THE BEAN BLIGHT: TRANSMISSION 299 



If the organism is generally carried on the seed, then seed 

 treatments are in order, and these should be made anyway, 

 until it is known that they are of no avail. In this connection 

 see Part I, page 69. 



Another important subject for field study is the discovery or 

 production of good resistant varieties. The subject is very 

 hopeful if the right persons take hold of it. 



Fig. 230*. — Agar plate of Bad. phaseoli showing a common form of colony- 

 referred to in the text. Organism isolated by Florence Hedges in 1917 from a 

 Maryland bean pod and used many times for successful inoculations. Plate 

 poured May 22, 1920, and photographed June 4. X 5. 



LITERATURE 



Beach: Bull. 48, N. S., N. Y. Agr. Exp. Sta. (Geneva) 1892. 



Smith: Proc. Am. Assoc. Adv. Sci., Vol. XLVI, 1897, pp. 288- 

 290. Species here named Bacillus phaseoli. 



Smith: Bull. 28, Div. Veg. Phys. and Path. U. S. Dept. of 

 Agric, 1901. 



Halsted: Bull. 151, N. J. Agr. Exp. Sta., 1901. 



Barlow: Bull. 136, Ontario Agr. Exp. Sta., 1904. 



Sackett: Bull. 138, Colorado Agr. Exp. Sta., 1909. 



Edgerton and Moreland : The bean bhght and preservation 

 and treatment of bean seed. La. Agr. Expt. Sta. Bull. 139, 

 Baton Rouge, La. 1913. 



Rapp : Aged bean seed, a control for bacterial blight of beans. 

 Science, n. s.. Vol. L, Dec. 19, 1919, p. 568. 



See also "Bacteria in Relation to Plant Diseases," Vol. I, 

 Fig. 62; Vol. II, Fig. 15 and pi. 17 (Fig. 3). 



