Teaching to Achieve Sustainable Management of Phytophthora Diseases on Horticultural Crops

Final Report for ENE96-017

Project Type: Professional Development Program
Funds awarded in 1996: $46,500.00
Projected End Date: 12/31/2000
Matching Non-Federal Funds: $31,336.00
Region: Northeast
State: New Jersey
Project Leader:
Jack Rabin
Rutgers Cooperative Extension
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Project Information


• Ag professionals using training and educational materials developed can assist farmers to implement ecological approaches management of costly losses from Phytophthora diseases through soil and water modifications.

• Through the training materials developed, misdiagnoses and inappropriate fungicide applications is reduced.

• Fifty field professionals were trained to recognize symptoms, understand treatments and utilize ecological controls when advising growers.

• The project developed crop specific management fact sheets for growers.

Project Objectives:

1. Document crop specific cultural practices known to reduce incidence and severity of Phytophthora diseases and prepare guidelines.

2. Implement field education stressing adoption of cultural practices in high-value horticultural crops to reduce Phytophthora.

3. Train participants and users of distributed materials to properly diagnose field problems and make more judicious use of fungicides.


Phytophthora diseases have become damaging to a broad array of high value horticultural crops in the mid-Atlantic region leading to millions of dollars of crop loses annually. In many cases Phytophthora disease has become a more limiting factor than market prices or market access for sustaining profitability of high-value crops. In addition to the crop losses, many crops are fungicide treated by farmers who fear devastating crop losses. These applications are costly and many times only marginally effective. This grant sought to define a different approach, concentrating on implementing well defined soil and water practices first, before fungicides to reduce losses to Phytophthora diseases.

Educational Approach

Educational approach:


• A workshop was held September 28 29, 1998 entitled "Soil and Water Practices to Manage Phytophthora in the Mid Atlantic Region," with program and attendance list (attached), which included USDA, private crop consultants, county agents, specialists, graduate students from 3 4 states and utilized growers who implemented practices as teachers.

• A feature article in a professional journal was published (Plant Disease 83(12): 1080 1089 entitled "Ecologically Based Approaches to Management of Phytophthora Blight on Bell Pepper."

• A workshop entitled "Managing Phytophthora Diseases in Vegetable Crops" was held at the Annual NJ Vegetable Growers Meeting, January 1999. Estimated attendance was 200+ and included growers, researchers, and field professionals. Because of open attendance without registration, no lists could be prepared and submitted.

• Training materials and training provided to county agents has resulted in numerous grower education programs in the region including materials developed in the grant. One example is the "Mid Atlantic Pumpkin School," March, 1999.

• A hyper linked document containing educational materials developed during the grant period will be freely distributed on CD and via the internet.

No milestones

Performance Target Outcomes

Activities for farmers conducted by service providers:

Project Outcomes

As a result of this grant, in our local region we have reversed the order of production recommendations on affected crops. For example, fungicide applications are not recommended until soil, crop, and water management strategies are implemented. In several situations fungicide applications have been reduced or eliminated.

A list of affected crops in the region includes: Tree fruit (apple, peach); small fruit (blueberry, cranberry, raspberry, strawberry); Solanaceous crops (eggplant, pepper, potato, tomato); all Cucurbit vine crops (cucumber, summer/winter squash, pumpkin); and Ericaceous ornamentals (azalea, rhododendron, pieris, leucothoe).

Three disease management Fact Sheet checklists for use by ag professionals and farmers in their fields were developed for distribution on the crops Bell Pepper, Pumpkin and Cranberry.

A packaged set of educational training materials, all obtained from validated field research, for both general and specific applications were prepared as a series of hyper linked documents distributed on CD. This set includes:
-Basic biology, life cycles, spore dispersal
-Methods for isolation from infected host tissues
-Testing fungicide sensitivity
-Scenarios for specific crops
-Mulching practices for disease management
-Specific recommendations for crops:

1. Fact Sheet
2. Plant Disease Feature Article
3. Slide Show

1. Fact Sheet
2. Slide Show

1. Fact sheet
2. Results of a Farmer/Grower SARE grant
3. Detailed handout
4. Slide show on CD in MS PowerPoint format with speakers notes that ag professionals can view on computer screen for their own training or project for presentation to farmers with accompanying speakers notes.

Comments from practical growers: Presented as a 18
question and answer 4-page interview with a farmer who has implemented recommended soil and water and rotational practices on his own farm to reduce Phytophthora.

Potential Contributions

• Federal cost share (EQUIP) program (NRCS NJ) recognizes ecological management of Phytophthora. as eligible for funding.

• The threat of Phytophthora can cause growers to choose lower value resistant crops instead of the high risk more valuable ones. By following recommended soil and water management practices the higher value crops can be successfully cultivated in high risk areas.

• Losses from chronic infection in perennial crops such as cranberry can result in 60% crop reductions per year. Deep homogenization offers a non chemical approach for reducing these losses.

Training adoption and direct impact

• Improved ability of field consultants to recognize Phytophthora symptoms has resulted in accurate diagnoses and to make relevant recommendations

• In our local region we have reversed the order of production recommendations on affected crops. For example, fungicide applications are not recommended until soil, crop, and water management strategies are implemented. In several situations fungicide applications have been reduced or eliminated.

Feedback from farmers

See interview with Bob Muth. Also, Frank Sorbello and Abbott Lee underscored the importance of training to help growers implement ecological methods for Phytophthora management.

Future Recommendations

Targeting one specific organism (Phytophthora) was unusual for a USDA-SARE PDP grant. The benefits included developing a multicrop approach to developing guidelines and finding general crop management recommendations.

This training project could not have been implemented without drawing on years of Land Grant and Extension applied research to firmly validated recommending the cultural practices instead of chemical controls.

The identification of chronic infection as an important component of crop loss in cranberry was, in part, discovered through research conducted under this grant. Future research could target improved detection methods.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.