Oct. 1,1920 Fusarium-B light (Scab) of Wheat and Other Cereals 21 



EXPERIMENTAL RESULTS 



Isolations. — In the vicinity of Madison, Wis., where the writer secured 

 most of his material, Gibber ella saubinetii is the most common and most 

 important cause of the headblight of the cereals, and the writer believes 

 this to be true throughout the country. The following Fusarium species 

 were also isolated from blighted heads and other parts of the cereal plants : 

 Fusarium avenaceum, 10 times — 4 times from wheat heads from a field 

 near Madison and 6 times from a single sample of 10 blighted spelt heads 

 from Hawthorne, which is located in the extreme northwestern part of 

 Wisconsin; F. herbarum, 8 times — 3 times from blighted wheat heads 

 from a lodged wheat field near Madison, Wis., and 5 times from corn 

 stalks; F. culmorum, once from a blighted wheat head from Arlington, 

 Va. ; F. culmorum var. leteius, twice from blighted wheat heads from a 

 lodged wheat field near Madison, Wis.; F. arcuosporum, 10 times — once 

 from a blighted oat seedling and c) times from barley heads left in the 

 field late in the fall and cornstalks early in the spring; F. scirpi, four 

 times from blighted wheat heads from a lodged wheat field and once from 

 a blighted wheat head from one of the Experiment Station plots at Madi- 

 son, Wis., which was badly overgrown with weeds; F. solani, once from a 

 grown wheat plant showing footrot; F. arihrosporioidcs, 5 times — once 

 from a blighted wheat head from a lodged wheat field and 4 times from 

 blighted barley heads; F. redolens, 3 times — once from a discolored rye 

 stem near a node, once from a blighted wheat head from Knoxville, Tenn., 

 and the third time from a blighted barley head from a weed-overgrown 

 plot in the Experiment Station field, Madison, Wis. 



On the other hand, Gibber ella saubinetii was identified by the writer on 

 over 2,000 blighted wheat, barley, rye, oat, and spelt heads from various 

 parts of the following States: Wisconsin, Illinois, Minnesota, Indiana, 

 Maryland, Kentucky, Ohio, Virginia, West Virginia, South Carolina, 

 Georgia, Alabama, North Dakota, and Michigan. This shows that, from 

 the standpoint of headblight of the cereal crops, G. saubinetii is the most 

 important organism. 



All species of Fusarium given here, including Gibberella saubinetii, were 

 isolated originally by poured-plate dilution of conidia from distinctly 

 blighted wheat heads. During the course of the work, however, some of 

 these species were often isolated from blighted rye, barley, and oat heads, 

 or stems, and from sheath, shank, root, and node rots of corn, or in a few 

 cases from other hosts. The organisms attacking the cereal crops above 

 the ground produce numerous conidia over the infected area. The conidia 

 so produced are often normal and uniform in size and shape, and the 

 trained student will not only have no difficulty in separating the various 

 species before he has grown them under artificial conditions but he will 

 be able also to determine in a general way the various species, at least 

 the various sections to which they belong. 



