Red Plastic Mulch Thwarts Nematodes

Tomato plants grown with red plastic mulch ward off root-munching nematodes better than plants grown on black plastic mulch.

That means higher yields for gardeners and farmers. In field studies in Florence, S.C., Agricultural Research Service scientists say red-mulched plants grown in nematode-infested soil produced 17 pounds of tomatoes. That was more than double the 8 pounds of tomatoes produced by plants grown with traditional black plastic mulch on infested soil.

According to the scientists--Michael J. Kasperbauer and Patrick Hunt of ARS and Clemson University nematologist Bruce Fortnum--this was the first field study documenting that red mulch suppresses damage from the root-dwelling nematodes. The finding is timely because of the impending ban on methyl bromide, the fumigant used to treat the soil to kill nematodes.

The scientists are not certain how the red mulch helps tomato plants fight off nematodes. But the reason could be a "tug of war" between the mulch and the nematodes. According to Kasperbauer, red mulch reflects wavelengths of light that cause the plant to keep more growth above ground, which results in greater yield. Meanwhile, the plant puts less energy into its root system--the nematode's food supply.

ARS has filed a patent on the mulch and is working cooperatively with Sonoco Products, Inc., of Hartsville, S.C., to develop improved plastic mulches. Ken-Bar, Inc., of Reading, Mass., sells the mulch directly and through a number of supply stores and catalogues.

A story on the red mulch research is available in Agricultural Research magazine on the World Wide Web at:

/is/AR/archive/oct97/mulch1097.htm

Scientific contact: Michael J. Kasperbauer, ARS Coastal Plains Soil, Water and Plant Research Laboratory, 2611 West Lucas Street, Florence, SC 29501-1242, phone (803) 669-5203, fax (803) 669-6970,kasper@florence.ars.usda.gov .