Cornell Vegetable Program Enrollment

Program Areas

  • Food Safety
  • Variety Evaluation
  • Market Development
  • Pest Management
  • Cultural Practices

Enrollment Benefits

  • Telephone / Email Consultations
  • VegEdge Newsletter
  • Direct Mailings
  • Educational Meetings & Conferences
  • In-Field Educational Opportunities
  • On-Farm Research Trials

CVP Enrollment Form (PDF; 147KB)

Enrollee Login

Password:

Log In To Access:

  • Issues of VegEdge Newsletters
  • Helpful Diagnostic Tool:
      What's wrong with my crop?

Not an Enrollee? Enroll Now!

Online Enrollment Form

Determining Late Blight Sensitivity to Ridomil Takes Time

Carol MacNeil, Extension Vegetable Specialist
Cornell Vegetable Program

September 19, 2013

Determining Late Blight Sensitivity to Ridomil Takes Time
Late blight (LB) is present everywhere now, affecting most counties in WNY, Central NY, Southeastern NY, and the St. Lawrence Valley, in addition to all adjacent states and provinces. Destroy any LB hot spots, foliage in fields where LB is out of control, and abandoned plantings ASAP to reduce the population of spores present to infect late plantings! Continue fungicide sprays until all vines are dead and dry. If LB is present on your farm do not stretch your sprays beyond the shortest interval on the fungicide label for LB on your crop.

Aside from one sample each of US-8 in Erie, PA, and WI, a new strain in OH, and one sample of US-24 in ME, all samples submitted have been identified as US-23. Three LB samples were collected 9/2 from two nearby farms in Wayne Co. where two applications of Ridomil did not appear to control LB. A dozen samples collected from the same area 9/9, where LB had continued to increase, were all identified as US-23. While US-8 is resistant to mefenoxam (Ridomil, OLF), and US-24 has variable resistance, US-23, to date, has always been sensitive to mefenoxam. A preliminary test of mefenoxam sensitivity done a few days ago on the 3 original LB samples from the problem fields in Wayne Co. showed US-23 to be sensitive to mefenoxam, but a more definitive test is being done. Pure cultures of those LB samples are needed so the test will take a few weeks.

The % LB diseased foliage in a field significantly affects how well any fungicide works against it. From Bill Fry, Cornell, 9/16/13: "Years ago we did experiments on the effect of timing of Ridomil on the suppression of LB [on a sensitive LB strain]. The treatments included metalaxyl/Ridomil, mancozeb, or no fungicide. We initiated applications at ~0.5% disease or at 2-5% diseased [foliage]. The effects of Ridomil were apparent within a day or two, but the effects of mancozeb were not visible for at least one week. LB increased explosively in the mancozeb and untreated plots for the first week. Subsequently, mancozeb did slightly suppress disease relative to the water control. The effect of Ridomil was dramatically different with an immediate observable effect in [reducing disease development].  Nonetheless, the amount of disease in the Ridomil plots continued to increase gradually for the next four weeks. When we initiated Ridomil applications at 0.5% disease the final level of disease was less, and the rate at which disease increased was less, than when we began at 2-5% diseased foliage. There was inoculum from other plots that probably contributed to increased LB. Thus, once disease is established, it's really difficult to totally stop this pathogen. I suspect that given the wet weather and favorable conditions we've had recently, any fungicide may have been challenged."  

If mefenoxam (Ridomil, OLF) is not working on your farm rotate to a LB fungicide such as Previcur Flex plus protectant, Ranman plus, Revus Top or Forum plus. If you're close to potato vine-kill use a fungicide good against tuber blight such as Gavel, Zoxium plus protectant, Ranman plus, or Forum plus. (Info from T. Zitter, 7/12/13) 

