title: Scanning Electron Microscopy of Second-Stage Juvenile Cephalic Morphology in Heterodera glycines Races.
abstract: Scanning electron microscopy (SEM) was used to compare juvenile cephalic morphology of the five described races of Heterodera glycines. Races 1, 2, 3, and 4 were obtained in the United States and race 5 was obtained from Japan. Differences in the gross morphology o f labial discs; ventral, dorsal and lateral lips; amphidial apertures; and fissures on the labial disc o f some specimens were observed. There was considerable interracial and intraracial variation which precluded separation o f juveniles of H. glycines races by SEM.
authors.forename: G R
authors.initials: GR
authors.lastname: Noel
authors.forename: B A
authors.initials: BA
authors.lastname: Stanger