Fruit Pest News
Volume 10, No. 7 May 18, 2009
An 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. Current Conditions and Pest Reports
2. Mancozeb Section 18 Status
3. Fungicide Supplies
4. Grape Black Rot Infection Periods Since April 1
5. Label Changes for Danitol
6. Seed Treatment Insecticide for Cucurbits
7. Pheromone Trap Catches
1. Current Conditions and Pest Reports
We are currently experiencing a break from the two and a half week period of rain. Perennial crops may soon receive sprays of protection products that were washed off by the rains, while most annual crops have not even been planted.
Cucurbit downy mildew has not been reported outside the state of Florida thus far. Planting of cucurbit crops has been hampered by the rainy weather that has occurred in most areas other than Florida. Our sentinel plots in Tennessee have not yet been planted.
Late blight has been reported on tomatoes in northern Alabama. This disease could be a threat until the weather becomes hot and dry. Maintain good fungicide coverage of tomatoes and potatoes.
Recent first reports for the year: cutworms on tomato, Claiborne County, May 4; pear leaf blister mite, Jackson County, May 4; apple scab, Davidson County, May 6; Cercospora leafspot of turnip, May 15, Lincoln County. (SB)
2. Mancozeb Section 18 Status
It appears that the multi-state effort to obtain Section 18 labels for mancozeb on peppers has died. A Section 3 (federal) label for this purpose is still in the works, but probably will not be granted until late in the growing season. If pepper growers can locate any maneb, it can be used. An EBDC such as maneb or mancozeb is needed to enhance the bacteria-controlling property of copper. (SB)
3. Fungicide Supplies
Fungicide prices are higher this year for several reasons. Dow closed its Dithane production plant in Texas last fall for upgrading, and it has not yet reopened. The resulting shortage put pricing pressure on all EBDC fungicides, such as other mancozebs, Polyram, and maneb (where maneb can be found). Other fungicides are also seeing higher prices as shortages are occurring due to increased demand for fungicides in other countries and BASF's decision to cut production of Pristine by 50 percent. In addition, some strobilurin fungicides are being used on corn and soybeans for purposes other than disease control, e.g., enhanced yield. All of this may create a chain reaction through the fungicide industry.
The effect of these price increases may be to discourage use of fungicides. It would be a mistake to short-change a proven production tool. Try to make the most of your disease control dollar by using the products efficiently, i.e., at times of greatest need. Base your spray intervals on rainfall. There is no need to spray every seven days during periods of dry weather. Also, avoid using strobilurins when protectants will do. Source: Fruit Growers News, May, 2009 (SB)
4. Grape Black Rot Infection Periods Since April 1
Infection periods since April 1 are presented below. The weather data upon which this information is based was collected on a Spectrum WatchDog system placed in Nashville, TN. This information may familiarize you with this method of timing the application of fungicides in an effort to improve control while reducing the number of sprays. Each disease is based on a different "model," or system of predicting infection. Both models are based on the length of time the leaves stay wet at each temperature. They can be used to apply curative fungicides after infections occur or, by entering weather forecasts, to time fungicide applications for best effect. (SB)
|
Date, 2009 |
High temp |
Low temp |
Wet hours* |
Risk level |
|
Apr 19 |
63 |
53 |
19.0 |
1.72 |
|
Apr 20 |
69 |
49 |
7.0 |
2.07 |
|
May 1 |
75 |
59 |
22.0 |
2.80 |
|
May 2 |
65 |
59 |
12.5 |
4.19 |
|
May 3 |
63 |
58 |
21.0 |
2.28 |
|
May 4 |
70 |
55 |
17.5 |
3.83 |
|
May 15 |
88 |
60 |
10.0 |
1.34 |
|
May 16 |
83 |
60 |
7.0 |
1.12 |
*Hours above a threshold level of wetness.
5. Supplemental Label for Danitol 2.4 EC Spray
Danitol is now labeled for
use on stone fruit, caneberries (under the berries section), tree nuts and several
other uses. Pests listed in the stone fruit section include European red mite, twospotted
spider mite, green fruitworm, obliquebanded leafroller, redbanded leafroller, peach
twig borer, variegated leafroller, southern green stink bug, green stink bug and
several others. On caneberries, listed pests of note include twospotted spider mites
and Japanese beetles. There is a 3 day pre-harvest interval.
