April 8, 2000
BunchGrapes Information


Weather Forecast Information

Here is some weather forecast information you might find useful.

20 hour forecasts updated every 3 hours (temperature, dewpoint, windspeed, etc.):
http://tgsv5.nws.noaa.gov/tdl/lamp/bullform.html

2 day forecasts updated twice daily (temperature, dewpoint, windspeed, etc.):
http://tgsv5.nws.noaa.gov/tdl/forecast/ngm/bullform.htm

weekly forecasts updated twice daily (min/max temperature, windspeed):
http://tgsv5.nws.noaa.gov/tdl/forecast/mrf/bullform.htm



PROJ - Projection in hours.

UTC - The Coordinated Universal Time. We are 4 hours behind UTC in the EST time zone. 00 UTC = 8pm Eastern Daylight Savings Time

TEMP -Temperature in Fahrenheit.

DEWPT - Dewpoint in Fahrenheit.

POPO - Probability of precipitation occurring on the hour. The precipitation need not be measurable.

PRECIP - Whether or not precipitation is expected. A "P" indicates that precipitation is expected on the hour.

POP06 - Probability of measurable precipitation in a 6-hr period.

PTYPE - Precipitation type. One of five types: pure freezing, frozen, liquid, a mix of rain and snow, or a mix of snow and freezing.

POZR - Probability of freezing rain.

POSN - Probability of snow.

OBVIS - Obstruction to vision. One of five types: none, haze, smoke, blowing phenomena, or fog.

VIS CAT - Visibility category.

HTc - Cloud heights in hundreds of feet where "c" is the layer reported. The variable "c" can be of the value 1 through 3.

CVRc - Cloud cover where "c" is the layer reported. The variable "c" can be of the value 1 through 3.

WNDDIR - Wind direction in tens of degrees.

WNDSPD - Wind speed in knots. (knots to mph factor = 1.15 (mph) / (knots)

Eric Bish
Extension Associate / Small Fruit & Viticulture
North Carolina State University
256 Kilgore Hall / Campus Box 7609
Raleigh, NC 27695-7609
919-515-3705 (office&mobile)
919-515-2505 (fax)
eric_bish@ncsu.edu


Disease Control Update

This is an update to the disease advisory posted at:
http://www.agr.state.nc.us/markets/commodit/horticul/grape/discont.htm
Please check this site for disease information and identification.

Always read the label for restrictions and other information.

Several people have asked for an outline of what diseases are important at different times throughout the season.
Pleae note that I am not a Plant Pathologist. This information is taken from talks at several meetings I attended. Any comments would be welcome.

Bud Break Early Shoot Growth

n Phomopsis - important for cane and rachis infections
- Mancozeb,captan
n Powdery Mildew (PM) - moderate risk - wait for forecasted rain?
- Sulfur (variety/temperature restrictions)
n Black Rot (BR) - slight/moderate risk if present last year
- Mancozeb
n Downy Mildew (DM) - no
n Botrytis - no



10" Shoot Growth (2wk Pre-bloom)

n PM - Important to prevent infection
- Sulfur (variety/temperature), SI, Abound?
n BR - can be important if wet and carryover
- Mancozeb, Nova/Bayleton(SI)
n DM - Inoculum mature, important if wet/carryover
- Mancozeb,captan (Abound?)
n Phomopsis - important for cane and rachis infections
- Mancozeb,captan
n Botrytis - no ?


Immediate Pre-bloom

n PM - Critical
- Abound, SI, Sulfur ? (variety/temperature)
n BR - Critical
- Abound, Nova/Bayleton(SI), Mancozeb
n DM - Critical
- Abound, Mancozeb,captan
n Phomopsis - Rachis/berry infection if high pressure
- Mancozeb,captan, (Abound?)
n Botrytis - almost ?


Bloom

n PM, BR, DM - Critical, Phomopsis
- Same as prebloom
- This spray should still be effective (2nd)
n Botrytis - Important if wet and a susceptible variety
- Vangaurd, Elevate, Abound(?)

First Post-bloom (Pre-bloom +10-14 days)

n PM - Critical
- Abound, SI ? , Sulfur ? (variety/temperature)
n BR - Critical
- Abound, Nova/Bayleton(SI), Mancozeb
n DM - Critical
- Abound, Mancozeb,captan
n Phomopsis - Rachis/berry infection if high pressure
- Mancozeb,captan, (Abound?)
n Botrytis - Important if wet and a susceptible variety
- Elevate, Abound(?)

Second Post-bloom (1stPost-bloom+7 ? 14 days)
n PM - Important
- Abound, SI ? , Sulfur ? (variety/temperature)
n BR - Important
- Abound, Nova/Bayleton(SI), Mancozeb (66 d PHI), Ziram (?)
n DM - Important if established and wet
- Abound, Mancozeb (PHI?),captan, Ridomil?, Copper?
n Phomopsis - Rachis/berry infection if high pressure
- Mancozeb,captan, (Abound?)
n Botrytis - Important if wet and a susceptible variety
- Vangaurd, Elevate, Abound(?)

Mid-Summer Sprays
n PM - Important to keep maintained
- Sulfur ? (variety/temperature), Abound?, SI ? ,
n DM - Can be important if established and wet
- Captan, Copper, Ridomil?, Abound?
n BR - Fruit should be resistant unless high pressure
n Phomopsis - No
n Botrytis ? No

Verasion
n PM - Important to maintain clean foliage
- Sulfur ? (variety/temperature), Abound?
n Botrytis - Can be important if wet and susceptible variety
- Vangaurd, Elevate
n DM - Can be important if established and wet
- Captan, Copper, Ridomil?, Abound?
n BR - No
n Phomopsis ? No

After Harvest
n PM - Important to slow infections next year
- Sulfur ? (variety/temperature)
n DM -?
n BR - ?
n Phomopsis - ?
n Botrytis ? No

First Year Disease Management
- Disease control is easiest the first year because fruit should not be present. BUT DON"T BE SLACK! Disease pressure will build up and be a BIG problem the next season.
- Foliar diseases - powdery and downy mildew
o Approx. 6 sprays beginning at 12" shoot growth.
o SI fungicide (e.g. nova) plus mancozeb - first two sprays (April and May)
o Sulfur and mancozeb can be applied for the third spray if variety used is tolerant and it is between 65-90 F (June)
o SI fungicide (e.g. nova) plus mancozeb - fourth and fifth sprays (July and Aug)
o Sulfur and mancozeb can be applied for the final spray (see note above)


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Eric Bish
Extension Associate / Small Fruit & Viticulture
North Carolina State University
256 Kilgore Hall / Campus Box 7609
Raleigh, NC 27695-7609
919-515-3705 (office&mobile)
919-515-2505 (fax)
eric_bish@ncsu.edu

Contributed by:

Eric Bish, Extension Associate
Horticultural Science
256 Kilgore Hall, Box 7609
Raleigh, NC-27695
919.515.3705 (Phone)
919.515.2505 (Fax)
eric_bisch@ncsu.edu

The Southern Region Small Fruit Consortium
Box 7601
North Carolina State University
Raleigh, North Carolina 27695-7601
919-515-6963

Please direct comments or suggestions to
Brenda J Willis
706-542-2471