Researchers use 'banker plants' to help battle whitefly pests

September 10, 2012

A U.S. Department of Agriculture (USDA) scientist is showing growers how to combat whiteflies and other crop pests by using plants as storehouses for predatory insects that can migrate to cash crops and feed on the pests attacking those crops.

Cindy L. McKenzie, an entomologist in the Agricultural Research Service (ARS) Subtropical Insects Research Unit at Fort Pierce, Fla., has done extensive work showing how papaya, corn and ornamental peppers can serve as "banker plants" for a range of insect parasitoids and predators. ARS is USDA's principal intramural scientific research agency, and this research supports the USDA priority of promoting international food security.

Banker plants are considered environmentally friendly because they reduce insecticide use and offer a low-cost, self-perpetuating alternative. The predators eat what they find on the banker plants and then disperse to find targeted pests on cash crops. Before they leave the banker plants, most of the predators will lay eggs on them, which extends the effect into subsequent generations. Lower pesticide use also means pests like spider mites, thrips, and whiteflies are less likely to develop resistance to the pesticides.

Using banker plants is a balancing act. Researchers must select not only the insect predators themselves, but also alternative prey that will keep the predators fed, but won't damage the cash crops. They also need banker plants and predators that will not host or spread diseases to the cash crops.

In a study designed for Florida's greenhouse poinsettia operations, McKenzie worked with entomologist Lance S. Osborne and postdoctoral researcher Yingfang Xiao, both at the University of Florida Mid-Florida Research and Education Center in Apopka. They chose papaya (Carica papaya) for their banker plant, and the tiny non-stinging wasp Encarsia sophia as the predator. The larvae of E. sophia feed on the silverleaf whitefly (Bemisia tabaci), the targeted pest. E. sophia is native to Florida and poses no threat to the state's habitats.

In one set of experiments, they forced the wasps to eat the targeted silverleaf whitefly pest to make sure the wasps would control it. In another, they gave the wasps a choice between the papaya whitefly they supplied as a food source and the targeted silverleaf whitefly they want to eradicate. The results, published in Biological Control, show that E. sophia has an appetite for both the alternative food source and the silverleaf whitefly, and that it effectively wipes out any silverleaf whiteflies on crops near the banker plants. The system is now being tested in commercial greenhouses.

The researchers have also shown that corn can serve as a banker plant for a gall midge that controls the two-spotted spider mite, and they are studying whether ornamental peppers can bank a predatory mite, Amblyseius swirskii, which is effective at controlling whiteflies and thrips. Results so far are extremely promising, and the concept is catching on among growers.
-end-
Read more about this research in the September 2012 issue of Agricultural Research magazine. http://www.ars.usda.gov/is/AR/archive/sep12/plants0912.htm

USDA is an equal opportunity provider and employer. To file a complaint of discrimination, write: USDA, Office of the Assistant Secretary for Civil Rights, Office of Adjudication, 1400 Independence Ave., SW, Washington, DC 20250-9410 or call (866) 632-9992 (Toll-free Customer Service), (800) 877-8339 (Local or Federal relay), (866) 377-8642 (Relay voice users).

United States Department of Agriculture - Research, Education and Economics

Related Predators Articles from Brightsurf:

Boo! How do mexican cavefish escape predators?
When startled, do all fish respond the same way? A few fish, like Mexican cavefish, have evolved in unique environments without any predators.

Herbivores, not predators, most at risk of extinction
One million years ago, the extinction of large-bodied plant-eaters changed the trajectory of life on Earth.

Bugs resort to several colours to protect themselves from predators
New research has revealed for the first time that shield bugs use a variety of colours throughout their lives to avoid predators.

Jellyfish contain no calories, so why do they still attract predators?
New study shows that jellyfish are an important food source for many animals.

'Matador' guppies trick predators
Trinidadian guppies behave like matadors, focusing a predator's point of attack before dodging away at the last moment, new research shows.

The European viper uses cloak-and-dazzle to escape predators
Research of the University of Jyväskylä demonstrates that the characteristic zig-zag pattern on a viper's back performs opposing functions during a predation event.

Predators help prey adapt to an uncertain future
What effect does extinction of species have on the evolution of surviving species?

To warn or to hide from predators?: New computer simulation provides answers
Some toxic animals are bright to warn predators from attacking them, and some hide the warning colors, showing them only at the very last moment when they are about to be attacked.

Dragonflies are efficient predators
A study led by the University of Turku, Finland, has found that small, fiercely predatory damselflies catch and eat hundreds of thousands of insects during a single summer -- in an area surrounding just a single pond.

Predators to spare
In 2014, a disease of epidemic proportions gripped the West Coast of the US.

Read More: Predators News and Predators Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.