.. 23 

 Relation to light 

 It has been noted that the strojnata of germinating ergot are 

 positively phototropic and negatively geotropic, and that the inten :.Vj 

 sity of the strona coloring varies directly with the intensity of light 

 within ordinary limits. 



The first inoculation v/ith aspospores of C.. -pur'aure a was 



done "by IDurien (280) Tulasne nade inoculations with C.. purpurea . C.. 



microcephala 

 nigricans . andjC. roaxgETseiiphaia . using "both ascospores and conidia. Euhn 



repeated the es;periinents of Tulasne v/ith £. -purpurea , following the 

 classical experiments of Tulasne iiaany other workers have been able to pro- 

 duce the disease by artificial inoculation with both ascospores and conidia. 

 Stager in his study has made a large number of successful inoculations, from 

 which he was able to establish some new species and certain specialized 

 races. He also showed the host range of each, 



LIEB HISTORY OP CIAVICEPS PUEPTBEA. nffiEIATIOH 



TO 

 PATHOC-EKBSIS 

 Seasonal develoyanentBof the diseas e. 

 The ascospores described in a prededing chapter are produced in 

 great numbers, as we shall see later, and are carried in various ways to 

 the flowers of the susceptible plant. \Vhen moisture and ternperature con- 

 ditions are fayorable, they germinate vdthin 24 hours. At the beginning 

 of the germination, the spores swell and with the progress of germination 

 light spots appear throughout their length, followed by a widening at 

 certain points. 



