SORGHUM SMUTS AXD VARIETAL RESISTANCE 51 
(10) Among the miscellaneous sorghums some have proved to be very sus- 
ceptible, such as the hybrid broomcorns and Schrock sorghum. Freed sorghum 
and husserita have shown a somewhat lower percentage of infection. Others 
have shown a high degree of resistance, such as darso, Dwarf hegari, and Sudan corn. 
The observations at Amarillo indicate that the sorghums are less 
susceptible to Sorosporium reilianum than to Sphacelotheca sorghi. 
Feterita, milo, and broorncorn have shown no infection. The kafirsand 
kaoliangs were only slightly infected. The following varieties of sor- 
ghum showed marked susceptibility : Brown durra (S. P. I. No. 17537) ; 
White durra (S. P. I. No. 17535) , Black Amber sorgo (S. P. I. No. 32384) , 
Minnesota Amber sorgo (F.C.I. No. 01950),Red Amber sorgo (S.P.I. Nos. 
1534 and 17548), Colmansorgo, Early Rose sorgo, and Schrock sorghum. 
By removing the plumule sheath from germinating seeds and 
inoculating them with spores of SpJiacelotheca sorghi it was possible 
to secure heads of feterita infected with kernel smut. This method 
was not successful with milo. 
There appears to be no correlation between the rate of germination 
of sorghums and their susceptibility to infection with covered kernel 
smut {SpJiacelotheca sorghi (Link) Clinton). 
Environmental conditions play an important part in the percent- 
age of infection with covered kernel smut. The results in 1918 at 
Columbia, Mo., were markedly lower than those obtained in previous 
years. These low percentages of infection perhaps may be correlated 
with the high temperature and low precipitation preceding and fol- 
lowing the planting of the grain. No such marked differences in the 
percentage of smut infection were observed at the Manhattan station, 
where the environmental conditions were not strikingly different 
during the various planting seasons. 
BIBLIOGRAPHY 
(1) Ball, Carleton R. 
1906. Saccharine sorghums for forage. U. S. Dept. Agr., Farmers' Bui. 
246, 37 p., 7 fig. 
(2) 1910. Three much-misrepresented sorghums. U. S. Dept. Agr., Bur. 
Plant Indus. Circ. 50, 14 p., 2 fig. 
(3) 1910. The history and distribution of sorghum. U. S. Dept. Agr., Bur. 
Plant Indus. Bui. 175, 63 p., 17 fig. Bibliography, p. 51-53. 
(4) 1911. The importance and improvement of the grain sorghums. U. S. 
Dept. Agr., Bur. Plant Indus. Bui. 203, 45 p., 13 fig. 
(5) 1913. The kaoliangs: A new group of grain sorghums. U. S. Dept. 
Agr., Bur. Plant Indus. Bui. 253, 64 p., 15 fig., 2 pi. 
(6) and Rothgeb, Benton E. 
1913. Kafir as a grain crop. U. S. Dept. Agr., Farmers' Bui. 552, 19 
p., 8 fig. 
(7) 1918. Grain-sorghum experiments in the Panhandle of Texas. U. S. 
Dept. Agr. Bui. 698, 91 p., 13 fig. 
(8) Barber, C. A. 
1904. Diseases of Andropogon sorghum in the Madras Presidency. 
Dept. Land Records and Agr., Madras, Agr. Branch Bui., v. 
2, no. 49, p. 273-288. 
(9) Beeson, M. A., and Daane, Adrian. 
1919. Darso. Okla. Agr. Exp. Sta. Bui. 127, 19 p., 6 fig. 
(10) Brefeld, Oscar. 
1883. Die Brandpilze I. Ustilago cruenta Ktihn and Ustilago reiliana 
Kuhn. In his Untersuchungen aus dem Gesammtgebiete der 
Mykologie, Heft 5, p. 91-95. 
(11) 1895. Die Brandpilze II. Infectionen mit Hirsebrandconidien auf Sor- 
ghum saccharatum. In his Untersuchungen aus dem 
Gesammtgebiete der Mykologie, Heft 11, p. 43-51. 
