Several pumpkin growers have asked me when to stop managing for pumpkin diseases. That is, when should a pumpkin grower stop applying fungicides? I cannot provide a definitive answer for this question; every grower will have to make his or her own decision. Below, however, are some factors to consider. Estimate the crop yield-walk through the field and…Read more about Late Season Pumpkin Disease Management[Read More]
Cucurbits
Many of us may forget about the pesky squash vine borer until it’s too late. This pest of cucurbit crops tends to be sporadic in our region; you are either battling it every year or it hardly makes an appearance. The squash vine borer is a member of the clear-winged moths, a unique group of…Read more about What’s Eating my Squash?[Read More]
Before writing this article, I went back to an old article from 2015. In 2015, I had written, Plectosporium blight was more severe than normal. In 2018, I have also observed more Plectosporium blight than usual. It is not clear to me why this disease seems to be more widespread compared to recent seasons. However,…Read more about Plectosporium Blight of Pumpkins[Read More]
Hollowheart of watermelons is a physiological fruit disorder. Flesh separates inside of the fruit, typically forming three gaps (Figure 1 and 2). In severe cases, hollowheart could cause watermelon load rejection. Watermelon fruit that has hollowheart tends to be triangular shaped. Poor pollination is the primary reason causing hollowheart. Scientists were able to prove that seedless watermelons…Read more about Hollowheart of Watermelons[Read More]
Cucurbit downy mildew has been observed on cucumber in LaPorte County and LaGrange Counties, in northern Indiana and Knox County in the southwest. Downy mildew of cucurbits has also been reported in Kentucky and Michigan. See this article (https://vegcropshotline.org//article/cucurbit-downy-mildew/) in the last Hotline issue about details of downy mildew. Whether growers manage for downy mildew…Read more about Downy Mildew Update[Read More]
Cucurbit downy mildew has been observed on cucumber in La Porte County and LaGrange Counties, Indiana. Downy mildew of cucurbits has also been reported in southern and central Kentucky. All cucurbit growers in Indiana should be scouting and managing for downy mildew. The organism that causes downy mildew of cucurbits doesn’t overwinter in Indiana. It has…Read more about Cucurbit Downy Mildew[Read More]
Watermelon harvest is in full swing in southern Indiana. At this time, we frequently see many types of leaf symptoms. Some of them are caused by foliar diseases, such as anthracnose, Alternaria leaf blight and gummy stem blight. These diseases require special attention, normally in the form of fungicide sprays, to slow spread of the…Read more about Not All the Watermelon and Cantaloupe Leaf Symptoms are caused by Pests[Read More]
Powdery mildew is a common disease of cucurbits in Indiana. This disease is more common on cantaloupe and pumpkin. However, we have observed powdery mildew more frequently on watermelon in recent years. We have also observed this disease on cucumber in high tunnels. If left uncontrolled, this disease can cause loss of foliage, loss of…Read more about Powdery Mildew of Cucurbits[Read More]
Despite the wet start to the summer that we are experiencing, we have some growers reporting spider mites in field watermelons (Figure 1). This pest is typically associated with hot, dry weather and can be especially problematic in crops grown under protection, such as in high tunnels. Spider mites often move into a field from…Read more about Spider Mites on Cucurbit Crops[Read More]
Bacterial wilt is one of the most destructive diseases in high tunnel cucumber production. The reason bacterial wilt is so important is because, like other wilt diseases, it ties up with the entire vascular system of a plant, causing systemic effects (Figure 1). The relatively less important roles that other cucumber diseases play also make…Read more about Bacterial Wilt of Cucumbers Grown in a High Tunnel[Read More]