THE OCCURRENCE OF FUSARIUM SPECIES IN CANADA: VI. TAXONOMY AND GEOGRAPHIC DISTRIBUTION OF FUSARIUM SPECIES ON PLANTS, INSECTS, AND FUNGI

Abstract

The present investigation was commenced in 1932 and has been continued annually since that time with the object of determining the identity, host range, and geographic distribution of the Fusarium species in Canada. Approximately 9000 isolates of Fusarium were studied. These isolates were obtained from 173 species and botanical varieties of plants, 14 species of insects, and 4 of fungi. Of the various species and botanical varieties of plants from which isolates were obtained, 19 were cereals and grasses, 19 were vegetable crops, 15 were fruit crops, 13 were field crops, 52 were ornamental plants, 31 were trees and shrubs, and 24 were common weed plants. Less than 1% of the total isolates was obtained from insects and fungi. Although most of the isolates originated in Manitoba, some were obtained from each of the other provinces of Canada except Newfoundland.A total of 18 species, 3 varieties, and 18 formae of Fusarium, classified in nine sections of the genus, were identified among the isolates from plants, insects, and fungi. These species, varieties, and formae are: F. chlamydosporum Wr. & Rg., F. poae (Pk.) Wr., F. sporotrichioides Sherb. (section Sporotrichiella); F. arthrosporioides Sherb., F. avenaceum (Fr.) Sacc. (Roseum); F. concolor Rg., F. semilectum Berk. & Rav. (Arthrosporiella); F. acuminatum (Ell. & Ev.) Wr., F. eauiseti (Cda.) Sacc. (Gibbosum); F. culmorum (W. G. Sm.) Sacc, F. graminearum Schwabe, F. heterosporum Nees emend. Raillo, F. sambucinum Fuckel, F. samb. var. coeruleum Wr., F. samb. f. 6 Wr. (Discolor); F. moniliforme Sheld., F. moniliforme var. subglutinans Wr. & Rg. (Liseola); F. lateritium Nees (Lateritium); F. oxysporum Schl. emend. S. & H., F. oxysporum var. redolens (Wr.) Gordon, F. oxysporum f. betae (Stewart) S. & H., f. callistephi (Beach) S. & H., f. cepae (Hanz.) S. & H., f. conglutinans (Wr.) S. & H., f. dianthi (Prill. & Del.) S. & H., f. fabae Yu & Fang, f. gladioli (Massey) S. & H., f. lilii Imle, f. lini (Bolley) S. & H., f. lycopersici (Sacc.) S. & H., f. melonis S. & H., f. narcissi S. & H., f. pini (Hartig) S. & H., f. tuberosi S. & H. (Elegans); F. solani (Mart.) App. & Wr. emend. S. & H., F. solani f. eumartii (Carp.) S. & H., f. phaseoli (Burk.) S. & H., f. pisi (Jones) S. & H., F. coeruleum (Lib.) Sacc. (Martiella).F. chlamydosporum, F. heterosporum, F. moniliforme var. subglutinans, as well as 14 formae of F. oxysporum and 3 formae of F. solani, are reported to occur in Canada for the first time in this series of papers.The six species isolated most commonly, as indicated by the number of hosts from which they were obtained, are F. oxysporum, F. acuminatum, F. solani, F. equiseti, F. avenaceum, and F. poae.The conidia and chlamydospores of F. chlamydosporum and F. heterosporum are illustrated by drawings.