Dan Egel

Clinical Engagement Associate Professor
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While the hard copy of the Midwest Vegetable Production Guide for Commercial Growers 2015 (ID-56) has been available since early January, the on-line version is updated as needed. Below I outline the latest changes. Page 40, Table 16. Several insecticide products were added to the “Insecticide Labeling for Greenhouse Use” table. Page 100, Cucurbit chapter. Luna Privilege® was removed from the lists of suggested products for Alternaria leaf blight control and gummy stem blight/black rot control. While Luna Privilege® is labeled for these uses, it is not available yet. Page 100, Cucurbit chapter. The rates for Presidio® for downy mildew and Phytophthora blight control were modified by the manufacturer. Page 109, Product/Disease Rating for All Cucurbits. Several products were deleted, added, or modified in the Product/Disease Ratings for All Cucurbits table. These include Luna Experience®, Actigard®, Revus® and Presidio®. Page 125, Fruiting Vegetable Chapter. Ridomil Gold SL® was added to[Read More…]

White mold

In early March, I observed white mold of recently transplanted tomato plants in a greenhouse situation. I have described the symptoms, biology and management of white mold at https://ag.purdue.edu/arp/swpap/VeggieDiseasesBlog/Lists/Posts/Post.aspx?ID=18 . I have never observed white mold (a.k.a, timber rot) in February before. I have observed white mold of tomato transplants in April. However, the very small mushroom (smaller than a dime) that is part of the life cycle usually emerges in the spring after a cold period. The appearance of white mold in February may be as a result of the presence of the mushroom in the greenhouse that produced the transplants. To reduce severity of white mold of tomato, I recommend that tomato growers: Inspect transplants for stem lesions which may be a symptom of white mold. Bring questionable symptoms to my attention or send them to the Purdue Plant and Pest Diagnostic Laboratory (http://www.ppdl.purdue.edu/ppdl/index.html). Clean and sanitize greenhouses[Read More…]

Bacterial spot of tomato is one of the most serious diseases facing tomato growers in Indiana. As described at Vegetable Diseases in Greenhouses (PDF), bacterial spot is more of a problem for field tomatoes than for greenhouse tomatoes. Symptoms and management of bacterial spot are described briefly at Bacterial Spot of Tomato and Pepper (PDF). A more detailed version of this article is found at An Update on the Use of Copper Products for Managing Bacterial Spot of Tomato (Blog Post). This article will discuss why copper products have become less useful in the control of this important disease and options for managing bacterial spot of tomato. Copper products have been used for many years to help control bacterial spot of tomato. However, some strains of the bacteria that cause this important disease are resistant to copper—that is, the bacteria have mutated to a form that is no longer sensitive to copper. Some of[Read More…]

Over the last several years, the number of questions I have had about tomato production in high tunnels has increased dramatically. Since I am a plant pathologist, most of the questions I have been asked are about diseases of tomatoes in high tunnels. However, I also have been asked production questions. One particular question about tomato product that may impact disease severity is this: how many staked tomatoes can be grown in a high tunnel effectively? To be honest, the above question is one that I often ask myself when I observe high tunnels in Indiana. It isn’t necessarily one that is asked by growers. But maybe it should be. It has been my observation that growers often try to place too many staked tomatoes in a high tunnel. The result may include diseased tomato plants due to insufficient air circulation, poor quality fruit and even reduced yields. I was[Read More…]

The goal of the Vegetable Crops Hotline is to provide vegetable growers with timely information that helps you to improve your vegetable production and marketing. This url tinyurl.com/lqww2lw links to a very short survey that will help us to make the Hotline more useful to you. We are especially interested in any comments you have regarding how we can improve the dissemination of information. This survey should take you less than 5 minutes to complete so we would be very grateful if you would take the time to complete it. This survey is voluntary and anonymous. All information is confidential and no hidden tracking of individual responses is being used. As always, thank you for your assistance.