A few of the
listed pests on the label for tree nuts include pecan nut casebearer, shuckworm,
green stink bug, European red mite, and twospotted spider mite. Also, additional
pests have been added to the label for fruiting vegetables, grape, pea, and pome
fruit. On fruit vegetables and also for pea (succulent), green stink bug and southern
green stink bug have been added. On grape, plum curculio has been added. On pome
fruit, green stink bug, southern green stink bug, and periodical cicada have been
added. (FH)
6. Seed Treatment Insecticide for Cucurbits
Syngenta Seed
Care has a new insecticide seed treatment for cucurbits that targets early-season
insects. This insecticide component of FarMore Technology is designed to protect
cucurbits from aphids, cucumber beetles, flea beetles, leafminers, whiteflies, wireworms,
and seedcorn maggots. The FarMore Technology platform also provides broad-spectrum
fungicidal protection against Fusarium, Pythium, and Rhizoctonia. The seed treatment,
known as DI-400, must be applied by the seed company and is not available for
on-farm application. (FH, SB)
7. Pheromone
Trap Catches and Biofixes (FH)
Nashville (Davidson County) Pheromone Trap
Catches for 2009
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), beet armyworm
(BAW), squash vine borer (SVB), fall armyworm (FAW)
| OFM | RBLR | OBLR | CM | GBM | VLR | BCW | DBM | AW | CL | BAW | SVB | FAW | |
|
3-13 (Put out RBLR trap) |
-- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| 3-20 | -- | 29* | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| 3-23 | -- | 14 | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
|
3-30 (put out BCW trap) |
-- | 9 | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
|
3-31 (put out OFM, CM, VLR, OBLR traps) |
-- | 10 | -- | -- | -- | -- | 0 | -- | -- | -- | -- | -- | -- |
| 4-2 | 4** | 2 | 0 | 0 | -- | 0 | 0 | -- | -- | -- | -- | -- | -- |
|
4-3 (put out AW trap) |
-- | -- | -- | -- | |||||||||
|
4-8 (put out GBM, DBM, BAW, FAW, SVB, CL traps) |
12 | 19 | 0 | 0 | -- | 0 | 2 | -- | 4 | -- | -- | -- | -- |
| 4-13 | 9 | 17 | 0 | 0 | 4*** | 0 | 0 | 0 | 7 | 0 | 0 | 0 | 0 |
| 4-20 | 4 | 7 | 0 | 0 | 5 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| 4-27 | 6 | 0 | 0 | 0 | 16 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 5-4 | 2 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| 5-11 | 0 | 0 | 4**** | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
| 5-18 | 5 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
* Biofix for RBLR in Davidson County estimated as prior to March 20 (trap not
out early enough).
**Biofix for OFM in Davidson County was April 2.
***Biofix
for GBM in Davidson County was April 13.
****Biofix for OBLR in Davidson County
was May 11.
Putnam County Pheromone trap Catches for 2009
Tufted Apple Bud Moth (TABM)
| OFM | RBLR | OBLR | CM | VLR | TABM | |
| 3-16 | -- | 10* | -- | -- | 0 | -- |
| 3-18 | -- | 31 | -- | -- | 0 | -- |
| 3-20 | -- | 2 | -- | -- | 0 | -- |
| 3-23 | -- | 2 | -- | -- | 0 | -- |
| 3-25 | -- | 0 | -- | -- | 0 | -- |
| 3-27 | -- | 6 | -- | -- | 0 | -- |
| 3-30 | -- | 11 | -- | -- | 0 | -- |
|
4-1 (put out OBLR, TABM traps) |
||||||
| 4-3 | -- | 10 | 0 | -- | 0 | 0 |
|
4-10 (put out OFM trap) |
-- | 11 | 0 | -- | 0 | 0 |
| 4-13 | 4 | 3 | 0 | -- | 0 | 0 |
|
4-17 (put out CM trap) |
12 | 9 | 0 | -- | 0 | 0 |
| 4-20 | 10 | 0 | 0 | 2** | 0 | 0 |
| 4-22 | 4 | 0 | 0 | 0 | 0 | 1 |
| 4-24 | 7 | 2 | 0 | 2 | 0 | 2*** |
| 4-27 | 4 | 0 | 0 | 1 | 0 | 0 |
| 5-1 | 5 | 0 | 0 | 0 | 0 | 0 |
| 5-8 | 11 | 0 | 0 | 1 | 0 | 14 |
| 5-15 | 1 | 0 | 0 | 0 | 0 | 15 |
*Biofix for RBLR in Putnam County estimated as prior to March 16 (trap not out
early enough).
**Biofix for CM in Putnam County was April 20.
.**Biofix for
TABM in Putnam County was April 24.
Obion County Pheromone Trap Catches for 2009
| VLR | |
| 5-1 | 3* |
| 5-12 | 42 |
*Biofix for VLR in Obion County was May 1.
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
Soil, Plant and Pest Center
5201 Marchant Drive
Nashville, TN 37211
Copyright 2009 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.
Programs in agriculture and natural resources, 4-H youth development, family and consumer sciences, and resource development. University of Tennessee Institute of Agriculture, U.S. Department of Agriculture and county governments cooperating. UT Extension provides equal opportunities in programs and employment.