds and volunteers can eliminate BYDV and aphid reservoirs. Late fall planting provides an opportunity for the young seedlings to evade infestation by aphids that are on the move from reservoirs. Seed treatment with systemic insecticides combined with late planting are expected further to minimize the risk of BYDV infection in the fall.
Infections that occur in the spring are not expected to result in significant losses since plants often outgrow BYDV infection.
Mapping BYDV distribution in Virginia
We are currently investigating the distribution of BYDV in Virginia and evaluating factors that can predict the risk of BYDV incidence. You can contribute to our ongoing research by sending plant samples for BYDV testing; samples will be tested free of charge. Your participation will help us better understand the prevalence and transmission dynamics of BYDV in Virginia, enabling us to develop targeted management strategies to mitigate the risk of BYDV incidence in agricultural landscapes.
Please fill out this form and include it with your plant samples.
This article is prepared by Shirin Parizad.
Captures of Asiatic garden beetle (AGB) in our black light trap climbed this past week, with 300 adults caught between May 31 and June 3, 2024. We do not know if we have reached peak emergence yet for this sporadic pest. Johnny Parker (Commonwealth Gin) reported three Virginia seedling cotton fields with AGB injury so far this season, with defoliated areas reaching 2 acres. Check for these insects under weeds such as pigweed, marestail, or volunteer soybean–focus especially on sandy soils. You may see round adult emergence holes in the ground. Or, a visit to the field at night (when adult AGB are active) may confirm the problem.
In a June 4, 2024 Pest Alert, Dr. Dominic Reisig and Dr. Guy Collins (North Carolina State University) provide AGB scouting and management information which is also applicable for Virginia cotton growers. Contact insecticides would need to be applied during peak emergence, and at night.
As most of you know, corn earworm is a devastating pest of many crops in Virginia.
This native moth pest can successfully overwinter as pupa in Virginia when winters are relatively mild. Virginia crops will also get the usual dispersal of moths coming up from the southern states after mid-July that will lay eggs on many crops that flower in late summer.
Last week Mr. Bill Tiver from Halifax County reported 10 moths per night in his corn earworm trap placed on his farm and larvae already infesting some of his earliest sweet corn. In addition, VCE agent Helene Doughty, in Cape Charles, VA on the Eastern Shore recorded high numbers in the corn earworm moth trap placed there. This is definitely some early warnings of a potentially bad corn earworm year. We most definitely had higher than usual insect overwintering success in Virginia this year.
In 2023 there were multiple, scattered reports of severe defoliation and/or death to cotton seedlings caused by Asiatic garden beetle (AGB) in Virginia and northeast North Carolina. Infested cotton areas varied in size, with some reaching 10 acres. AGB feed on roots (as grubs) and foliage (as adults) of many different host plants. The adults hide in the soil during the day and feed at night. AGB prefer sandy soil over heavier soil. When we visited the infested cotton fields, we often found AGB in the soil below weeds (e.g., marestail) and volunteer soybean plants.
This April the Tidewater Agricultural Research and Extension Center’s entomology program began sampling field “hotspots” from the 2023 season using soil samples, pitfall traps, and a black light trap. We found AGB grubs in soil samples from fields in Wakefield and Sussex County, VA, but did not find them in a northeast North Carolina field infested last year. AGB grubs can be differentiated from other white grubs by their “puffy cheeks.”
The black light trap is being operated in Sussex County, VA; it had a peak of 114 AGB adults (total per 3 nights) on May 9, 2024, followed by a sharp decline in captures. Other states have reported a single generation of AGB per season, but we plan to keep monitoring for several more weeks. We are still finding grubs and pupae in our soil samples. Pitfall traps placed in the field, designed to capture crawling adults (not flying due to cool temperatures), have not captured any AGB so far.
Cotton infestations and seedling injury from 2023 may have been due in part to cool May temperatures, keeping AGB adults on the ground, feeding in the cotton fields where they emerged; the cooler weather also limited cotton seedling growth.
We’ll provide further updates as we learn more. If you suspect an AGB problem in your seedling cotton, please feel free to reach out to me, or contact your county Extension Agent.
Acknowledgements: We are grateful for the financial support provided by Cotton Incorporated and the Virginia State Cotton Support Committee, and for the assistance provided by local cotton growers.
Greetings friends across Virginia. My graduate student, Hannah Swarm, is researching the ecology and management of wireworms in Virginia. Wireworms are the subterranean larval stage of click beetles and can be quite damaging to many crops including potato, sweetpotato, corn, grains, carrot, hemp, to name a few.
For one of her research objectives, we are hoping to document the different species of wireworms that are found in the different regions of the state (Coastal, Piedmont, mountains).
