Tag: Cucurbits
-
Urgent: Powdery Mildew Found on Watermelon in Charleston, SC
From Clemson Plant Pathologist Tony Keinath. Powdery mildew was found on three cultivars of seedless watermelon at the Clemson Coastal REC on May 23, 2023. All watermelon crops in South Carolina should be 1) scouted for powdewry mildew and 2) if found, sprayed to prevent powdery mildew from reducing yields by up to 40%. When…
-
Cucurbit Downy Mildew Found in SC
Prepared by Rob Last, Justin Ballew, and Tony Keinath. Cucurbit downy mildew was identified in South Carolina on 5/12/23. The identification came from butternut squash grown in a sentinel plot at the Coastal REC in Charleston. The same strain that affects butternut squash also affects watermelon and summer squash. Now that downy mildew has been…
-
Question of the Week – Squash Beetle Trenching
This week, the question was: Why is a portion of this squash leaf discolored? The light-colored tissue we see here is the result of squash beetle behavior known as “trenching.” Trenching cuts off (at least temporarily) the translocation of cucurbitacin defense compounds, to preserve the palatability and quality of the squash foliage feeding site. The beetles…
-
Downy Mildew Spreads to Charleston, SC
From Clemson Plant Pathologist Tony Keinath and Extension Agent Zack Snipes. Downy mildew was found on non-sprayed “sentinel” cucumbers at Coastal REC, Charleston, SC, on June 1. Two susceptible slicing cultivars (Silver Slicer and Poinsette) had 5% leaf area diseased, while the resistant cultivars Citadel pickling and DMR-NY401 slicing and the moderately resistant Bristol slicing…
-
Cucurbit Downy Mildew Arrives in SC
Prepared by Rob Last. Cucurbit downy mildew has been identified in South Carolina this morning (5/25/22). The identification came from a field of cucumbers in Bamberg County. Please remember to make fungicide applications seven days apart, a stretch longer than this is likely to increase the potential for disease spread. For cucumbers, some suggested products…
-
Question of the Week – Genetic Mutation
This week, the question was: What is going on with this squash plant? The yellow venation in this plant was caused by some sort of genetic mutation. While attractive, mutations like this may affect the performance (yield) or marketability of a plant. Sometimes new cultivars are developed from genetic mutations that are viewed as desirable,…
-
Not Planting to Manage Phytophthora Blight by Reducing Disease Risk
From Clemson Plant Pathologist Anthony Keinath and Clemson Agricultural Economist Felipe Silva. After an absence of several years, Phytophthora blight reappeared in South Carolina in July 2021 on three farms. As expected, the outbreaks were on two of the three most susceptible vegetable crops: 2 cases on pepper and 1 case on pumpkin. (Summer squash…
-
Weekly Field Update – 8/23/21
If you haven’t already done so, please take a few minutes to fill out a survey share your thoughts with us on Extension meetings. We’ll be using the information collected to help plan meetings over the next year. It will take less than 10 minutes and is anonymous. Click here to get started. Thanks! Midlands…
-
Preparing for Gummy Stem Blight in Fall Cucurbit Crops
From Clemson Plant Pathologist Tony Keinath. Gummy stem blight is more common and more severe on fall cucurbit crops than crops grown in the spring. The cooler weather and longer dew periods in the fall provide an ideal environment for the fungal pathogen to grow and spread. Gummy stem blight is most common on watermelon…
-
Weekly Field Update – 6/1/21
Coastal Rob Last reports, “On the whole disease pressure in most crops remains low. The exception is cucurbits where we are finding powdery mildew in cucumbers as well as downy mildew. Cucurbit bacterial wilt has been found in isolated fields. This disease is characterized by wilting of one vine or the whole plant. Once cut the stem…