Lesions of bacterial fruit blotch on watermelon seedlings are easily confused with angular leaf spot. Check with a diagnostic lab to be sure. (Photo by Dan Egel)

Bacterial fruit blotch is a disease that can affect most cucurbits (see Figure 1). However, the symptoms are most often observed on watermelon. A brief description of this disease and some photos can be found here. This article will introduce new recommendations for this disease in Indiana. Details of these recommendations can be found in the Midwest Vegetable Production Guide for Commercial Growers 2015 (ID-56). Hard copies of the ID-56 are available from Purdue University now for $10. A free on-line version of the ID-56 will be available soon at mwveguide.org. Copper products such as those with copper hydroxide or copper sulfate are often recommended for management of bacterial fruit blotch (BFB).  However copper products applied too often can cause yellowing of leaves and even yield loss (phytotoxicity). Since BFB is mostly caused by rare contaminated seed lots, I have been reluctant to recommend copper products routinely for watermelon growers. However, the last few years I have[Read More…]

While visiting my son in Lincoln, Nebraska this past summer, I had the chance to browse in a second hand store.I felt myself drawn to the book section where I found a green hard cover book titled, “Yearbook of Agriculture, 1928”. From 1894 until 1992, the Department of Agriculture published a Yearbook of Agriculture annually. These books provided updates, features and statistics for the year. The reports actually go all the way back to 1862, when the head of the agriculture department, Isaac Newton, submitted a report to the Commissioner of Patents. (It turns out most of these books have been scanned and are on-line-I could have saved myself $1.50 had I known!) It is my plan to report on parts of the 1928 book that I think might interest vegetable growers in Indiana. The first subject which caught my eye were the statistics for processing tomato production. Below I[Read More…]

​For 100 years bacterial spot has been causing huge losses for tomato ​growers worldwide. For 100 years products containing copper have held the key to controlling this devastating tomato disease. As tomato growers enter their second century of dealing with bacterial spot, the question has become whether copper applications lessen the severity of bacterial spot-or perhaps even make the disease worse. This article will discuss bacterial spot of tomato, why copper products have become less useful in the control of this important disease and finish with options for managing bacterial spot of tomato with and without copper. The first symptoms of bacterial spot one is likely to observe are small, less than 1/8 inch dark lesions on tomato leaves. The lesions may appear watersoaked, especially in the morning and are often surrounded by yellow (chlorotic) tissue. These lesions, whether found on leaves or stems, may coalesce to cause the loss[Read More…]

Bacterial spot of pumpkin often causes scab-like lesions on pumpkins. In this photo

The title of this article is pretty scary. But it isn’t entirely accurate. Pumpkins won’t really rot from the inside out. In this article, I will describe one way in which pumpkins can seem to rot from the inside out. Recently, I was asked to visit a field of pumpkins where the pumpkins were soft and rotting. Some of the pumpkins had already burst. Some were soft and when prodded, the insides flowed out. I set out to try to understand how this could happen. Although it seemed that the rotted pumpkins were healthy on the outside, upon closer examination, I found lesions of bacterial spot on the outside of affected pumpkins. More information about bacterial spot can be found in Vegetable Crops Hotline No. 586. Most lesions of bacterial spot on pumpkin are scab-like on the surface of the pumpkin (see Figure 1). Occasionally, however, such lesions will become[Read More…]

​The Southwest Indiana Melon and Vegetable Growers Association will hold their technical meeting and variety trial showcase on Thursday, November 20, 2014, in the basement of the Southwest Purdue Ag Center, 4369 N. Purdue Road, Vincennes, IN.The meeting will start at 5 p.m. with a general business meeting. At 6 p.m., dinner will be served. Then at approximately 7 p.m.,the variety trial discussion will begin followed by a brief presentation by the Indiana State Department of Agriculture on Food Hubs. Any grower interested in becoming a member is invited to attend. Membership dues are $15 per year and can be paid at the meeting. If you have questions or want to RSVP, please contact Sara Hoke or Dan Egel at (812) 886-0198 or email shoke@purdue.edu. RSVP are due by November 14th.