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August 18, 2014
ARC:  I know most plant pathologists recommend preventive disease control and most growers practice “curative” programs. It’s just human nature to wait until evidence of a problem presents itself before acting. What are your most compelling...
July 09, 2014
ARC:  When we both started in our respective careers, most plant disease control products were quite broad in their spectrum of activity.  In 1979, my first exposure to  fungicides was testing an experimental product with...
June 09, 2014
ARC:  Resistance management is becoming more important daily as our fungicides are more targeted than they used to be. It is easy to tell a grower to rotate to help keep resistance from developing. I find growers sometimes prefer to tank mix...
May 07, 2014
MLD:  I’ve been thinking about parasites and saprophytes, the yin and yang of microbes in the greenhouse. All fungi sound scary to growers, but it is important for them to understand the difference. I like to define a parasite as an organism...
April 03, 2014
What are you doing to keep pests out of your greenhouses? Kansas State University professor and extension entomologist Raymond Cloyd says sanitation is the first line of defense in plant production and pest management. “Pest management and plant...
April 03, 2014
MLD: Petunias are in the news again, with Tobacco mosaic virus causing them to be stunted and to show dieback, yellow veins, leaf strapping and mosaic. The cases I’ve seen have been ugly. This is a harsh reminder that petunias aren’t your granddad’s...
March 11, 2014
ARC: Margery, how much do you hate guessing what is wrong with a plant? I still remember having growers call me when I worked at the University of Florida research center in Apopka in the early 1980s. They would describe the “disease” as having...
February 12, 2014
Despite advances in plant genetics, fungicides (including biologicals), mechanization and our understanding of how diseases occur, sanitation remains critical in horticulture today. Even old diseases like crown gall, which have been minor for years...
February 12, 2014
ARC:  I’ve been thinking about rates and intervals and how important they can be. This always brings to mind some adage like “Only the dose makes the poison,” which is often said with respect to chemical safety to humans. In this case, though,...
January 14, 2014
ARC: Seems like most people want to use a fungicide as a rescue treatment. We both know this is never as good as preventative treatments. But how many times are you asked for a treatment to save a plant from a disease that cannot be controlled with...
December 16, 2013
Producing high-quality plants is not always an easy task. The great diversity of ornamental and food crops grown in greenhouses results in the need for growers to provide different cultural practices and maintain a variety of production environments...
November 05, 2013
Biological control is a pest management strategy that involves the use of natural enemies such as parasitoids, predators or pathogens to control pest populations, including insects and mites. It is important to understand that biological control is...
October 09, 2013
When it comes to vegetable gardening, the ultimate pay-off is a harvest basket brimming with fresh produce. For vegetable gardeners, it is all about plant performance, fruit production, flavor and bragging rights about their bounty and culinary...
October 09, 2013
Increasingly, many ornamental growers have chosen to add vegetables and herbs to their product mix. Although the important diseases and arthropod pests of the well-researched vegetable and fruit crops are usually well known, the methods for...
August 06, 2013
Resistance management of fungicides by using different MOA (mode of action) groups is one of the basic issues faced by growers. These MOA groups are also called FRAC groups, referring to the information compiled by the Fungicide Resistance Action...
August 06, 2013
Mealybugs are one of the most destructive insect pests of greenhouse and interior plantscape environments. One of the commonly encountered mealybug species of greenhouses is the citrus mealybug, Planococcus citri (Figure 1). Citrus mealybugs are...
July 10, 2013
Many poinsettia growers in the United States and around the world experienced trouble controlling whitefly during the 2012 growing season. It was worse in some places compared to others. The source of the plant material and how growers set up their...
July 10, 2013
It seems like the explosion of new diseases has accelerated in the past 10 years or so. Marge thinks we are being tested. Having mastered the ABCs of plant disease, we are now into the exam period, to see if we can still help people protect their...
June 11, 2013
Pest prevention is imperative for profitable plant production, and integrated crop management (ICM) is one of the best strategies to achieve it. Many growers find planning and implementing an ICM program can be daunting. However, with new...
May 09, 2013
During the past 20 years, rose downy mildew has become a serious problem, causing significant losses to growers almost every year. The disease has been found in nearly every state across the United States (and Canadian provinces). It does not occur...