Blue Lupine as a Host for Colletotrichum trifolii from Alfalfa and for C. fragariae from Strawberry. Ronald E. Welty, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture, Oxford Tobacco Station, Forage Research Unit, Oxford, NC 27565, and Professor of Plant Pathology, North Carolina Agricultural Research Service, Raleigh 27650. Plant Dis. 68:142-144. Accepted for publication 17 August 1983. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-142.

Seedlings of blue lupine (Lupinus angustifolius) were inoculated in the greenhouse with race 1 or 2 of Colletotrichum trifolii or with one of three isolates of C. fragariae from North Carolina, Louisiana, or Florida. In a disease severity index (DSI) of 1–5, blue lupine was highly susceptible to race 1 or 2 of C. trifolii (DSI 4.3 and 4.9, respectively) and the three isolates of C. fragariae (DSI 4.5–4.9). Alfalfa (Medicago sativa) cultivars Saranac AR and Arc were also inoculated with the five isolates of Colletotrichum. The DSI of Saranac AR and Arc inoculated with C. fragariae ranged from 1.1 to 1.8. Saranac AR was resistant to races 1 and 2 of C. trifolii (DSI 2.3 and 3.4, respectively). Arc was resistant to race 1 (DSI 2.4) and susceptible to race 2 (DSI 4.9) of C. trifolii. The host range of C. trifolii and C. fragariae was extended to include blue lupine.