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On August 01, 2018

To Watch For Downy Mildew In Vine Crops

 

With the recent period of heavy rain, the threat of diseases on various crops has increased significantly. Extension Horticulture Educator Tim Elkner shares these thoughts on our current situation and what steps growers should be taking at this time.

 

Downy mildew has not been found in southeast Pennsylvania yet but has been reported in central Pennsylvania, Maryland and New Jersey on cucumbers and in Delaware on both cucumbers and cantaloupe. This disease can spread rapidly under ideal weather conditions and if not controlled can destroy a crop in a short period of time. Downy mildew is also difficult to remove from a field once it starts; at best a grower will only be able to slow the spread of the disease.

 

Cucumber growers should have been including fungicides in their disease management programs to control downy mildew already since it has been found nearby. It is suggested that growers of the other vine crops such as cantaloupe, butternut squash and pumpkins include downy mildew fungicides in their programs now as well. Our recent spell of wet weather provided perfect conditions for this disease to start in the area. In addition, the weather pattern of south to north air movement was ideal for transporting the spores from downy mildew infected fields in the southern part of the US into our area. Downy mildew was found in all vine crops in a sentinel plot in eastern North Carolina and there is a reasonable chance that spores could have been carried to our area from that region during the recent rainy period. 

 

A good fungicide program will include a protectant material (such as chlorothalonil) in addition to the materials specific for controlling downy mildew. Growers should consult their copy of the 2018 Mid-Atlantic Commercial Vegetable Production Recommendations for a listing of fungicides to be used for controlling this disease. It is important to rotate FRAC codes when applying fungicides to vine crops and to follow all label recommendations and restrictions, particularly the days to harvest limitations since we are now in the harvest season for several of our vine crops. For growers with access to the internet, the 2018 FRAC Table for Cucurbit Downy and Powdery Mildew Control in the mid-Atlantic Region can be found and downloaded at: www.plantmanagementnetwork.org/pub/php/volume19/number1/PHP-12-17-0077-BR.pdf. 

 

Copies of this table have also been placed at some of the local produce auctions. Growers should promptly destroy fields which are no longer being harvested or sprayed in order to help control the spread of downy mildew as well as other diseases and insects in vine crops.

 

To Monitor Corn and Soybeans For Diseases

 

While corn and soybean crops tend to be less susceptible to diseases than many produce crops, the recent heavy rains created a situation where these crops can also be infected with disease. Extension Plant Pathologists Alyssa Collins, Paul Esker and Adriana Murillo-Williams share these thoughts on foliar diseases on corn and soybeans.

 

They suggest once things dry up, producers should start scouting with an eye toward leaf lesions, especially on the lower canopy.  Fungi survive in our residue from previous crops, so many diseases will appear first on the lower parts of plants where rain has splashed the spores up.  Try to get a sense of how much of the field is affected by a given disease.

 

If you sprayed before the rainy period should you spray again. In short, no.  Most of the fungicide products that are popular for our field crops move into plant tissue very quickly, and won’t wash off.  This is one of the reasons they last for two to three weeks.

 

If you have not sprayed and if your beans are younger than R3, or your corn is pre-tassel and more rain/humidity is likely, a spray may be warranted.  Check out this article for details https://extension.psu.edu/let-s-talk-diseases-in-corn-and-beans.

 

The most recent storm system brought air up from the south.  That air may have also brought spores with it.  Don’t be surprised if we soon begin to see diseases that are more common later in the season, or are caused by pathogens that don’t overwinter in PA, like southern rust of corn.  Soybean rust probably won’t make it all the way here in one storm, but this will help it move north of its current location in Florida and Louisiana.

To Participate In The Equine Experience At Ag Progress Days 

 

Ag Progress Days is a great place for horse lovers of all ages. During the three-day event, August 14-16, visitors can attend breed demonstrations, clinics and much more reports Kelly Jedrzejewski in Penn States Animal Science Department.

“People really enjoy the variety of activities and horses we offer at the Equine Experience,” said Brian Egan, instructor in equine science in Penn State’s College of Agricultural Sciences. “From miniature horses to draft horses, the horse arena is always a popular destination at Ag Progress Days, and we’re looking forward to another successful year.”

Education is a pivotal part of the schedule, Egan noted, and this year is no exception. Several clinics on horsemanship skills and handling and training of young horses will take place at the Equine Arena, located at the top of Main Street at the Ag Progress Days site.

In addition, Penn State Equine Science faculty and staff and members of the Pennsylvania Equine Council will be available in the Equine Exhibits Building throughout the three days to answer questions and provide information on equine-related topics.

New this year, horse owners can join Penn State Extension’s equine team at 11 a.m. and 2 p.m. daily to learn about fecal egg counts. These tests are important to monitor a horse’s parasite load and can help owners plan an appropriate deworming schedule, Egan said. Visitors can bring a sample of their horse’s manure to be tested at no charge. Samples must be fresh (less than 12 hours old) and kept cold (refrigerate at home; bring in a cooler to test).

Quote Of The Week: “Rain is grace; rain is the sky condescending to the earth; without rain there would be no life.” John Updike