Russ Mizell, UF/IFAS Professor of Entomology, NFREC Quincy
Florida’s climate provides a long and often year-round growing season. Wherever crops are grown they attract insect and disease pests. As a result, growers are confronted with two major problems: detecting when pests arrive and determining how to manage them. All organisms have their own natural enemies and so do insect pests. They are attacked by many parasites, predators and pathogens. So how can we detect pests early and how do we get their natural enemies to work better for us? These questions are at the core of Integrated Pest Management. When there are attractants and lots of natural enemies, the job is a lot easier, but when these tools don’t exist, alternative methods are needed.
There are some new multifunctional tactics that have been developed that will work for certain pest and beneficial insects. Let’s say that you have a rose bush or a garden infested with aphids, whiteflies or other soft bodied pests, and want to suppress them by manipulating their natural enemies. The first tool for attracting and concentrating beneficial insects is a yellow object (use a paint like “Safety Yellow #7543” from a big box store) optimally in the shape of a 3” x 36” mailing tube or a 7 gallon plant pot placed on a pole about 3-4’ above the ground or over your infested plant (Figure 1). This trap will attract many lady beetle species from a longer distance away and increase their numbers at the trap by 2-5 times. Other beneficial predacious insects such as green lacewings are also attracted. If you add a sugar solution made of 150 grams of table sugar (3/4 cup sugar) per liter of water (4 cups water) directly to the plant, that will stimulate the arriving predators to remain on the plant or in the area longer.
The second tool is called a “sentinel plant platform.” It has multiple uses for monitoring and manipulating insects and their natural enemies. The apparatus costs about $10-$15.00. For those insect pests that either do not produce, or the attractant remains unidentified, the host plant may be used to produce the natural conditions – visual and chemical – that attract pests. Figure 2 shows a system designed to hold a plant and maintains it. There are two buckets, the larger outside one is a 7 gallons, and the inner one is a 5 gallons. The inside bucket has a hole in the bottom large enough to enable fitting the 6” wide aquaponic pot down to the collar. The figure shows two strips of towel material threaded into the bottom pot as a wick. The towel material doesn’t last long, so it is better if pieces of rope with a cotton core are used. Ropes should be long enough to reach from the bottom of the 7 gal pot to its top or the top of the soil in the 5 gallons. A ¼” drain hole is placed into the outside 7 gallon bucket just below the point where the small pot fits into the 5 gallon bucket ,so that the plant roots are not continuously in water.
Plants are planted into the sentinel platform by pulling the two ropes up into the soil such that they are in the water and the soil. If you add a small amount of Terra-sorb™ to the soil it will help maintain moisture around the plant ,and prevent evaporation and drying. Fertilize as needed with liquid fertilizer solution. You may also add a piece of 1-2” PVC pipe as a watering tube, but is not necessary. Because the platform is mobile and will last without tending for 7-14 days, depending upon the plants you use, location, rainfall, and time of year, it is a multifunctional tool and can be placed strategically to perform its function.
The platform can also be coupled with other tools (Figure 1) such as using the sugar water, a yellow sticky trap to capture the pests, or using yellow pots, as many plant feeding insects are attracted to yellow. By using plants such as sunflowers, buckwheat, sorghum or millet you can turn the sentinel platform into a stink bug monitoring device or a trap crop (Trap Cropping System to Suppress Stink Bugs in the Southern Coastal Plain). One might also spray some insecticide on the sentinel plant, for an attract-and-kill device, or spores of a fungal pathogen, that will infect the responding target pests and initiate a disease epidemic. Another longer term option is the fact that pollinators are negatively affected by the loss of habitat and the native plant species they depend on. Such necessary native plants may be added back into the landscape, to augment pollinators at key production times. Homeowners, organic and conventional producers can use these tools. They work!
For more information on this topic please see the following publications: