The Virginia Tech Eastern Shore Agricultural Research and Extension Center Annual Research Field Day will be held on Tuesday, June 28, 2011, in Painter, Virginia. This year our field day will feature plot research demonstrating methyl bromide alternatives for vegetable production along with nutrient, weed, disease, insect and general production techniques for polyethylene mulch systems, tomatoes, potatoes, corn, cotton, soybeans and more. Registration will begin at 8:00 AM with field tours beginning at 9:00 AM. A complimentary lunch will begin at noon. For questions or assistance with special needs, please call 757-414-0724.
Plant bug in cotton, product choice and restriction on Bidrin use
We are seeing a few more fields than usual with plant bugs and damage. According to Johnny Parker with Commonwealth Gin, the number of fields reaching the threshold is about 3-5 percent, and that is based on his surveying about 100 fields over the past week. Since fields are still in the pre-bloom stage, thresholds are based primarily on square retention: Do not let fields drop below 80%. Plant bug damage is distinct and pretty easy to see. Bugs prefer to feed on the small pinhead terminal squares causing them to turn black and shed. You can find the tiny black squares (hit the ‘More’ button to see the image) or the scar where the square was shed. We do not have a lot of experience doing insecticide trials with plant bugs so I called one of my colleges in a state that deals with a lot of plant bug pressure. He recommends using only the insecticides in the neonicotinoid class (e.g., Admire Pro @ 0.9-1.7 oz, Belay @ 3-4 oz, Centric, @ 1.25-2.0 oz) and that they are effective. For resistance management and fear of flaring secondary pests, they recommend avoiding use of either pyrethroids (e.g., Bifenthrin, Karate, Baythroid) or organophosphates (e.g., Bidrin, Orthene). And, he reminded me that Bidrin CANNOT be used during this pre-bloom period. These are the statements on the labels (Bidrin: Early Season—Emergence to pre-square; Late Season—First bloom to 30 days prior to harvest) (Bidrin XP: Use only after cotton reaches the ‘First Bloom’ stage of growth).
Additional information: tpb-square-damage-herbert-doc
Early corn earworm activity in Virginia subsides
After some higher than usual corn earworm pest activity for the spring in Virginia, moth catch at traps has subsided. Raef Parker in the Northern Neck of Virginia is maintaining a couple corn earworm pheromone traps. A couple weeks ago he was catching several moths per night, but this week, the traps have gone silent, which is a good indication that new eggs of this pest are not being laid. Typically, corn earworm pest activity picks up dramatically in mid-July. So, hopefully, we’re in the clear for a little while anyway.
TK
Corn earworm moth black light trap averages for the week ending June 23, 2011
Most black light trap operators have their traps up and running now. The Tidewater AREC trap in Suffolk, VA captured an average of 2.6 corn earworm moths per night, while Neil Clark (Virginia Cooperative Extension, Southampton County) reported zero corn earworm moths for this week. Please click “More” to view the summary table. Additional information: blacklight-table-11-docx
Stink bug update
Following a bit of local news coverage about the brown marmorated stink bug (BMSB) and its potential to become a problem in our coastal plain region, I have received numerous contacts from local homeowners/gardeners. To date, of those that have been able to provide insect samples, none have been the dreaded critter. Most have been either our native brown stink bug, or the squash bug, which is beginning to attack squash plants throughout the region. Although damaging, we understand these insects and know how to manage them…as opposed to BMSB which would pose a much bigger challenge. So for now, the good news is that BMSB has not been reported attacking crops in our area…yet. Locals are encouraged to send in suspected samples for ID (Attn: Ames Herbert, Tidewater AREC, 6321 Holland Road, Suffolk, VA, 23437). We recommend that folks put any bugs-in-question into a zip-lock sandwich bag and into the freezer. When mailing, just pad them to prevent breakage during the delivery process.
Corn earworm update
Although we are beginning to catch a few more moths than last week, we are still between generations. If things go according to previous patterns, the second generation will peak at a time to coincide with when field corn is developing ears. Some fields are beginning to tassel, so it won’t be long. We will be tracking and posting our trap catch and AVT (adult vial pyrethroid test) results weekly.
Tomato spotted wilt virus (TSWV) in peanuts and home garden tomatoes
Incidence of TSWV is increasing in the peanut crop. We have the advantage of having a lot of peanut thrips trials evaluating varieties and many insecticide control options where we are also able to rate TSWV severity. Hopefully, we will find the most effective alternatives for minimizing both thrips and the disease. We are also getting reports from home gardeners that tomato plants are showing disease symptoms. When disease symptoms begin to express in a plant, there is essentially nothing that can be done to decrease the severity. Some feel that removing infected tomato plants will prevent, or at least minimize the risk of transmission to other plants. Maybe, but the transmission has to occur from adult thrips that acquired the virus by feeding on infected plants while in the larval stage. An insecticide protection regime designed to control thrips can help a lot in reducing the spread of the virus from plant to plant.
Spider mites in soybean
We diagnosed a very heavy spider mite infestation on a soybean seedling sample from the Northern Neck area but are not hearing of widespread problems…yet. Although some areas got some decent amounts of rainfall over the last weekend, some areas are still pretty dry with conditions very conducive to spider mite outbreaks. If treatments are needed, Dimethoate is likely the best product choice as it has efficacy against adults and immatures, and some systemic activity. But, according to one of the suppliers with Cheminova, it is important to be certain the product is newly manufactured and has been stored properly. If the product is old or has been exposed to extreme high and low temperature fluctuations, it can be ‘denatured’ which greatly reduces its efficacy.
New 2ee label for use of acephate on field borders for stink bugs
United Phosphorus, Inc (UPI) has issued a FIFRA Section 2(ee)
recommendation with Acephate 97UP for the suppression of brown marmorated
stinkbugs for field borders, fence rows, ditch banks and borrow pits. The
states include Delaware, Pennsylvania, Virginia, New Jersey, West Virginia
and Maryland. Attached is the 2(ee) recommendation below. Should you have
questions please feel free to contact:
Tony Estes
United Phosphorus, Inc.
Cell Phone: 864-202-7526
tony.estes@uniphos.com
Click more for attached file of 2ee label.
Additional information: 2011-06-07-2-ee-acephate-97up—bmsb-field-borders-pdf
Stink bugs in field corn
Recent reports of stink bugs feeding in the whorl of field corn have come to my attention. There was no word on what species of stink bug they were, or how extensive the damage is, but whichever stink bug it is, their piercing-sucking mouthparts can reach the growing tip of young corn plants. Insecticides labeled to control stink bugs in field corn are available and can be accessed from Virginia Tech’s Cooperative Extension Pest Management Guide for field crops. Disclosure, I don’t have any efficacy data on stink bug control in field corn. This is largely due to the sporadic nature of these pests over the years.This picture has changed with the recent invasion of the brown marmorated stink bug in Virginia. That said, I tend to lean toward FMC products Hero 15EC and Stallion 15EC, which combine two insecticides. Hero contains two pyrethroids: bifenthrin and zeta-cypermethrin and Stallion contains one pyrethriod and one organophosate: zeta-cypermethrin and chlorpyrifos. One note of caution, if you’re going to use either of these products, I recommend using the high rates, because brown marmorated stink bugs have the tendency to re-invade. Also, the next potential threat to field corn from brown marmorated, or other stink bugs, is when corn begins to enter the reproductive stage. Contact: Rod Youngman, youngman@vt.edu, 540-231-9118 (office), 540-357-2558 (cell).