If you think Ridomil is not working, or if you have questions regarding LB, contact Carol MacNeil


more crops
Asparagus

Asparagus

Beets

Beets

Broccoli

Broccoli

Brussels Sprouts

Brussels Sprouts

Cabbage

Cabbage

Carrots

Carrots

Cauliflower

Cauliflower

Cucumbers

Cucumbers

Dry Beans

Dry Beans

Eggplant

Eggplant

Ethnic Vegetables

Ethnic Vegetables

Garlic

Garlic

Horseradish

Horseradish

Kohlrabi

Kohlrabi

Leeks

Leeks

Lettuce / Leafy Greens

Lettuce / Leafy Greens

Melons

Melons

Onions

Onions

Parsnips

Parsnips

Peas

Peas

Peppers

Peppers

Potatoes

Potatoes

Pumpkins / Gourds

Pumpkins / Gourds

Radishes

Radishes

Rhubarb

Rhubarb

Rutabaga

Rutabaga

Snap Beans

Snap Beans

Squash - Summer

Squash - Summer

Squash- Winter

Squash- Winter

Sweet Corn

Sweet Corn

Sweet Potatoes

Sweet Potatoes

Tomatoes

Tomatoes

Turnips

Turnips

more crops

Upcoming Events

Muck Donut Hour Every Tuesday

July 16, 2019
8:30 - 9:30 AM
Elba, NY

Meet with Cornell Vegetable Program Specialist Christy Hoepting every Tuesday morning to ask questions and share your observations about ONIONS!
view details

Vegetable Pest and Cultural Management Field Meeting for Auction Growers (Yates)

Event Offers DEC Credits

July 19, 2019
Friday, 7:00 - 9:00 PM
Himrod, NY

This course will demonstrate pest management in fresh market vegetables in both field and greenhouse (high tunnel) vegetables, primarily for those growing for wholesale auction. A hands-on demonstration of weed, insect and disease identification in vegetables including management options such as inter-row cover crops, grafting, and where appropriate, spray options will be used to educate growers. Judson Reid, Senior Extension Associate with the CCE Cornell Vegetable Program along with CCE staff will instruct participants and facilitate peer-based learning. Details on each topic will focus on field observations at these farms. 
view details

Muck Donut Hour Every Tuesday

July 23, 2019
8:30 - 9:30 AM
Elba, NY

Meet with Cornell Vegetable Program Specialist Christy Hoepting every Tuesday morning to ask questions and share your observations. Grower experience is combined with research and scouting information for a whole lot of talk about growing ONIONS! All are welcome to join us!
view details

Announcements

NY Crop Insurance Availability by County & Crops

Apiculture, Dairy-RP, LGM, Nursery, PRF and WFRP policies are available throughout the entire state. A table has been developed showing RMA crop insurance availability by county and crop in New York State.

If a crop is not covered in your county, you may still be eligible for a written agreement for that crop. Please contact an insurance agent to see if this is an option for you.

More information about crop insurance is available through Cornell's New York Crop Insurance Education Program.

Cornell Commercial Vegetable Guidelines Available

The 2019 Cornell Integrated Crop and Pest Management Guidelines for Commercial Vegetable Production are now available!

Written by Cornell University specialists, this publication is designed to offer producers, seed and chemical dealers, and crop consultants practical information on growing and managing vegetable crops in New York State. Topics include general culture, nutrient management, transplant production, postharvest handling, organic production, and managing common vegetable crop pest concerns. A preview of the Vegetable Guidelines can be seen online.

Highlighted changes in the 2019 Vegetable Guidelines include:
  • Updated pesticide options for economically important vegetable crop pests.
  • New pests: beet armyworm in beets; cabbage looper and tarnished plant bug in lettuce and endive; allium leafminer in onions; and Cladosporium, Cercospora, and Stemphylium leaf spots in spinach.
Cornell Crop and Pest Management Guidelines are available as a print copy ($41), online-only access ($41), or a package combining print and online access ($57.50). Shipping charges will be added to your order. Cornell Guidelines can be obtained through many local Cornell Cooperative Extension offices, or from The Cornell Store at Cornell University or call (844) 688-7620.

NEWSLETTER  |  CURRENT PROJECTS  |  IMPACT IN NY  |  SPONSORSHIP  |  RESOURCES  |  SITE MAP