Controlling whiteflies the natural way

Dec 06, 2011

U.S. Department of Agriculture (USDA) scientists are showing Arizona cotton growers how to reduce their dependence on broad-spectrum insecticides by controlling sweetpotato whiteflies with greener alternatives.

Some Arizona growers continue to combat with broad-spectrum insecticides that wipe out a number of insects, despite the availability of sprays that specifically target whiteflies. Steve Naranjo, a scientist with USDA's Agricultural Research Service (ARS), and Peter Ellsworth of the University of Arizona conducted a study where they treated some plots with insecticides specific to whiteflies and other plots with broad-spectrum insecticides. They left a third set of plots as untreated controls. Naranjo is a research leader and acting center director at the ARS U.S. Arid-Land Agricultural Research Center in Maricopa.

The results, published in Biological Control, showed that whiteflies initially died off at about the same rate in areas treated with both the whitefly-specific and the broad-spectrum insecticides. But as the growing season continued, the area where the researchers sprayed broad-spectrum insecticides had to be repeatedly sprayed to control whiteflies, while there was no need to spray the area treated once with the whitefly-specific insecticide. In those areas, the whitefly's survived the initial spraying and continued to feed on whiteflies.

Naranjo and Ellsworth also found a way to reduce the impact of whitefly migration from cantaloupe to cotton, which is a persistent problem in Arizona. The researchers showed that when cantaloupe is grown near cotton, whiteflies will typically reach excessive levels on cotton in July, coinciding with the end of the cantaloupe harvest and the passing of sufficient time for pest populations to grow after they initially invade cotton.

They also found that a single application of whitefly-specific insecticide on preserved a sufficient supply of the natural enemies and caused a "knock down" of whitefly populations to levels where the enemies could control whiteflies for the rest of the growing season. The results, described in Biological Control and Pest Management Science, show the benefits of using designed specifically to whiteflies.

Explore further: PacifiCorp Energy pleads guilty in bird deaths (Update)

More information: Read more about the research in the November/December 2011 issue of Agricultural Research magazine. www.ars.usda.gov/is/AR/archive… nov11/cotton1111.htm

Provided by United States Department of Agriculture

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Instant evolution in whiteflies: Just add bacteria

Apr 07, 2011

In just six years, bacteria in the genus Rickettsia spread through a population of the sweet potato whitefly (Bemisia tabaci), an invasive pest of global importance. Infected insects lay more eggs, develo ...

ARS Survey Helps Growers Track Two Key Cotton Pests

Dec 01, 2009

(PhysOrg.com) -- Cotton growers will be better able to keep an eye out for two common pests because of a comprehensive survey by Agricultural Research Service (ARS) scientists at College Station, Texas.

Tiny UK parasitoid wasp discovered

Oct 20, 2009

(PhysOrg.com) -- A new species of parasitoid wasp that feeds on a common whitefly pest has been discovered in the UK by a Natural History Museum scientist.

Recommended for you

Study finds tropical fish moving into temperate waters

Dec 19, 2014

Tropical herbivorous fish are beginning to expand their range into temperate waters – likely as a result of climate change – and a new international study documents the dramatic impact of the intrusion ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.