Occurrence of Sweetpotato Chlorotic Leaf Distortion (Fusarium lateritium) in North Carolina. J. B. Ristaino, Department of Plant Pathology, North Carolina State University, Raleigh 27695-7616. C. W. Averre, G. Abad, and W. R. Jester. Department of Plant Pathology, North Carolina State University, Raleigh 27695-7616, and Agricultural Extension Service, Box 757, Kinston, NC 28501. Plant Dis. 75:750. Accepted for publication 26 February 1991. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-0750.
Chlorotic leaf distortion of sweetpotato (Ipomoea batatas (L.) Lam.)
was observed in midseason in 1987 in fields of sweetpotato cv. Jewel
in North Carolina. During 1988-1990, the symptoms were seen in
many cv. Jewel fields in 10 counties. Symptoms included stunting
of vines, purple vine terminals, delayed leaf unfolding, deformation
of young leaves with raised veins, and interveinal chlorosis on mature
leaves. Most mature leaves recovered from symptoms. A white "waxy"
substance concentrated on or near the leaf margins and diffused over
the adaxial leaf surface consisted of mycelia, macroconidia, and microconidia
of Fusarium lateritium Nees:Fr. The pathogen was repeatedly
isolated from surface-disinfested apical buds, petioles, leaves, and stems
but not from storage or fibrous roots. F. lateritium was also isolated
from cvs. Beauregard, Southern Delite, Regal, and Excel and was
observed in foundation, certified, and registered planting material.
Isolates were sent to the departments of plant pathology at Louisiana
State University and The Pennsylvania State University for confirmation
of identity. These observations are consistent with those of Clark
et al (1) and confirm the occurrence of F. lateritium in sweetpotato
fields in North Carolina.