Disease Note. A New Disease of Lentil Induced by Colletotrichum truncatum in Manitoba. R. A. A. Morrall, Department of Biology, University of Saskatchewan, Saskatoon, Canada S7N 0W0. . Plant Dis. 72:994. Accepted for publication 4 August 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0994D.
In 1986 and 1987, a disease of Lens culinaris Medik. caused by
Colletotrichum truncatum (Schw.) Andrus & Moore, the cause of
soybean anthracnose, was observed in Manitoba. White to grayish
spots developed on the leaflets and sometimes turned brown. Brown
lesions occurred on lower stems and pods of mature plants. Stem lesions
coalesced, causing general blighting, and acervuli were observed on
diseased stems. The disease sometimes occurred in foci where dead
stems with whitish sporulation of Fusarium spp. at the base suggested
an interaction with root rot. Surveys near Winnipeg in July 1987
showed that the disease occurred in 15 of 20 fields and on two different
cultivars. C. truncatum was isolated from seed harvested in three
heavily diseased crops, but never at a frequency above 2%. Inoculation
of seedlings with conidial suspensions showed that C. truncatum was
highly pathogenic on the lentil cultivar Eston; die back and lesions
similar to those in the field occurred. The pathogen was reisolated from
lesions. It is not known whether lentil isolates are pathogenic on
soybean, or vice versa, or whether significant losses occur on lentil in the
field. Few previous reports of Colletotrichum on lentil exist (1,2). |