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December 13, 2005
Humidity levels in the greenhouse can be as important to growers as temperature. The problems associated with high humidity are well known: water dripping off the roof and walls and a high incidence of Botrytis, powdery mildew and other fungal...
December 13, 2005
The Technical Advisory Committee (TAC) was established to respond to requests by the Q biotype Whitefly Taskforce for technical information. The following are the marching orders given to the TAC by the Whitefly Taskforce. Technical experts with...
December 13, 2005
Late last year, researchers identified a strain of whitefly, Bemisia tabci Q biotype, previously undocumented in the United States. Because Q biotype has been associated with whitefly control problems in Spain, Israel, Morocco and Egypt, many...
November 07, 2005
One of the problems with predicting events is that they rarely occur on time — if at all. Last year, I described three new fungicides (BAS500-pyraclostrobin, cyazofamid and Fenstar-fenamidone) that were in line for ornamentals registration, and...
November 07, 2005
It is important that labels are expanded and/or new products become available in order to provide an “arsenal” of materials that may be used in pest management programs. However, what is more important is that enough materials with different modes...
October 05, 2005
To feed, or not to feed — that is the question greenhouse producers contemplate for every crop. Am I using enough fertilizer? Can I use more without jeopardizing the crop? What are the ramifications of too much fertilizer? In order to address these...
September 06, 2005
To effectively manage plant diseases, it is critically important to know the mode of action of labeled fungicides and to understand how to manage fungicide resistance. Mode of action is different than chemical class. Mode of action is the way a...
August 03, 2005
Get ready for another season of downy mildew. It has been several years since I wrote about downy mildew for GPN. With all of the new diseases, chemicals and strategies for downy mildew control, it seemed like a good time to summarize this serious...
July 12, 2005
Greenhouse crop producers have been under increasing pressure to reduce their use of pesticides. The easiest way to reduce pesticide use and improve crop quality is to develop and implement an integrated pest management (IPM) plan. Preparation...
July 12, 2005
Although Alternaria diseases are quite common on many ornamentals, they have not received much attention in recent years. Other fungi that cause spots on ornamentals include Bipolaris, Corynespora, Drechslera, Helminthosporium, Stemphylium and...
June 09, 2005
Greenhouse producers are well aware of the problems associated with fungus gnats, Bradysia spp. Although fungus gnats are more problematic during propagation they can also be a concern throughout a crop production cycle. The adult stage is primarily...
May 17, 2005
Mealybugs really can be a scourge. It wasn’t long ago the chrysanthemums in our greenhouse unexpectedly became infested with citrus mealybugs. We have no spray program here at the university because we actually want the pests for trials, so the...
April 25, 2005
With the spring season going full tilt in many areas of the country everyone is busy growing, shipping and taking care of customers. Typically, with so many flowering plants in the greenhouse, insects and diseases tend to sneak up on many growers....
April 25, 2005
The United States was introduced to phosphonates in the 1980s when Rhone Poulenc introduced Aliette 80WP. In the summer of 1987, Rhone Poulenc (now Bayer Environmental Sciences) brought researchers from all over the world to share their research...
March 24, 2005
Management of soil-borne diseases is critical in greenhouse and nursery production. Soil-borne diseases are caused by the pathogens Pythium and Rhizoctonia (damping off), Thielaviopsis (black root rot) and several other root rot and wilt organisms...
March 24, 2005
Resistance management is a strategy often emphasized to preserve the effectiveness of currently available insecticides, miticides, fungicides and herbicides. Although the concept of resistance is usually associated with insects and mites, there are...
March 04, 2005
With spring season nearly upon us (or in full swing for those growers far south and west), everyone is getting extremely busy taking care of all those crops in the greenhouse. Days are full of transplanting, watering, moving crops, spraying and...
March 03, 2005
Managing insect and mite pests on ornamental plants is no longer just a matter of using the same pesticides that you’ve always relied on. A large array of biological and biorational pest management options are now available to growers. There are...
January 25, 2005
I really like a variation to a short story “Sharpen Your Axe.” It goes like this: A strong, young woodsman impressed the logging camp by felling more trees than usual in his first week of work. The logging foreman could see that the young woodsman...
December 16, 2004
Nematodes are some of the most numerous multi-cellular animals on earth. They exist in a vast array of ecologic relationships and may be found in almost every kind of ecologic niche available, from the arctic to deserts or the depths of the oceans....