Vegetable Press

Vol. 00 No. 09 September 18, 2000

Fall Flower & Garden Fest Planned for October

Dr. Rick Snyder, Vegetable Specialist

The 22nd annual Fall Flower & Garden Fest is planned for October 13 & 14 (Friday & Saturday) at the Truck Crops Experiment Station in Crystal Springs, just 25 miles south of Jackson. Come see our 3 acre vegetable, flower, and herb gardens! Many educational exhibits are planned for you, including Garden Seminars all day, both days.

From Jackson, take I-55 south to exit 68, turn left, then follow US 51 south for a mile and a half. Look for the Fall Flower & Garden Fest sign, turn left and cross the tracks. There is ample parking on the grounds.

There is no admission charge. A variety of food vendors will be available for lunch and drinks.

For more information, call (601) 892-3731 or your local Mississippi State University Extension Office, or email to RickS@ext.msstate.edu. We also have a web site at http://www.msstate.edu/de pt/cmrec/fallgardenday.htm . A flyer is attached to this newsletter with more details.

Stink Bugs and Their Control

Dr. J. Pat Harris
Extension Entomologist

Conditions have been ideal for high stink bug populations this year. Green and brown stink bugs are generally our major problem. Damage is caused by nymphs (immatures) and adults sucking sap from the pods, buds, blossoms, fruits, and seeds. Removing liquid contents of the developing seeds causes them to become flattened and shriveled; fruits are deformed and dimpled.

 

Egg hatch occurs in about 5 to 7 days. After 5 nymphal instars (growth stages), the adult stage is reached about 6 weeks later, depending on species and weather conditions. Adults usually live 40 to 60 days during the summer. A new generation occurs every 5 to 6 weeks during the summer.

Control stink bugs when they first appear. Nymphs are less mobile and easier to control. All stages may be controlled with *methyl parathion, *Penncap M, Sevin XLR or 80 WP, or Endosulfan 3 EC, depending on the crop to be treated. If necessary, tank-mix Sevin and Endosulfan insecticides at label rates for added control. Check labels for rates, usages, precautions, and crop registration.

*Restricted pesticide

Squash Bug Control

Dr. J. Pat Harris
Extension Entomologist

Squash bugs attack all cucurbits or vine crops and have a preference for squashes and pumpkins. They suck sap from leaves, stems, and fruits causing leaves and vines fed upon to wilt rapidly, become blackened, and die.

Adults are brownish-black, flat-backed, and about 5/8 inch long. Egg clusters are usually found on the undersides of leaves in the angle formed by the veins. When freshly laid, eggs are yellowish-brown and turn dark brown as they approach hatching. They are usually laid in groups of a dozen or more. Eggs hatch into small nymphs which are strikingly colored green and crimson. All five nymphal instars and adults feed gregariously on plants.

When cucurbits first begin to produce "runners", squash bugs move into the fields. Because squash bugs are so difficult to control, insecticide should be applied on schedule. Insecticide should be applied at 5 to 6 day intervals until control is obtained. Thorough coverage is necessary.

Control them with *Asana XL; Sevin 50 WP, 80 WP, or XLR 4; or Endosulfan 3 EC. Refer to labels for crop registration, usages, and precautions.

*Restricted pesticide.

Leaf-footed Bug Control

Dr. J. Pat Harris
Extension Entomologist

Leaf-footed bugs, when full grown, are larger than stink bugs and more oblong in shape. They vary in color from brown to black, and have a white to light-yellow stripe across their mid-back. They damage plants in a way similar to stink bugs with piercing-sucking mouth parts.

Control leaf-footed bugs when they first appear. Nymphs are less mobile and easier to control. All stages may be controlled with *methyl parathion, *Penncap M, Sevin XLR or 80 WP, or Endosulfan 3 EC, depending on the crop to be treated. If necessary, tank-mix Sevin and Endosulfan insecticides at label rates for added control. Check labels for rates, usages, precautions, and crop registration.

