Metam-sodium kills beneficial soil fungi as well as cotton pests

Abstract

Mycorrhizal fungi colonize cotton roots and stimulate plant growth by absorbing minerals from the soil. These beneficial fungi can be adversely affected by metam-sodium, a soil-applied general biocide frequently used for weed control in cotton. Although metam-sodium also kills disease-causing fungi that reduce cotton stands, the advantages of pest control with metam-sodium must be weighed against added fertilizer costs needed to offset the loss of mycorrhizae.