IOWA ACADEMY OP SCIENCE 
101 
FUTURE INVESTIGATIONS. 
It was my purpose when I first commenced a study of this disease in 1909 
to be able to obtain the complete life history, before publishing any account. 
But as the disease is of comparative recent origin in the United States and 
Canada, and as the disease in the places reported is more destructive than 
has been recorded for either Germany or Denmark, it was thought best to give 
forth the results of my observations and investigations to serve the purpose, 
possibly, of assisting in keeping this disease, and similar allied ones, in check, 
CONCLUSIONS AND SUMMARY. 
1. Helminthosporium teres Sacc., known in Europe since 1881, was first 
discovered in the United States in 1907 at Ames, Iowa, but w^as not destructive 
enough to cause appreciable loss until the season of 1909. 
2. Helminthosporium teres Sace., occurs upon the barlej^ alone and cannot 
grow on any other host. 
3. Helminthosporium teres Sacc., causes greatest destruction through the 
formation of its conidia. Further than this, pycnidiospores and sclerotia have 
been developed culturally. In all probability perithecia, with asci and asco- 
spores develop from the sclerotia. 
4. Inoculation experiments verify the fact that the disease is largely trans- 
mitted by the seed. 
5. Temperature and moisture play an important part in the development of 
the disease. Seed should be sown when the temperature is sufficient for entire 
germination but low enough to retard the growth of the fungus. 
6. Disease can be best checked by treating seed with formaldehyde. Soil 
sanitation methods are important factors in following out remedical measures. 
BIBLIOGRAPHY. 
la. Beckwith, T. D. Root and Culm Infections of Wheat by Soil Fungi in North 
Dakota. Phytopathology. 1:169. 
1. Bolley, H. L. Conservation of the Purity of Soils in Cereal Cropping. Address 
before the Fifth International Dry Farming Congress at Spokane, Wash. Oct. 6, 
1910. 
2. Briosi & Cavara. I Funghi Parasiti Delle Piante Coltivate Od. Utile. No. 81. 
.8 .Diedicke, H. Uber Den Zusamenhang Zwischen Pleospora und Helminthosporium 
Arten Centralblatt fur Bakt. und Parasitenkunde II Abt : 9:52-59. 9 f. 
4. Hecke, L. Die Braunfleckigkeit Oder Blaltbraune der Gerste. Wiener Land- 
wirthschaftliche Zeitung. 48 :435, 1898. 
5. Hollrung, M. Die Verhutung des Brandes insbesondere bei Gerste und Hafer 
durch die S'aatkornbeize. Landwirtschaftliche Jahrsbucher 26:145. 
6. Johnson, T. Econ. Proc. Roy. Dublin Soc. 1 ;345. 1907. 
7. Nback, Fritz. Helminthosporium gramineum Rabh. und Pleospora trichostoma. 
Wint. Zeitschr fur Pflanzenkh. 15 :193, 1905. 
8. Pammel, L. H. Breeders’ Gazette. July 28, 1909. 
9. Pammel, L. H., King, Charlotte M., Bakke, A. L. Two Barley Blights. Bull. Iowa 
Agr. Exp. Sta. 116: 178-190, pi I-.',. 
10. Pammel, Weems & Scribner. Yellow Leaf Disease of Barley. Bull. la. Geol. Sur- 
vey. 1:209. 
11. Potter, M. C. Observations on a Disease Producing the “Deaf Ear” of the Bar- 
ley. Univ. of Durham Philosophical Society Proceedings. 3 :2. 
12. Ravn, F. Kolpin. Nogle Helminthosporium Arten. Botanisk Tidskrift. 23:101-320, 
1900, pi. 2, f. 26. 
13. . Ueber einige Helminthosporium Arten und die von denselben 
hervorgerufenen Krankheiten bei Gerste und Hafer. Zeitschr. fur Pflanzenkrank- 
heiten. 11:1-26, 1900. f. 8. 
Saccardo, P. A. Sylloge Fungorum. 4 :402 ; 10 :610 ; 14 :1062 :1084. 
14 . 