*Restricted pesticide

Control of Cowpea Curculio

Dr. J. Pat Harris
Extension Entomologist

Southernpeas are often attacked by a small black beetle called cowpea curculio. Adult beetles feed on young pods, and females deposit eggs in small holes eaten through the pods. Eggs hatch into young, white, legless grubs that feed within the developing pods. Generally, there are two generations per season, with each generation from egg to adult requiring about thirty days.

 

First year peas in some areas may not have a problem with this insect. In areas where peas have been grown and/or have a history of curculio problems, insecticide application should begin when first pods are 2 inches long or less and continue for four applications at five day intervals. Spray using Endosulfan 3 EC at 2/3 to 1 1/3 quarts per acre. Allow three days between application and harvest. Spray for coverage. *Penncap M may also be used. Refer to labels for further information.

*Restricted use pesticide

Sweetpotato Weevil Control

Dr. J. Pat Harris
Extension Entomologist

Check your crop for sweetpotato weevils. Adults lay their eggs in stems and the grubs work down to the roots. Once in roots, the life cycle continues and roots may become riddled. The adult is a shiny, slender, snout beetle about _ inch long. The head, wing covers, and abdomen are blue-black. The segment behind the head (prothroax) and the legs are bright red.

We have a 24C (Special Local Need Label) for Imidan 70 WSP and Imidan 70 WSB labels for use in Mississippi this year. Apply 1 1/3 pounds per acre as needed, with up to five applications. Water pH should be 5.5 to 6.0 for best results. Thiodan will give suppression but not control of this pest. Apply as a foliar spray in 2.5 gallons of water per acre. Several applications may be necessary.

After sweetpotatoes are harvested, use Imidan 5 dust at 2-4 ounces per bushel when storing. Cover all surfaces using only one application. Be sure to wash sweetpotatoes before using. Legally, sweetpotatoes infested with weevils should not be moved from the farm until first cleared with the Division of Plant Industry. There is a quarantine on this pest.

 

Digital Imagery for Disease Diagnosis

Dr. David M. Ingram, Extension Plant Pathology Specialist, Central MS Research & Extension Center, Raymond, Mississippi

Proper management of vegetable crops requires timely decision-making regarding weed control, fertility, insect control, harvesting, and disease management. Advances in technology have made it possible to obtain larger amounts of information quickly and process it more accurately. Such things as the internet and e-mail have cut the amount of time spent obtaining information related to pesticides and fertilizers. Many publications are now going on-line, decreasing the time from the press to print and then to the reader. Growers can access some publications on the web, thus decreasing time from the press to the mailbox.

In the case of plant disease diagnosis, a great deal of time usually is consumed in the sampling procedure, mailing, and then the time spent in the lab for the scientist to determine the actual cause of the plant disorder. Then there is valuable time lost in returning the answer and suggested control procedures to the county agent or grower. In many cases, samples mailed over the weekend become contaminated with bacteria (especially if improperly packaged), which often rot the sample and make diagnosis impossible. Then the process is begun all over again, with more time lost. By the time the grower gets an answer-----well, you get my point.

There is now a tool plant pathologists, entomologists, other plant professionals, county agents and some growers are using to speed the process of diagnosing plant problems. This new tool is the use of "digital imagery". Digital cameras are becoming more common in households and will soon be as common as the personal computer. Digital cameras are available at most photo shops and retail stores at a cost of about $300. Digital cameras take images and store them as individual files in a format that the computer can read and display on the monitor as a picture. Some brands of digital cameras use standard 3.5-in floppy diskettes to store the image files. The diskettes have the capacity to store about 10-30 images depending on the resolution and the space each image occupies on the disk. Most computers have software programs capable of viewing the files. These stored files can then be e-mailed to a specialist who can view them immediately upon receiving the e-mail. The specialist can then determine the cause of the plant disorder and reply via e-mail to the sender the appropriate measures to take to control or prevent further problems.

