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On July 08, 2017

Given the mild winter and earliness of berry crops this year, it’s not a big surprise that spotted wing drosophila presence is early, too.

Extension Horticulture Educator Kathy Demchak reports we caught one female in one of our 18 traps the week of June 19, and one female in each in three traps out of 18 the week of June 26. That means that it’s time for growers to be spraying with effective labeled insecticides, weekly if not more frequently, to protect susceptible berry crops from spotted wing drosophila (SWD).

Cultural methods of management that reduce numbers include:
using exclusion netting if in tunnels, maintaining narrow rows to reduce humidity and allow better spray penetration, and harvesting more frequently—with raspberries, every day if possible. An additional step is refrigerating harvested berries as close to 32 degrees as possible.
Growers can monitor with traps, check for larvae in fruit, and watch for juice stains on the receptacles of raspberries during harvest as indications of SWD presence. Or, just assume that SWD is around, because it very likely is.

Thanks to Maria Cramer, our graduate student who is working on SWD management research, for trap deployment and monitoring.

To Monitor For Vegetable Diseases

Extension Plant Pathologist Beth K. Gugino<http://extension.psu.edu/directory/bmk120> encourages producers to be on the lookout for downy mildew on cucumber and cantaloupe. Diseases such as Phytophthora blight, blackleg on potato and bacterial diseases that spread in some of the recent rain events that moved across the Pennsylvania as well as timber rot in high tunnel tomatoes.

Reports of Downy Mildew on Cucumber (and Other Cucurbits) are increasing. Downy mildew was confirmed on cucumber and/or cantaloupe in northeast Ohio (Wayne Co.), Essex, ON (southeastern most tip of Ontario, Canada), southeast Michigan in Monroe Co., and southern New Jersey in Salem Co. Disease pressure is also continuing to build in North and South Carolina on cucumber and cantaloupe with more recent reports now on yellow/summer squash, butternut squash, giant pumpkin and watermelon. With more forecasted unsettled weather, it is important to consider applying at least a protectant fungicide on cucumber and cantaloupe. Since host resistance is not readily available, the timely application of effective fungicides is the primary tool for disease management.

See the 2017 Mid-Atlantic Commercial Vegetable Production Recommendations<http://http/extension.psu.edu/publications/agrs-028/view> for the latest fungicide recommendations for non-certified organic production. For certified organic production, copper-based fungicides remain the primary tool and can be used in combination with products like Serenade, Regalia and Actinovate for suppression.

For the latest information on outbreaks and to receive email or text alerts please visit the Cucurbit Downy Mildew Forecasting website<http://cdm.ipmpipe.org/index.php>:
Updates will also be made to the 1-800-PENN-IPM hotline weekly or more frequently if needed to provide growers with information that can be used to help make timely management decisions. The forecasted risk maps are also based on knowing where there are downy mildew infected fields (sources of the pathogen) so it is important if you suspect downy mildew on your farm to let Gugino know either by email at bkgugino@psu.edu or by phone at 814-865-7328 or contact your local Penn State Cooperative Extension Office.

As expected recent wet weather equals increasing reports of diseases on vegetables. If you live in an area of the state that has been experiencing significant rainfall events, in low lying areas of your fields be on the lookout for symptoms of Phytophthora blight on cucurbit and peppers as well as blackleg or blackleg-like symptoms and late blight on potatoes (and tomatoes). The rain splash is also resulting in a general increase and spread of bacterial diseases across a number of different crops.

The cool and wet conditions this spring were ideal for timber rot to develop in high tunnel tomatoes and as a result we are receiving many questions about what to do next. Timber rot is caused by the same pathogen as white mold or Sclerotinia rot. The pathogen has a very wide host range that includes both cash crops as well as cover crops and weeds which makes crop rotation challenging unless you can rotate to a grain crop for an extended period of time. Therefore, sanitation is a critical component of timber rot management.
As the disease progresses, dark black structures known as sclerotia will develop in the infected tissue and if these structures fall into the soil they can survive up to 10 years or more. It is best to remove and destroy any infected tissue before the sclerotia develop. If sclerotia are visible, it is even more important to carefully remove and bag the plant in the high tunnel. The number and efficacy of fungicides for managing timber rot are limited (primarily Fontelis and Contans, a mycoparasite of the sclerotia) and are best applied when conditions are favorable for disease (prolonged moisture and temperatures <80F).

For more information see Frequently Asked Questions about Timber Rot on Tomato<http://extension.psu.edu/plants/vegetable-fruit/news/2011/frequently-asked-questions-about-timber-rot-on-tomato>

To Attend The Vegetable and Fruit Field Day at Rock Springs

A Field Day for fruit and vegetable growers will be held on July 12, 2017 at Penn State’s Russell E. Larson Agricultural Research Center at Rock Springs, Pennsylvania. Bill Troxell with the PA Vegetable Growers Association reports growers will have the opportunity to see what’s happening with the numerous vegetable and fruit research trials being conducted at the Center.

This event is being sponsored jointly by Penn State University’s College of Agricultural Sciences and the Pennsylvania Vegetable Growers Association. The program will begin at the Horticulture Research Farm located 11 miles west of State College at Gate H on Route 45, just east of the Ag Progress Days site. Projects located on the Horticulture, Plant Pathology, Entomology and Agronomy Research Farms will be discussed.

Registration and refreshments will begin at 8:00 in the morning. At 9:00 there will be a drone demonstration followed by tours of vegetable and small fruit research plots from 9:30 a.m. to 12:30 p.m.. The following projects will be discussed: Weed management in processing tomatoes and sweet corn, Allium leafminer monitoring, Cantaloupe and pepper establishment, Hops, Tomato breeding and Product efficacy trials for vegetable disease management. Other topics to be covered include: Sweet potato size management and butternut squash storage, Low tunnel strawberry production, High tunnel strawberry and raspberry production, Cover crops for vegetable production, Pumpkin variety evaluation, Wine grapes research trials and more.

Lunch consisting of a hearty sandwich accompanied by side dishes, beverage and dessert will be provided. In the afternoon there will be breakout sessions. Track 1will cover Tree Fruit research trials will include Apple rootstock trials, Apple training system trials, Bio-renovation of an orchard site, Weed control in apples, Apple cultivars, Root growth studies, Causal factors of bitter pit in apple, Asian pear cultivars and The Use of DrapeNets for preventing hail damage and to modify canopy growth.
Track 2 on High Tunnels will include Choosing a plastic covering, High tunnel venting and design options, and Berry production in containers. Track 3 will cover Hands-on Vegetable Pest and Disease Identification.
The day will conclude with an optional Sprayer calibration demo qualifying for a pesticide applicator core re-certification credit. The meeting will Adjourn at 4:00 p.m.

The registration fee for the Field Day is $20 for adults ($10 for children 3 to 10, children under 3 are free) if registered by July 10. After July 10, the late registration fee will be $30 for adults ($15 for children). Registration includes lunch, drinks and snacks. Call 717-694-3596 or email pvga@pvga.org<mailto:pvga@pvga.org> to register. Walk-in registrations are welcome.

Quote Of The Week: “May we think of freedom, not as the right to do as we please, but as the opportunity to do what is right.” Peter Marshall