From: Frank Louws, Assistant Professor, Department of Plant Pathology, NCSU
Based on a high incidence of anthracnose in North Carolina fields, an emergency exemption was obtained for the use of Quadris in problem fields. In certain regions of the state a significant portion of the fields had infected plants (for diagnosis and pictures see previous Pest Alert on March 31, 1999: alert13.html). No fruit rot has been noted to date but under favorable weather conditions (warm temperatures and rain, especially wind-driven rain) problem fields would have a high risk of fruit rot potential. We have isolated Colletotrichum acutatum from infected plants, an aggressive pathogen not controlled satisfactorily with current options available to strawberry producers. Therefore, Quadris has received an emergency exemption for North Carolina growers effective April 12, 1999.
Quadris is a protectant fungicide and should be applied prior to or in the early stages of disease development. Applications may be made by ground only. Use sufficient water volume for adequate coverage (a minimum of 20 gallons of water is recommended). Apply QUADRIS at 7 to 14 day intervals at 6.2 to 12.4 fl. oz./A. Applications can be made up to day of harvest. Use the higher rate when conditions for disease epidemics are severe. No more than 3 sequential applications of Quadris should be made before alternating with fungicides that have a different mode of action. Do not alternate or tank mix with fungicides to which resistance has developed in the pathogen population. (Quadris is extremely phytotoxic to certain apple varieties; extreme care must be used to prevent injury to apple trees.). Do not apply more than 4.6 pints of product per acre per crop (1.2 lbs a.i./A). A label is attached to this message and must be in possession of the user at the time of application.
We have also isolated C. gloeosporioides associated with some of the plants in problem fields. In cases where such plants have been diagnosed, growers should consider the following fungicide program: Apply Quadris alone, then a Captan/Benlate OR Captan/Topsin-M tank mixture five to seven days later. Continue this alternating fungicide program but do not use Quadris for more than the allowed amount according to the label. Follow all fungicide labels carefully and do not use Benlate in pick-your-own fields.
In cases where growers do not have diagnosed problems with stunted and dying plants, C. gloeosporioides is likely not a factor to consider. In such cases, the Benlate or Topsin-M are not needed except at early bloom and again at "full" bloom for Botrytis fruit rot control and according to standard recommendations. Quadris does not cure infected plants nor is it completely effective at preventing fruit rot. In fungicide trials Quadris has been found to reduce anthracnose fruit rot by about 60% once an epidemic starts. It should function as a helpful tool for growers who adopt an IPM program. Therefore, growers need to alternate Quadris with Captan and remove infected fruit from the field when practical to limit the build-up of spores. Success has also been achieved by immediate removal of infected plants and surrounding plants if anthracnose starts in a "hot spot" in the field.
Quadris should not be used indiscriminately. Most growers in North Carolina have no or low risk of anthracnose and Quadris is not needed in such cases. Quadris has a specific mode of action of action and improper use will make the fungicide ineffective for the control of anthracnose if the problem pathogens acquire resistance. Resistance management is an essential component of using Quadris.
For more information, contact your local North Carolina Cooperative Extension Service office or Dr. Frank Louws at 919-515-6689.
QUADRIS® Flowable
EPA Reg. No. 10182-415
Effective Date:
April 11, 1999
A Fungicide For Control Of Anthracnose on Strawberries
DIRECTIONS FOR USE
It is a violation of Federal law to use this product in a manner inconsistent with its labeling.
FAILURE TO FOLLOW THE USE DIRECTIONS AND PRECAUTIONS ON THIS LABEL MAY RESULT IN PLANT INJURY OR POOR DISEASE CONTROL.
INTEGRATED PEST (DISEASE) MANAGEMENT: QUADRIS Flowable should be integrated into an overall disease management strategy for each field. Cultural and agronomic practices known to reduce disease development should be followed. These include adapted least susceptible variety, optimum plant population, proper fertilization, crop rotations and water management practices. Consult your local agricultural authorities for additional IPM strategies established for your area.
STRAWBERRY APPLICATION DIRECTIONS
QUADRIS Flowable should be applied prior to or in the early stages of disease development. Applications may be made by ground only. Use sufficient water volume for adequate coverage (a minimum of 20 gallons of water is recommended).
|
Crop |
Target Diseases |
Use Rate fl. Oz product/A (lb al/A) |
Remarks |
|
Strawberries |
Anthracnose (Colletotrichum acutatum) |
6.2 - 12.4 fl. Oz (0.10 - 0.20) |
Apply QUADRIS at 7 to 14 day intervals at 6.2 to 12.4 fl. oz./A. Applications can be made up to day of harvest. Use the higher rate when conditions for disease epidemics are severe. No more than 3 sequential applications of Quadris should be made before alternating with fungicides that have a different mode of action. Do not alternate or tank mix with fungicides to which resistance has developed in the pathogen population.Do not apply more than 4.6 pints of product per acre per crop (1.2 lbs ai/A). |
The treated area cannot be rotated to broadleaf and root crops for 30 days after application. There is a re-entry interval of 4 hours after application. Quadris should not be applied when conditions favor spray drift.
QUADRIS Flowable Rate Conversion Chart
|
Fluid Ounces Product/A |
Lb ai/A |
Treated Acres/Gal Product |
|
6.2 |
0.10 |
21.3 |
|
7 |
0.11 |
18.3 |
|
8 |
0.13 |
16.0 |
|
9 |
0.15 |
14.2 |
|
10 |
0.16 |
12.8 |
|
11 |
0.18 |
11.6 |
|
12 |
0.20 |
10.7 |
|
13 |
0.21 |
9.8 |
All applicable directions, restrictions and precautions on the container label are to be followed.
This labeling must be in the possession of the user at the time of application.
QUADRIS® is a trademark of a ZENECA Group Company
RS-990409