Fruit Pest News
Volume 8, No. 13 June 5, 2007
A weekly, online newsletter whose goal is to provide all interested persons with timely information on diseases and insects of commercial fruit and vegetable crops in Tennessee.
Text appearing in blue or red can be clicked to link to other web sites. Be aware that much of the linked information is produced in other states and may not be applicable to Tennessee.
In This Issue:
1. First Reports for the Year in TN
2. Tomato Spotted Wilt Reports
3. Status of the Commercial Vegetable Disease, Insect and Weed Control Guide
4. Tomato Spray Program for Disease Control
5. Peachtree Borer and Lesser Peachtree Borer
6. Japanese Beetle and Green June Beetle Adults
7. Matted-Row Strawberry Disease Control After Harvest
8. Pheromone Trap Catch Reports
1. First Reports for the Year in TN
Japanese beetles - Henry and Williamson Counties, June 2.
2. Tomato Spotted Wilt Reports
Davidson County - May 21. Madison County - May 22. Wayne County - May 23. Davidson County - May 29. Decatur County - May 30. Fayette County - June 5. Humphreys County - June 5.
All reports have been from home gardens or research centers - none from commercial fields, yet. Please give us your spotted wilt reports. We'd like to monitor its distribution. Tomatoes are the most common hosts, but spotted wilt also occurs on peppers, tobacco, and certain ornamentals. If you need help in confirming a suspected case, don't hesitate to send us some images through our distance diagnostics system, available at all county Extension offices. (SB)
3. Status of the Commercial Vegetable Disease, Insect and Weed Control Guide
The Commercial Vegetable Disease, Insect and Weed Control guide, PB1282, is currently being printed. It will be available at no cost again this year. The weed section has been reinstated. The electronic version of PB 1282 is available on our web site at http://www.utextension.utk.edu/publications/pbfiles/PB1282.pdf (SB)
4. Tomato Spray Program for Disease Control
Generally, a spray program of 7 to 10-day intervals is needed for control of diseases in tomatoes, although the intervals between sprays could be lengthened to 14 days in the current dry weather. Appreciate the fact that, even though your crop may not have received any rain to wash off the protective residue, much new foliage can emerge in 14 days -- It is not protected against the effects of a sudden rain.
The strobilurin fungicides, Quadris or Cabrio, provide unmatched control of early blight. They must be alternated with unrelated fungicides. Prior to harvest, your alternation material can be either an EBDC (maneb or mancozeb) or chlorothalonil. The EBDC's are cheaper than chlorothalonil, and they double as a synergist for copper against bacterial diseases.....chlorothalonil does not. However, the 5-day PHI for the EBDC's interferes with the harvest schedule, and a switch to chlorothalonil is necessary during harvest.
The strobilurins are limited to 6 applications per crop, and the Quadris label prohibits its use prior to 21 days after transplanting. With these restrictions in mind, it is suggested that you begin with an EBDC within a week or two after planting. If you expect bacterial disease problems based on history, add a bacterial control product to each application. It is suggested that you use more than one bacterial control product and alternate them in the schedule. Copper, Actigard, and Agri-Phage are the choices. These materials can be omitted if no problems with bacterial diseases are expected. If such problems should appear later, copper and Agri-Phage can be added at that time. Actigard would not be as suitable because of the lead-in time needed before activation of resistance to the disease.
Specialized control products may be needed if unexpected diseases occur, such as late blight, gray mold, or timber rot. These materials can be found in the spray guide. Spray volume should begin at about 20 gallons per acre, increasing as the plants grow, up to about 100 gallons per acre. Drop nozzles should be used, with the number of nozzles depending on plant height. (SB)
5. Peachtree Borer and Lesser Peachtree Borer
Another option for peachtree
borer and lesser peachtree borer not addressed in the last newsletter is the use
of pheromone mating disruption. Isomate-L pheromone ties can be used for both of
these pests. With careful monitoring by IPM professionals, it will be often feasible
to eliminate the handgun chlorpyrifos application. (FH)
6. Japanese Beetle and Green
June Beetle Adults
The adult Japanese beetles have been somewhat slow to emerge,
possibly because of the dry, hard soil. Two reports of adult Japanese beetles this
past weekend came from Henry and Williamson Counties. I have not seen green June beetles yet, but
they should be emerging later this month. While the Japanese beetle is can skeletonize
leaves, both of these pests can feed directly on fruit. On stone fruit, all fruit
feeders can spread pre-harvest brown rot, especially in wet weather. In the pre-harvest
period, imidacloprid (Provado 1.6F) provides good control of green June beetles,
Japanese beetles and rose chafer, but it does not control some other common pre-harvest
stone fruit insects.
