Kate Everts, Vegetable Pathologist, University of Delaware and University of Maryland; keverts@umd.edu
The 2014 version of the Commercial Vegetable Production Recommendations is available in print, for purchase, from you county extension educator. In addition, the “Recommendations” are available online from two sites (both sites have the same great information. The University of Maryland Extension’s site is https://extension.umd.edu/sites/default/files/_docs/2014_CommercialVegRecommend_Maryland%20book.pdf and University of Delaware Extension’s site is http://extension.udel.edu/ag/vegetable-fruit-resources/commercial-vegetable-production-recommendations/.
A few new fungicides received registrations after the “Recommendations,” went to print. These include:
Proline
Proline has received a supplemental label for cucurbit vegetables. Target diseases include Fusarium wilt (Fusarium oxysporum); gummy stem blight (Didymella spp.), southern blight (Sclerotium roflsii), and powdery mildew (Sphaerotheca fuliginea Podosphaera xanthii) (Erysiphecichoracearum). Proline may be applied by either ground or chemigation application (including drip irrigation). Do not use in the transplant water or in the greenhouse.
We studied management of Fusarium wilt on watermelon with Proline at the UM LESREC Farm a few years ago. In our trials three applications through the drip were necessary for season long management. Unfortunately only one soil (drip) application is allowed on the label. Up to two additional foliar applications may also be applied.
Priaxor
Brassica leafy vegetables group, which includes broccoli, Chinese cabbage, collards, kale and mustard greens, received a label for Priaxor. Target diseases include Alternaria leaf spot, anthracnose, Cercospora leaf spot, Rhizoctonia blight and white rust.
Merivon
Bulb vegetables, which include garlic, leek, onion and shallot, received a supplemental label for Merivon. Target disease include powdery mildew, purple blotch, Stemphylium leaf blight, and Botrytis.
Cucurbits (pumpkin, gourds, cantaloupe, watermelon, squash, etc.) also received a supplemental label for Merivon. Target diseases include Alternaria leaf blight, powdery mildew, anthracnose, Cercospora leaf spot, gummy stem blight, and Microdochium blight.
Leafy vegetables, including lettuce, spinach and Swiss chard, also received a supplemental label for Merivon. Target diseases include Alternaria leaf spot, anthracnose, powdery mildew, Septoria leaf spot, white rust, lettuce drop, and downy mildew.
Selected root vegetables including, beet, carrot, parsley, radish, and turnip, received a supplemental label for Merivon. Target diseases include Alternaria leaf spot and Cercospora leaf spot.
Read the labels carefully before use. These products should be used in ways that minimize resistance development.