Pathogenicity and Reproduction of Pratylenchus agilis in Field Microplots of Soybeans, Corn, Tomato, or Corn-Soybean Cropping Systems. R. V. Rebois, Nematologist, Nematology Laboratory, Plant Protection Institute, USDA, ARS, NER, Beltsville, MD 20705. A. Morgan Golden, Nematologist, Nematology Laboratory, Plant Protection Institute, USDA, ARS, NER, Beltsville, MD 20705. Plant Dis. 69:927-929. Accepted for publication 6 March 1985. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1985. DOI: 10.1094/PD-69-927.

Pratylenchus agilis-infested microplots were established in a fumigated field. Three-year cropping rotations of continuous corn, soybeans, or tomatoes; alternate corn and soybeans; 2 yr of soybeans followed by corn; or 2 yr of corn followed by soybeans were used to evaluate their effects on P. agilis populations and crop yields. Crops were rated according to their host suitability for increasing nematode populations as follows: I.O. Chief (corn) > Marglobe (tomato) > Williams (soybean) > Essex (soybean). Essex was a poor host, and continuous cropping to soybeans did not result in yield losses. Continuous cropping to corn and tomatoes, or 2 yr in corn followed by soybeans, resulted in crop damage in the third year. In excised root tissue cultures, P. agilis is capable of ectoparasitic as well as endoparasitic feeding. Possible plant-parasitic relationships between P. agilis, P. scribneri, and P. hexincisus are discussed.

Keyword(s): feeding behavior, lesion nematodes.