All of this technology can speed diagnosis time to about an hour or so from the time the picture is e-mailed until the specialist responds with recommendations. However, this new system of "distance diagnosis" still has a few drawbacks. The first of these is the availability of digital cameras. Many county offices are now equipped with digital cameras and more are being purchased every day.

Soon, most county offices will have digital imagery capability. The second drawback is that digital images are not as clear as 35MM camera pictures. Once the images are downloaded onto a computer and opened for viewing, the pictures may need to be enlarged. Doing this often results in a "grainy" picture that makes it hard to determine causes of plant disorders ( the picture itself looks like a disorder). The third problem comes about with the distance the image is taken from the diseased plant. The closer the digital camera comes to the specimen, the more out of focus the image becomes. Viewing the image through the screen on the camera also becomes more difficult when the sunlight is directly in front of the camera causing shadows on the screen.

The resolution of digital cameras will undoubtedly become better over time. The following tips may help your county agent or specialist when taking digital images. First, take several pictures of the diseased specimen and from a couple of different angles. One image usually is not sufficient for accurate diagnosis. Take a close-up of the most severely affected plant part and then take one of the entire plant. This helps the specialist get an overall view of the problem. View the pictures you take, both in the field and on your computer before sending to the specialist. Some may not be in focus and will not be worth sending. It is a good idea to take an actual plant sample to send to the diagnostic lab. Wrap the specimen in a paper towel or newspaper and place in a paper sack. Wrapping plant specimens in wet paper and sealing in plastic bags speeds degradation of the sample by bacteria, making diagnosis difficult, if not impossible. County extension offices have publications on how to package plant samples for the diagnostic lab.

Digital imagery for distance diagnosis of plant health problems is a useful tool that will become more common in the future. The technology is being used now with a very high success rate. Time is being saved, but more importantly, decisions on plant health are being made when they count-----right now. Contact me or your county extension office for more details on the use of digital imagery for plant disease diagnosis.

Calendar of Coming Events _

Dr. Rick Snyder, Vegetable Specialist

September 22 & 23 - North Mississippi Garden Expo, at North Mississippi Research & Extension Center, Verona, Mississippi, 8:30 am to noon. For information, contact Dr. Kent Cushman at

(662) 566-2201.

October 13 & 14 - Fall Flower & Garden Fest, Truck Crops Experiment Station, Crystal Springs, MS, 9 am to 2 pm. For information, call (601) 892-3731 or your local Mississippi County Extension office, or email RickS@ext.msstate.edu.

Web site: http://www.msstate.edu/dept/cmrec/fallgardenday.htm

December 11-13 - 15th Annual Southeast Vegetable and Fruit Expo and Ag Tech 2000, at Sheraton Greensboro Hotel Four Seasons, Greensboro, NC. For information, contact Allan Thornton at (910) 592-7161, email to allan_thornton@ncsu.edu, or check the web site at www.soil.ncsu.edu/agtech2000.

Dr. Richard G. Snyder,

Vegetable Specialist

Truck Crops Research & Extension Center

Mississippi State University

P.O. Box 231

Crystal Springs, MS 39059

PHONE: _ (601) 892-3731

Fax: (601) 892-2056

Internet: RickS@ext.msstate.edu

 

Web Pages

Central Mississippi Research & Extension Center http://www.msstate.edu/dept/cmrec/

North Mississippi Research & Extension Center http://www.msstate.edu/dept/nmrec/

Greenhouse Tomato FAQ http://ext.msstate.edu/anr/plantsoil/vegfruit/tomato/ghtomato/faq.html/

Vegetable Resource Page
http://www2.msstate.edu/~ricks/

Organic Fruit and Vegetable Web Page
http://www.msstate.edu/dept/cmrec/organic/

Greenhouse Tomato Short Course
http://www.msstate.edu/dept/cmrec/GHSC.htm

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