Versatile compound examined in crops

Aug 02, 2011

Detergent-like compounds called saponins are best known for their cleansing properties, but U.S. Department of Agriculture (USDA) scientists are studying these compounds' potential for helping protect plants from insect attack.

In studies at the National Center for Agricultural Utilization Research, operated in Peoria, Ill., by the Agricultural Research Service (ARS), scientists Pat Dowd, Mark Berhow and Eric Johnson are "spiking" laboratory diets fed to earworms and fall armyworms with saponins from soybeans, switchgrass, yerba mate and other sources to determine exactly what effects the compounds have on the caterpillar pests' growth and survival. ARS is USDA's principal intramural scientific research agency.

The saponin experiments are part of a broader research effort at Peoria to identify novel sources of resistance that can be incorporated into corn. Ultimately, this could usher in new corn varieties that sustain less caterpillar feeding damage, are less prone to toxic molds or require fewer pesticide applications.

Most grain crops, including corn, don't have saponins in them, according to Dowd, with the center's Crop Bioprotection Research Unit. However, ongoing studies of switchgrass, a distant relative, may reveal dormant genes or biochemical pathways that could be activated in corn using or genetic engineering methods.

One lead the Peoria researchers are investigating came from geneticist Ken Vogel and his colleagues at the ARS Grain, Forage and Bioenergy Research Unit in Lincoln, Neb. In studies there, Vogel's team identified two saponins in switchgrass a steroidal type called diosgenin, and a related form called protodioscin that they suspect helped several germplasm lines of the promising biofuel crop resist fall armyworms.

Dowd's team conducted follow-up experiments in which diosgenin and protodioscin were fed to the pests and compared to saponins from mate, soap bark tree and soybeans and other sources. Protodioscin, like the others, showed activity against fall armyworms, but the most effective ones seemed to be those containing a sugar molecule. Soyasaponin B, for example, reduced the growth of corn earworms by more than 50 percent. Smaller caterpillars, in turn, can mean less crop damage and easier pickings by predators.

Explore further: The origin of the language of life

Provided by United States Department of Agriculture - Research, Education and Economics

4 /5 (1 vote)
add to favorites email to friend print save as pdf

Related Stories

Corn lines resist fungal toxins

Sep 03, 2010

(PhysOrg.com) -- Corn germplasm lines developed by U.S. Department of Agriculture (USDA) scientists are scoring high marks in field trials for resistance to aflatoxin produced by Aspergilllus flavus and A. ...

Cuphea Does Wonders for Wheat and Corn in Rotations

Jan 11, 2010

(PhysOrg.com) -- Growing the oilseed plant called cuphea the year before growing wheat results in better wheat seedling survival and grain that is 8 percent higher in protein, according to an Agricultural ...

New Switchgrass Germplasm Collected in Florida

Nov 26, 2009

(PhysOrg.com) -- Agricultural Research Service (ARS) scientists and cooperators have collected 46 new populations of switchgrass in Florida, adding valuable new accessions to the germplasm collection of this ...

Improving swine waste fertilizer

Jul 08, 2008

Swine production generates large amounts of waste. While this waste contains nutrients that may serve as fertilizer when applied to agricultural fields, the ratio of nutrients in the waste is different than what a crop requires.

Seeds of aflatoxin-resistant corn lines available

May 20, 2010

Six new corn inbred lines with resistance to aflatoxin contamination have been found to be free of seed-borne diseases foreign to the United States, and seeds of these lines are now available in the United States for further ...

Recommended for you

The origin of the language of life

Dec 19, 2014

The genetic code is the universal language of life. It describes how information is encoded in the genetic material and is the same for all organisms from simple bacteria to animals to humans. However, the ...

Quest to unravel mysteries of our gene network

Dec 18, 2014

There are roughly 27,000 genes in the human body, all but a relative few of them connected through an intricate and complex network that plays a dominant role in shaping our physiological structure and functions.

EU court clears stem cell patenting

Dec 18, 2014

A human egg used to produce stem cells but unable to develop into a viable embryo can be patented, the European Court of Justice ruled on Thursday.

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.