VIEW ARTICLE

Resistance Reactions of Castor and Guar to Root-Knot Nematodes. Calvin C. Orr, Nematologist, U. S. Department of Agriculture, Texas A&M University Agricultural Research and Extension Center at Lubbock, Lubbock, Texas 79401; E. D. Morey, Southern Region and Laboratory Technician, Texas A&M University Agricultural Research and Extension Center at Lubbock, Lubbock, Texas 79401. Phytopathology 64:1533-1536. Accepted for publication 16 July 1974. DOI: 10.1094/Phyto-64-1533.

Cotton root-knot nematodes, Meloidogyne incognita acrita, in naturally infested cotton-field soil, invaded the roots of guar and castor, but development was slow, or females failed to mature and reproduce. Guar roots produced a hypersensitive reaction, and giant cells were poorly formed. Castor roots were readily invaded by root-knot larvae; however, the larvae either migrated out of the root or failed to develop.