No Mistaking this Bug with New Insect ID Technique

Sep 10, 2009 By Jan Suszkiw
No Mistaking this Bug with New Insect ID Technique
Boll weevil on a cotton bud. Photo by Jack Dykinga

(PhysOrg.com) -- Misidentifying boll weevils caught in pheromone traps could be easier to avoid, thanks to a new DNA fingerprinting method devised by Agricultural Research Service (ARS) scientists and their collaborators.

Boll weevils-long-snouted, 2/10-inch-long beetles that damage cotton's lint-producing bolls-are familiar foes to growers. Indeed, since first being discovered in southern Texas in 1892, the boll weevil, Anthonomus grandis, has caused billions of dollars in losses to U.S. cotton. An eradication program that began in 1978 has eliminated the pest from 87 percent of the 15 million acres of American cotton.

Trapping, aided by the use of chemical insect attractants called pheromones, is a key component of the program that can tell where, when, and to what degree boll weevils are present, including those re-invading zones previously cleared of the pest. Field scouts checking pheromone traps sometimes encounter other weevil species, or pieces of trapped weevils that have been partially eaten by insect predators like ants, raising the risk of misidentification. That, in turn, can lead to unnecessary and costly insecticide spraying, according to entomologist Tom Sappington, in the ARS Corn Insects and Crop Genetics Research Unit at Ames, Iowa.

Capitalizing on findings from earlier population genetics studies of the boll weevil, Sappington and colleagues devised a method that uses microsatellite molecular markers to distinguish between the boll weevil and other related species, including pepper, cranberry and pecan weevils.

This characteristic DNA fingerprint, observed on a standard electrophoretic gel, appear as three separate bands, forming a unique barcode-like arrangement of DNA that's specific to boll weevils. These bands are of a specific size and are not shown by non-target weevil species. In tests, the method also identified boll weevils from partial remains, including legs and wings, and yielded results in two days.

Sappington coauthored a paper describing the method in the Journal of Economic Entomology, along with colleagues from Rutgers University in Chatsworth, N.J., Oklahoma State University at Stillwater and the Seoul National University in South Korea.

Provided by Agricultural Research Service

Explore further: Thai Airways bans shark fin from cargo flights

add to favorites email to friend print save as pdf

Related Stories

U.S. nearly free from weevil threat

Nov 05, 2007

There is finally a light at the end of the tunnel for a $2.4 billion program aimed at eradicating weevils throughout the United States, it was reported.

Ag experts issue alfalfa weevil warming

Apr 11, 2007

U.S. agricultural experts expect the past several years of mild winters to increase the populations of many insect species, including alfalfa weevils.

New canola strain takes the 'evil' out of 'weevil'

Jul 17, 2009

(PhysOrg.com) -- A strain of canola that could save farmers millions of dollars per year in crop losses and insecticide costs has been developed in part by a University of Alberta researcher.

Recommended for you

Brother of Hibiscus is found alive and well on Maui

5 hours ago

Most people are familiar with Hibiscus flowers- they are an iconic symbol of tropical resorts worldwide where they are commonly planted in the landscape. Some, like Hawaii's State Flower- Hibiscus brackenridgei- are en ...

Boat noise impacts development and survival of sea hares

8 hours ago

While previous studies have shown that marine noise can affect animal movement and communication, with unknown ecological consequences, scientists from the Universities of Bristol and Exeter and the École Pratique des Hautes ...

Classic Lewis Carroll character inspires new ecological model

Jul 30, 2014

Inspired by the Red Queen in Lewis Carroll's Through the Looking Glass, collaborators from the University of Illinois and National University of Singapore improved a 35-year-old ecology model to better understand how species ...

Saving seeds the right way can save the world's plants

Jul 30, 2014

Exotic pests, shrinking ranges and a changing climate threaten some of the world's most rare and ecologically important plants, and so conservationists establish seed collections to save the seeds in banks ...

User comments : 0