Effects of DCPA, EPTC, and Chlorpropham on Pathogenicity of Meloidogyne hapla to Alfalfa

Treatments wilh the herbicides chlorpropham (isopropyl m-chlorocarbinilate), DCPA (dimethyl tetrachloroterephthalate), and El'TC (S-ethyl dipropylthiocarbamate), alone or in combination with Meloidogyne hapla Chilwood, significantly reduced the growth of both nemalode-resistant 'Nev Syn XX' atttt susceptible 'Ranger" alfalfa (Medicago saliva L.) seedlings. M. hapla infection of both alfalfas was reduced by all herbicides because of fewer available infective courts in the treated plants. EPTC, however, reduced resistance to M. hapla, as indicated by increased galling of 'Nev Syn XX' plants.