On blackberry and raspberry during the cover sprays,
control Japanese beetles and green June beetles with malathion (1 day PHI) or carbaryl
(Sevin) with a 7 day PHI. In bunch grapes during closing, control these pests with
Sevin (7 day PHI), malathion (3 day PHI), Imidan 70 WP (7 day PHI for 11/3 lb/acre
or less, 14 day PHI for greater than 11/3 lb/acre), Pyrellin EC, Pyrellin 2L and
Pyrellin 2S (12 hour PHI for Pyrellin). Treat muscadines during summer cover sprays
with Imidan 70W (14 day PHI) or Danitol 2.4 EC (21 day PHI). Beware of heavy emergence
and migration to blocks with ripe fruit after rains. Sevin 80 S (7 day PHI) or Provado
1.6F (3 day PHI) can be used on blueberry near harvest time. (FH)
7. Matted-Row Strawberry Disease Control After Harvest
Harvest has
wound down, and now it is time to take steps to produce a healthy bed of plants for
next year's crop. Proper renovation is the most important step in producing a vigorous
crop. When new growth emerges after renovation, fungicide applications may be necessary,
especially in rainy weather. Anthracnose is the greatest threat, since this disease
can prevent bed fill and can debilitate established plants. However, the runner
phase of anthracnose, which affects stolons, petioles and crowns, is difficult
to control. Efforts to control anthracnose on these vegetative parts of the
plant, even with effective fungicides such as Quadris and Switch, may lead to disappointing results.
Resistant varieties such as Delmarvel and Bish do not need control measures.
Phomopsis leaf blight and leaf scorch can be problems in hot, rainy weather, whereas common leaf spot is a problem on certain varieties in cool seasons. Below is a summary of the results I have obtained with field trials on the leaf spot diseases.
Summary of Strawberry Foliar Fungicide Trials
Amount of Disease Control
(0=none, *****=excellent)
|
Product |
Leaf Blight |
Leaf Spot |
| Topsin M |
*** |
*** |
| Captan, Thiram |
** |
*** |
| Nova |
**** |
**** |
| Abound |
*** |
**** |
Please note the following:
Pheromone Trap Catches for 2007
Nashville
(Davidson County)
Oriental fruit moth (OFM), redbanded
leafroller (RBLR), obliquebanded leafroller (OBLR), codling moth (CM), grape berry
moth (GBM), variegated leafroller (VLR), black cutworm (BCW), diamondback moth (DBM),
armyworm (AW), cabbage looper (CL)
| OFM | RBLR | OBLR | CM | GBM | VLR | BCW | DBM | AW | CL | |
| 2-22 (caught one RBLR in last year's trap) put out new trap | -- | 1 | -- | -- | -- | -- | -- | -- | -- | -- |
| 2-26 | -- | 0 | -- | -- | -- | -- | -- | -- | -- | -- |
| 2-28 | -- | 1* | -- | -- | -- | 1 | -- | -- | -- | -- |
| 3-2 | -- | 3 | -- | -- | -- | 0 | -- | -- | -- | -- |
| 3-12 | -- | 50 | 0 | -- | -- | 0 | -- | -- | -- | -- |
| 3-14 (Put out OFM, CM, OBLR, BCW) | -- | 26 | -- | -- | -- | 0 | -- | -- | -- | -- |
| 3-20 | 0 | 33 | 0 | 0 | -- | 0 | 0 | -- | -- | -- |
| 3-21 | 1 | 7 | 0 | -- | -- | 0 | 0 | -- | -- | -- |
| 3-26 | 20** | 34 | 0 | -- | -- | 0 | 0 | -- | -- | -- |
| 3-27 (put out AW trap) | 8 | 4 | 0 | 0 | -- | 0 | 0 | -- | -- | -- |
| 3-30 | 12 | 16 | 0 | 0 | -- | 0 | 0 | -- | 0 | -- |
| 4-2 | 18 | 18 | 0 | 0 | -- | 0 | 0 | -- | 1 | -- |
| 4-3 (put out DBM, GBM, CL) | 10 | 1 | 0 | 0 | -- | 0 | 0 | -- | 0 | -- |
| 4-5 | 11 | 0 | 0 | 0 | 4*** | 0 | 0 | 0 | 0 | 0 |
| 4-10 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 4-17 | 2 | 1 | 0 | 0 | 2 | 0 | 0 | 0 | 0 | 0 |
| 4-23 | 28 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 4-25 | 8 | 0 | 2**** | 0 | 0 | 0 | 0 | 4^ | 0 | 0 |
| 4-30 | 5 | 0 | 6 | 0 | 0 | 0 | 0 | 1 | 0 | 0 |
| 5-21 | 3 | 2 | 6 | 0 | 0 | 0 | 0 | 4 | 5 | 5 |
| 5-29 | 6 | 9 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 6-4 | 7 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 |
* Biofix for RBLR in Davidson County was February 28.