If you happen to have a decent field where we could come visit and dig around the outside perimeter and collect wireworms, we would greatly appreciate it. Please, email us: hannahswarm711@vt.edu and tkuhar@vt.edu. We are collecting during the months of April and May. Many thanks.
Yield reductions in small grains can result from cereal leaf beetle larvae feeding on leaf photosynthetic tissue. Infestations in Virginia are sporadic, but if you scout for them I wanted to share the following information. A temperature-based model indicates that Suffolk (Virginia) will reach the egg peak for this pest on March 22, 2024 (that’s the day when 182 degree days have accumulated). The model uses January 1 as a biofix; a lower development threshold of 8℃, and an upper development threshold of 25℃.
Eggs are yellow-orange, elliptical, about 1/32-inch long, and are often found along the midvein of the leaf.
The larval peak follows the egg peak by an average of 17.5 days, which is predicted to fall during the second week of April for Suffolk.
To scout for cereal leaf beetle, inspect 10 tillers (stems) in at least 10 different sites. If you are seeing mostly eggs, you should scout again in 5-7 days when some have hatched into small larvae. The eggs may be parasitized. Virginia’s threshold is 25 eggs + small larvae (total) per 100 tillers. At least half of that 25 should be larvae. An insecticide spray, if needed, should target the newly-hatched larvae. There is only one generation per year.
Commercial vegetable producers have a new tool to assist with integrated pest management (IPM) of diseases and insects in vegetables. MyIPM for Vegetables is the newest resource in the MyIPM app series (https://myipm.app/) for smartphones and smart devices. It currently includes modules for diseases and insects of cucurbits and tomatoes, and additional vegetable crops are planned to be added in the future. Modules contain images and descriptions of diseases and insects; information on available chemical, biological, and cultural management methods for each disease/insect; and tables of labeled fungicides and insecticides that include active ingredients, product names, FRAC/IRAC codes, efficacy, application rates, preharvest intervals (PHIs), and restricted-entry intervals (REIs). Links to additional resources may also be included.
App content is focused on commercial vegetable production in the southeastern U.S., but users outside the southeastern U.S. and home gardens may also find information in the app useful. The development of MyIPM for Vegetables content was led by vegetable entomology and plant pathology specialists from universities within the southeastern U.S. who are part of the Southeastern Vegetable Extension Workers (SEVEW). The SEVEW are also responsible for the popular Southeast U.S. Vegetable Crop Handbook (www.vegcrophandbook) that has been a key resource for commercial vegetable producers in the southeastern U.S. for over 20 years. Author and image credits for specific disease or insect profiles and pictures are available at http://myipm.app/vegetabltes.
MyIPM for Vegetables is not intended to replace product labels. It is meant to be a tool to help vegetable producers make informed IPM decisions. Pesticide users should always read and follow label instructions prior to use. Product labels may change. Product rates may differ depending on the site of application (e.g., field or greenhouse) or type of application (e.g., foliar-applied or soil-applied. Check product labels for additional instructions, precautions, and/or restrictions not listed in the app. Also, check the state registration status of products prior to purchase and use; products may not be registered for use in all states.
MyIPM for Vegetables is free to download for Apple (Apple Store) and Android devices (Google Play). Content is downloaded directly to phones/devices; an Internet connection or cellular signal is not required to access content once it is downloaded. Updates, however, do require an Internet connection or cell signal, and notifications will pop up when updates for downloaded modules and the appropriate Internet/cell connection is available. The MyIPM series began with MyIPM Fruit & Nut that was originally developed by Clemson University in 2012 for peaches and strawberries; the app has since expanded to include other small fruits, tree fruits, and pecans. Other apps in the series include MyIPM Row Crops and MyIPM Hawaii. The Southern Region IPM Center maintains the databases for the MyIPM series apps.
Acknowledgement
This work is partially supported by the Southern IPM Center (Project S23-043) as part of the USDA National Institute of Food and Agriculture Crop Protection and Pest Management Regional Coordination Program (Agreement No. 2022-70006-38002).
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Prepared by Dr. Rebecca A. Melanson, Associate Extension Professor, Plant Pathology, Central Mississippi Research and Extension Center; Dr. Thomas Kuhar, Department of Entomology, Virginia Tech; Dr. Tom Bilbo, Coastal Research and Education Center, Clemson University; and Ms. Inga Meadows, Department of Entomology and Plant Pathology, North Carolina State University.
EPA has finally issued a statement on the revocation of tolerances for chlorpyrifos. For this year, 2024, chlorpyrifos can be used on all product labeled crops. In 2025 and beyond, it will only be allowed on 11 specific crops; alfalfa, apple, asparagus, cherry (tart), citrus, cotton, peach, soybean, strawberry, sugar beet, and wheat (spring and winter). However, there will be further state restrictions on those 11 tolerances coming soon (e.g. chlorpyrifos will only be allowed on tart cherries in MI).
