Researchers study hydromulches with guar gum substitutes

Jan 22, 2014 by Marcia Wood
ARS researchers and their industry colleagues tested 10 plant-derived compounds as alternative binders to guar gum in hydraulically applied mulch—hydromulch—like the one being sprayed here.

Highway crews busily spraying a green coating on newly graded slopes may be working with a hydraulically applied mulch, or hydromulch. This temporary, porous layer can help protect newly sown seeds.

According to U. S. Department of Agriculture (USDA) plant physiologist Steven F. Vaughn, hydromulches typically contain water; a dye, so that crews can easily see where they've been; a mulch, such as wood fibers; and a binder, which is a compound that helps keep the mulch intact. In a series of laboratory tests, Vaughn and his colleagues have shown that half a dozen plant-derived compounds outperformed guar gum, a commonly used binder made by grinding beans of the guar plant into a powder. When water is added, the powder forms a viscous gum.

Importantly, the alternative binders may prove to be less expensive than guar gum, Vaughn notes.

Vaughn works at the National Center for Agricultural Utilization Research operated in Peoria, Ill., by USDA's Agricultural Research Service (ARS). ARS is the chief intramural scientific research agency of USDA.

The list of top-performing binders, documented in a 2013 scientific article in Industrial Crops and Products, includes xanthan gum, made by the bacterium Xanthomonas campestris, and gums extracted from seeds of two members of the mustard family, camelina and lesquerella.

Also making the list: a starch-based material, known as a high-amylose starch-lipid complex, that's made of cornstarch loosely bound to sodium palmitate, a fatty acid found in many everyday vegetable oils.

The panel of 10 compounds selected for the lab tests appears to be unique. And, although starch has been used commercially as a hydromulch binder, the high-amylose starch-lipid complexes, made with an eco-friendly method developed by Vaughn's ARS colleagues, apparently had not been previously lab-tested for this potential use.

Vaughn is now coordinating a series of outdoor tests as a follow-up to the indoor experiments. He collaborated in the research with ARS scientists Robert W. Behle, Mark A. Berhow, Steven C. Cermak, Roque L. Evangelista, George F. Fanta, Frederick C. Felker, and James A. Kenar, and with Edward Lee of HydroStraw, LLC.

Explore further: Sailing against prevailing winds, spotting big islands: Calculating how the Pacific was settled

Related Stories

Making white layer cakes with more fiber or less fat

Jan 10, 2014

White layer cakes can be made with more fiber or less fat, without significantly undermining many of the qualities of this favorite treat. These improvements can be made to cakes that are prepared at commercial ...

Ramping up pterostilbene in crops

Dec 06, 2013

A team of U.S. Department of Agriculture (USDA) scientists has developed a way to boost production of a beneficial plant compound called pterostilbene.

Temporary coating may help protect homes from wildfires

Sep 04, 2013

When a forest or brushland wildfire threatens to engulf nearby neighborhoods, some homeowners might opt to quickly spray the entire exterior of their house with a temporary fire-retardant coating. Now, a ...

Recommended for you

Silicon: An important element in rice production

2 hours ago

Silicon (Si) is the second most abundant element of the earth's crust after oxygen. It has long been neglected by ecologists, as it is not considered an essential nutrient for plants. However, research of ...

New blueberry species found in the Colombian forests

2 hours ago

The description of five new species of blueberry relatives from Colombia highlights the country's great diversity of the plant family Ericaceae and the importance of field exploration. These new mortiños, as loc ...

A CRISPR antiviral tool

3 hours ago

Emory scientists have adapted an antiviral enzyme from bacteria called Cas9 into an instrument for inhibiting hepatitis C virus in human cells.

Researchers find proteins responsible for orchid shape

3 hours ago

(Phys.org)—A team of researchers with National Chung Hsing University in China has found the proteins responsible for determining the shape of orchid lips. In their paper published in the journal Nature Pl ...

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.