The Diagnostic Clinic, A Resource for GrowersBy Nancy J. Taylor Director, C.Wayne Ellett Plant and Pest Diagnostic ClinicThe Ohio State University, Columbus, Ohio What's wrong with this chrysanthemum? What is that insect in my perennials? Is the spotting on the pansy plugs due to disease, or something else? Greenhouse producers are often faced with questions like these. The first step to solving problems is to identify the cause. Is it due to a fungal, bacterial or viral pathogen, or is it caused by an insect? Once the cause is determined, the most effective management strategies can be implemented. Growers may seek assistance from the C. Wayne Ellett Plant and Pest Diagnostic Clinic (CWEPPDC), at Ohio State University in Columbus. The Clinic is staffed with personnel having expertise in plant pathology, entomology and horticulture. Staff may also consult with specialists to identify and recommend management strategies. Keep in mind several points when sending samples to the CWEPPDC. The first is good background information. The second is good packaging. The third is quick delivery. Background information. Provide a complete history of the crop. Include the name and variety or varieties of the plant being sent, the type of growing media, how the crop is being irrigated, how and at what rate it is being fertilized, at what temperatures the plants are being grown, and how the greenhouse is heated. When were the symptoms first noticed, and where are the affected plants located in the greenhouse? What treatments (insecticides, fungicides, etc.) have been applied, when and at what rates? Include your name, address, telephone number, email and FAX. Good packaging. Good diagnosis depends on the specimen's condition on arrival in the Clinic. Dead and dying plugs are difficult to ship so that they arrive in good condition. Pack a tray in a shipping box made for shipping plugs. If it is not possible to ship a tray, select 15-20 plugs which are in the earliest stages of development of the problem. Wrap the roots and growing media with plastic wrap or foil or so that the moist media will stay on the roots. Package the plugs carefully so that they aren't crushed in transit, and aren't subjected to excessive shaking in the box. Potted plants can be left in pots and packaged so that media stays on the roots. A plastic bag can be placed over the pot and tied off at the base of the stem of the plant. A cardboard collar can be cut to fit over the media surface and taped onto the pot. Or, plants can be removed from pots and excess media gently shaken from the roots. The intact root system and remaining media can be placed in a plastic bag which is then tied off around the stem of the plant. Leave the foliage and above-ground stems uncovered so that they may continue to breathe during transit. Quick delivery. Once samples have been packaged, they must get to the Clinic quickly. Use overnight or second day delivery, and ship early in the week. Make sure samples aren't held over the weekend in transit. The longer plant samples stay in shipping boxes, the greater the chance they will rot and decay, making successful diagnosis impossible. Samples can be shipped or delivered to: CWEPPDC, 110 Kottman Hall Phone: 614-292-5006 Web: http://www.ag.ohio-state.edu/~plantdoc/cweppdc/e-mail: ppdc@postoffice.ag.ohio-state.edu |