** Biofix for OFM in
Davidson County was March 26.
*** Biofix for GBM in Davidson County was April
10.
**** Biofix for OBLR in Davidson County was April 25.
^ Biofix for DBM
in Davidson County was April 25.
Bradley County
| OFM | CM | |
| 3-26 | 1 | 0 |
Putnam County
| OFM | RBLR | OBLR | CM | VLR | |
| 3-19 | 1 | 9* | 0 | 4*** | 0 |
| 3-21 | 1** | 3 | 0 | 2 | 0 |
| 3-23 | 2 | 6 | 0 | 1 | 0 |
| 3-26 | 2 | 15 | 0 | 2 | 0 |
| 3-28 | 4 | 7 | 0 | 1 | 0 |
| 3-30 | 2 | 14 | 0 | 0 | 1 |
| 4-2 | 6 | 32 | 0 | 0 | 0 |
| 4-6 | 2 | 28 | 1 | 1 | 0 |
| 4-13 | 0 | 2 | 1 | 0 | 0 |
| 4-20 | 0 | 7 | 0 | 0 | 0 |
| 4-23 | 0 | 1 | 1 | 2 | 1 |
| 4-25 | 0 | 0 | 1**** | 0 | 0 |
| 4-27 | 0 | 1 | 3 | 0 | 0 |
| 5-4 | 0 | 1 | 5 | 6 | 2 |
| 5-11 | 0 | 15 | 0 | 0 | 1 |
| 5-25 | 0 | 24 | 0 | 0 | 0 |
| 5-28 | 0 | 15 | 0 | 2 | 0 |
| 6-2 | 0 | 26 | 0 | 0 | 0 |
*Biofix for RBLR in Putnam County estimated as March 2 (trap not out early enough).
**Biofix
for OFM in Putnam County March 21.
***Waiting to verify biofix for CM, many unknown
moths being caught in these traps that can easily be mistaken for CM.
**** Biofix
for OBLR in Putnam County for OBLR was April 25.
Obion County
| OFM | RBLR | OBLR | CM | VLR | |
| 3-19 | 0 | 17* | 0 | 0 | 0 |
| 3-26 | 5** | 89 | 0 | 1 | 0 |
| 4-11 | 0 | 0 | 0 | 0 | 0 |
| 4-16 | 2 | 0 | 0 | 0 | 0 |
| 4-23 | 0 | 0 | 0 | 0 | 1 |
| 4-30 | 7 | 0 | 10*** | 0 | 17**** |
| 5-7 | 10 | 0 | 3 | 0 | 2 |
| 5-17 | 11 | 3 | 7 | 1 | 14 |
| 5-21 | 0 | 7 | 1 | 0 | 5 |
| 5-29 | 0 | 5 | 0 | 0 | 0 |
| 6-4 | 2 | 7 | 1 | 0 | 2 |
* Biofix for RBLR in Obion County estimated to be on March 2 (trap not out early
enough).
** Biofix for OFM in Obion County on March 26.
*** Biofix for OBLR
in Obion County on April 30.
**** Biofix for VLR in Obion County on April 30.
The Fruit Pest News URL is: http://web.utk.edu/~extepp/fpn/fpn.htm
Contacts:
Steve Bost, Professor and Extension Plant Pathologist
Frank Hale, Professor and Extension Entomologist
Both authors available at:
615-832-6802
fax 615-781-2568
Plant and Pest Diagnostic Center
5201 Marchant Drive
Nashville, TN 37211
Copyright 2007 The University of Tennessee. All rights reserved. This document may be reproduced and distributed for nonprofit educational purposes provided that credit is given to University of Tennessee Extension.
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