Skip to main content
ARS Home » Pacific West Area » Wenatchee, Washington » Physiology and Pathology of Tree Fruits Research » Research » Publications at this Location » Publication #220001

Title: Alernaria undulata, a new species from Citrus sinensis

Author
item ROBERTS, RODNEY

Submitted to: Mycotaxon
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/27/2008
Publication Date: 6/2/2008
Citation: Roberts, R.G. 2008. Alernaria undulata, a new species from Citrus sinensis. Mycotaxon. 104:29-34.

Interpretive Summary: An unusual disease was observed on Australian citrus orange fruits in a retail display in a local grocery store. The disease occurred at the stem end, and caused the peel to shrivel and appear sunken. Gray, fuzzy growth of a fungus was associated with these lesions. Several members of the fungal genus Alternaria were isolated from these diseased fruits. One new species, A. undulata, was described from these strains based upon the wavy appearance of spore-bearing structures called conidiophores as seen during microscopic observation. Both the physical appearance and DNA fingerprint studies support the description of A. undulata as a new species.

Technical Abstract: A new species belonging to the Alternaria infectoria species-group, A undulata, is described from imported fruit of Citrus sinensis (navel Orange). A. undulata was associated with visible lesions that appeared to originate from the peduncular scars of several fruits purchased from a retail display in a local grocery store. The wavy appearance of primary and secondary conidiophores produced in potato-carrot agar cultures is the diagnostic character by which this species can be recognized. Cluster analyses of DNA fingerprint data sets support the inclusion of A. undulata in the A. infectoria species-group and its segregation from other members of this group.