1923] 



LEHMAN — POD AND STEM BLIGHT OF SOYBEAN 131 



were more conspicuously wrinkled and discolored than those 

 described under "a" above. Discolored areas were plainly 

 visible on the naked embryos which were disinfected by Norton 's 

 method and planted in agar plates. Each of the 5 seeds gave 

 rise to a rapidly spreading white growth, forming a colony which 

 was rather high, loose, and floccose to the very margin, but lower 

 and more dense toward the center. When mycelium from these 

 colonies was transferred to sterile soybean stems, pycnidia 

 developed in abundance, (c) The 5 seeds of this lot differed 

 from those described above in being entirely without seed-coat 

 wrinkling or discoloration. They were surface-sterilized by 

 Norton's method with seed-coats intact and then planted in 

 agar plates. Three of these seeds germinated and gave rise to 

 colonies which produced many fine large pycnidia when trans- 

 ferred to sterile soybean stems, (d) Five seeds appearing in 

 every way like those of lot c were put, without removing seed- 

 coats and without disinfection, into large test-tubes (20 X 2.5 

 cm.), in the bottom of which was moist blotting-paper. In the 

 case of one of the 3 which germinated, the fungus grew back 

 from the seed-coat or cotyledon upon the hypocotyl and there 

 formed pycnidia characteristic of D. Sojae. When killed by the 

 fungus the seedling had reached a height of less than 2 inches 

 compared with a height of 5-6 inches attained under such condi- 

 tions by healthy seedlings. 



7. Made January 22, 1921. Two lots of 5 seeds each were 

 shelled from a diseased plant which had been kept in the laboratory 

 since harvest. These seeds were plump and without surface 

 wrinkling or discoloration. One lot was disinfected and planted 

 in agar plates. Three of these seeds germinated and gave rise 

 to a fungous growth which, when transferred to sterile soybean 

 stems, produced a mycelium and pycnidia characteristic of D. 

 Sojae. The second lot of 5 seeds was put, without surface 

 sterilization, into large test-tubes provided with blotting-paper 

 moistened with Shive's 3-salt nutrient solution. Of the 3 seeds 

 which germinated, 2 were soon killed by a fungus whose identity 

 was not determined. The remaining seedling bore a cotyledon- 

 ary lesion. This lesion was cut out, sterilized in mercuric chloride 

 solution, and planted in an agar plate. This lesion gave rise to 