———- Forwarded message ———
From: U.S. EPA Office of Chemical Safety and Pollution Prevention oppt.epa@public.govdelivery.com
Date: Fri, Feb 2, 2024 at 1:23 PM
Subject: EPA Update on the Use of the Pesticide Chlorpyrifos on Food
To: dlfrank@vt.edu
EPA Update on the Use of the Pesticide Chlorpyrifos on Food
The U.S. Environmental Protection Agency (EPA) is issuing an update on the use of the pesticide chlorpyrifos on food.
Chlorpyrifos is an organophosphate insecticide used for a large variety of agricultural uses, including soybeans, fruit and nut trees, broccoli, cauliflower, and other row crops, as well as non-food uses. In a final rule issued in August 2021, EPA revoked all tolerances for chlorpyrifos, which establish an amount of a pesticide that is allowed on food. This action effectively stopped the use of the pesticide chlorpyrifos on all food and animal feed. EPA took this action in response to an April 2021 order from the U.S. Court of Appeals for the Ninth Circuit for the Agency to issue—within 60 days—a final rule addressing the use of chlorpyrifos in food or feed crops, without taking public comment or engaging in “further fact-finding.”
That tolerance revocation rule was challenged by a chlorpyrifos registrant and several grower groups in the U.S. Court of Appeals for the Eighth Circuit. On November 2, 2023, the Eighth Circuit issued a ruling vacating EPA’s final rule and sending the issue of chlorpyrifos tolerances back to EPA for further proceedings. The ruling did not include a timeframe or specific instructions for EPA to take a final action on the use of chlorpyrifos in food or feed crops without public comment.
EPA is issuing a technical correction in the Federal Register that changed the Code of Federal Regulations to reflect the Eighth Circuit’s decision. The Eighth Circuit’s mandate issued on December 28, 2023, finalized the court’s judgment and vacated the Agency’s 2021 rule revoking chlorpyrifos tolerances.
Since the tolerances are currently in effect, growers can now use currently registered chlorpyrifos products on all crops with reinstated tolerances, consistent with directions for use on those product labels. However, such uses may be subject to restrictions by individual states.
The Eighth Circuit’s decision stated that EPA should have considered modifying the tolerances in addition to complete revocation and noted that the Agency had “identified 11 specific candidates” of food and feed crop uses whose tolerances could be modified in a Preliminary Interim Decision EPA issued in 2020. Thus, the Agency expects to expeditiously propose a new rule to revoke the tolerances for all but 11 uses with additional restrictions for geographic location and rate of application to address safety of the tolerances, and potential restrictions for farmworker and other vulnerable populations, and vulnerable species and their habitats. Those 11 uses are: alfalfa, apple, asparagus, cherry (tart), citrus, cotton, peach, soybean, strawberry, sugar beet, wheat (spring), and wheat (winter). These 11 uses were identified in the December 2020 Chlorpyrifos Proposed Interim Decision and represented about 55% of the total chlorpyrifos usage (average annual pounds applied) on agricultural commodities between 2014-2018.
EPA is also engaged in discussions with registrants of chlorpyrifos products to further reduce exposures associated with these 11 uses of chlorpyrifos. EPA will also consider the 2020 Proposed Interim Decision and public comments received on that document.
At this time, any existing final cancelation orders, including any terms for sale, distribution, and use of existing stocks of products subject to those cancelation orders and related return programs for chlorpyrifos products, remain in place, unless and until amended by EPA.
EPA will continue to update the public as it evaluates and takes any actions related to chlorpyrifos use.
For more information, view the Federal Register Notice.
Peanut Burrower Bugs (Pangaeus bilineatus) have been collected and identified, by the Virginia Tech Insect Identification Laboratory, on the Tidewater AREC farm. Peanut burrower bugs are a subterranean pests that feed on pods and pegs of developing peanuts. Burrower bugs have most likely been around for a while but Lorsban (active ingredient is chlorpyrifos) was controlling their populations. Since the removal of Lorsban (chlorpyrifos) from market shelves, there are no effective chemical controls for producers. Damage caused by the peanut burrower bugs looks similar to stink bug damage. This damage is only seen when peanuts are shelled. The skin is removed at buying points by graders: The insect does not leave an indicator of damage on the shell of the peanut. Peanut burrower bug is more of an issue in hot dry years, and they are just as sporadic as southern corn rootworm.
In terms of prevention, there is no chemical control with the loss of lorsban. Some producers have gone back to using a moldboard plow and completely turning over the soil. Some producers have been planting earlier hoping for a thicker hull development earlier in the season. Damage is minimal in Suffolk, VA, but it is something to keep in mind.
