Timing Fungicides for Pumpkins

1. Timing Fungicides for Pumpkins Powdery Mildew Control Fungicide applications for control of pumpkin diseases in Ohio are generally started when Powdery Mildew appears the last week of July or first week of August.Fungicide applications for control of pumpkin diseases in Ohio are generally started when Powdery Mildew appears the last week of July or first week of August.

2. �Mildewcides� Quadris Flint Topsin M Nova Microthiol Disperss Benlate Specialty fungicides which control Powdery Mildew (such as Benlate, Topsin M and Nova) must be added to some wide spectrum fungicides to adequately control this disease. Flint and Quadris are broad spectrum fungicides which will control Powdery Mildew. Microthiol Disperss is a sulfur compound that can control Powdery Mildew in some organic programs. Specialty fungicides which control Powdery Mildew (such as Benlate, Topsin M and Nova) must be added to some wide spectrum fungicides to adequately control this disease. Flint and Quadris are broad spectrum fungicides which will control Powdery Mildew. Microthiol Disperss is a sulfur compound that can control Powdery Mildew in some organic programs.

3. PROBLEMS Quadris/Flint must alternate with Chlorothalonil or Mancozeb Chlorothalonil and Mancozeb are not good mildewcides Bravo and Echo are fungicides containing chlorothalonil. Maneb and Dithane are examples of fungicides containing mancozeb. Quadris and Flint are strobiluron fungicides. Alternative programs are necessary to avoid development of races of fungi resistant to these materials. Bravo and Echo are fungicides containing chlorothalonil. Maneb and Dithane are examples of fungicides containing mancozeb. Quadris and Flint are strobiluron fungicides. Alternative programs are necessary to avoid development of races of fungi resistant to these materials.

4. SO Benlate or Nova or Topsin M are added to alternating sprays of Mancozeb or Chlorothalonil for Powdery Mildew Control

5. BUT Benlate is no longer manufactured (supplies should be adequate for growing season 2002) Note : Topsin M is a similar chemistry

6. Powdery Mildew Program Begin sprays last week of July in Ohio

7. Powdery Mildew Program Spray #1 = Quadris/Flint Spray #2 = Chlorothalonil or Mancozeb + Nova Spray #3 = #1 Spray #4 = Chlorothalonil or Mancozeb + Benlate or Topsin M A fungicide program such as that outlined above will adequately control Powdery Mildew and many other fungal leaf and fruit diseases of pumpkin. When using a multi-spray program, keep careful records to avoid exceeding season use total for the fungicides in the program.A fungicide program such as that outlined above will adequately control Powdery Mildew and many other fungal leaf and fruit diseases of pumpkin. When using a multi-spray program, keep careful records to avoid exceeding season use total for the fungicides in the program.

8. Powdery Mildew Program If more sprays are needed repeat schedule Continue program to protect handles Remember number of applications are determined also by total usage limits on label

9. Further Considerations Genetic resistance for Powdery Mildew permits control with fewer sprays and less specific fungicides.(Merlin/Magic Lantern) Veg. Prod. Guide *PMT

10. Further Considerations Powdery Mildew program as outlined will control most foliar and fruit diseases If Anthracnose is a problem in wet springs, start program in mid-June without addition of Mildewcides

11. Further Considerations If Microdochium Blight is a problem start program in June with Mancozeb fungicides without mildewcides For Microdochium Blight control our preliminary tests indicate that mancozeb fungicides, Flint and Quadris provide efficient control. Chlorothalonil fungicides do not.For Microdochium Blight control our preliminary tests indicate that mancozeb fungicides, Flint and Quadris provide efficient control. Chlorothalonil fungicides do not.

12. Further Considerations Begin outlined Powdery Mildew Program in all cases the last week of July

13. Cultural Management Clean Seed Crop Rotation Corn, Grass Crops/ Good Vine Crops, Tomato, Pepper, Soybean/Bad No program for disease control in pumpkin should depend solely on fungicides. Unless an integrated approach to disease control is in place, fungicide efficacy will decline. Good control of diseases depends on using clean seed in clean soil. It is best to avoid planting pumpkin in soil which has produced vine crops within 3 years. Do not follow tomato, pepper or soybean with pumpkins.No program for disease control in pumpkin should depend solely on fungicides. Unless an integrated approach to disease control is in place, fungicide efficacy will decline. Good control of diseases depends on using clean seed in clean soil. It is best to avoid planting pumpkin in soil which has produced vine crops within 3 years. Do not follow tomato, pepper or soybean with pumpkins.

14. Cultural Management Good Internal and Surface Soil Drainage Cover Crops Insect Control Good horticultural practices need to be followed to maximize the efficiency of disease control programs. Insect control is vital to the success of disease control programs. Insects can vector important bacterial and viral diseases. They can cause wounds which favor development of some fungal and bacterial diseases.Good horticultural practices need to be followed to maximize the efficiency of disease control programs. Insect control is vital to the success of disease control programs. Insects can vector important bacterial and viral diseases. They can cause wounds which favor development of some fungal and bacterial diseases.