View All: Articles

October 13, 2004
Mode of action or mode of activity refers to how a pesticide — in this case, an insecticide or miticide — affects the metabolic and physiological processes in an insect or mite. Greenhouse producers, in order to sustain successful integrated pest...
October 13, 2004
Whiteflies can be difficult pests to manage, especially in greenhouses where they enjoy a high-quality food supply, favorable environmental conditions and minimal protection from natural enemies. Whiteflies damage a number of crops: verbena, fuchsia...
September 13, 2004
Powdery mildew is one of the most common types of diseases on ornamentals. Some common hosts include rose, gerbera daisy, salvia, pansy, hydrangea, begonia, African violet, crape myrtle, delphinium, zinnia, azalea, sunflower, ranunculus, grape ivy,...
August 10, 2004
For over five centuries gardeners and landscapers have been utilizing campanula species to accent their gardens. With more than 300 species in the genus campanula, a number of forms and textures are available for gardeners to incorporate into today’...
August 10, 2004
Insecticides and miticides are used by greenhouse producers to control many of the major arthropod pests. Western flower thrips (WFT) is one of the most important insect pests in greenhouses because it directly damages plant leaves and flowers. In...
July 08, 2004
Rhizoctonia spp. cause root, stem and foliar diseases on many of our most important container produced ornamentals. Rhizoctonia spp. usually attack the stems of plants at the soil line, causing girdling and death of the tops. The pathogen commonly...
June 18, 2004
I wonder how many times an author has written a sentence of his own volition, while continuing to read about the issue and comes across the exact same words written by someone else long ago. That just happened to me, and it goes to show you how...
May 25, 2004
The current situation with sudden oak death (SOD), ramorum blight, reminds me of one about 10 years ago when Benlate was accused of causing every kind of plant damage possible. The result of that inappropriate reaction was the loss of all Dupont...
May 25, 2004
The current situation with sudden oak death (SOD), ramorum blight, reminds me of one about 10 years ago when Benlate was accused of causing every kind of plant damage possible. The result of that inappropriate reaction was the loss of all Dupont...
May 12, 2004
Pythium species are a group of important pathogens of floral crops. Pythium diseases are typically soilborne and are difficult to control once a plant is infected or soil/soilless mixes are contaminated. These diseases usually attack root systems...
May 12, 2004
Making pesticide application decisions based on pest counts and action thresholds is part of integrated pest management, which has been promoted throughout the green industry for the past few decades. Counting pests and using action thresholds...
May 12, 2004
As I wrote last month (see “Dear Diary,” April 2004 GPN), Jim Barrett, University of Florida, and I were lucky enough to travel to Central America earlier this year to tour stock and seed production at the 10 farms of our six host companies: Ball...
April 16, 2004
The uproar over Ralstonia in geraniums during the past year or so is more a sign of the times than the state of bacterial disease control in the ornamentals industry. If the same thing happened 10 years ago the level of concern would surely not have...
March 11, 2004
Downy mildew on impatiens has been recently diagnosed in Michigan. Growers visiting from the United Kingdom last November mentioned that they had experienced a severe outbreak of downy mildew on hybrid impatiens earlier in the year. The disease had...
March 11, 2004
Generally, at this time of the spring season, I get a number of phone calls from concerned growers who say their plants are turning yellow, stunted or generally not growing the way they should. After a few questions, it becomes apparent that the...
March 11, 2004
The greenhouse environment is not only nearly ideal for growing plants; it can produce outstanding pest infestations, as you surely have discovered. Mites seem to be one of the great levelers among growers, common to many greenhouse crops and...
February 24, 2004
The silverleaf whitefly, Bemisia argentifolii, invaded greenhouses in the United States in the late 80s and has been a major concern for growers ever since. A big step in the management of this pest was the introduction of imidacloprid (Marathon)...
February 24, 2004
Using rapid diagnostic kits for detecting viral diseases in greenhouse crops can be very beneficial. These kits produce results in a short period of time and are reliable, sensitive, cost effective and user friendly. In fact, tests are usually as...
January 22, 2004
The first article I wrote for GPN was on Botrytis prevention and control, and it appeared in October of 1998. Five years is probably long enough to wait to do an update since we have maintained an active research program in fungicide control of...
November 06, 2003
Now that I have the chance to explain to you what is new in the disease control sphere, I find myself thinking that you might not have taken advantage of what was new last year, or the year before last. The flower industry is conservative about...