INOCULATION EXPERIMENTS. 81 



COTTON TO COTTON. 



On March 19 five flowers were inoculated by applying conidia in 

 sterile water from a cotton boll to the stigmas. All the bolls soon 

 turned black and nearly all dropped off. One boll that remained on 

 the plant about two weeks before it died became half covered with 

 acervuli. 



On June 24 six young bolls were inoculated by puncture with 

 conidia from a cotton boll. In about two weeks small, dark, sunken 

 spots had formed on all and four showed acervuli. 



COTTON TO PUMPKIN. 



On November 2 a pumpkin was inoculated by puncture with conidia 

 from a pure culture of the cotton fungus. No signs of infection ever 

 appeared. 



COTTON TO HUBBARD SQUASH. 



A squash was inoculated by puncture with conidia from a pure 

 culture. No signs of infection ever appeared. 



COTTON TO WATERMELON. 



On November 2 a watermelon was inoculated by puncture with 

 conidia from a pure culture from cotton. No rot followed, but a 

 slight development of hyphae and a few acervuli formed at the punc- 

 ture. Spore-bearing setas were present in these acervuli, as is usually 

 the case with Glomerella gossypii. 



CRANBERRY TO APPLE. 



On April 27 six sound apples were inoculated by puncture with 

 conidia from a pure culture. No rot or acervuli had developed at the 

 end of a month. Later inoculations produced a slight decay in one 

 instance and a few acervuli formed. 



CRANBERRY TO SWEET PEA. 



On April 6 stems and young leaves of young plants in the green- 

 house were inoculated with ascospores in sterile water applied to the 

 surface. No signs of infection ever appeared. 



CURCULIGO TO COTTON. 



On April 2 three flowers in greenhouse were inoculated by applying 

 conidia in sterile water to the stigmas . No signs of infection appeared, 

 but the young bolls dropped off. They were placed in a moist cham- 

 ber, but no acervuli developed. 

 46023°— Bui. 252—13 6 



