Sclerotinia fructigena. 95 



some cases, with moist and warm air, 2 cm. or more from the 

 origimil spore. After a few day's growth, most of these 

 mycelia sent up branching hyphae into the air in a circle a 

 short distance from the center. These bore in chains the 

 characteristic yellowish-gray conidia of Monilia fructigena. 

 After further growth, other rings of clusters of conidiophores 

 were produced beyond the first, their production apparently 

 depending on moisture conditions. 



It remained to test inoculations of fruit and tiowers with 

 the ascospores or conidia developed from them. Some of the 

 fresh apothecia were placed in contact with peach flowers 

 moistened and inclosed in paper sacks and some on mutilated 

 buds. Probably owing to dry weather no results were obtained. 

 With cut twigs of blooming peach and plum at the same time 

 placed under sterile jars indoors and similarly treated, in two 

 or three days the peculiar browning of the petals seen in the 

 Monilia blossom-blight appeared, followed by tufts of conidia. 

 Although a great deal of blight appeared in the check cultures 

 from Monilia spores already on the peach buds, several spots 

 started in such places as to indicate undoubted infection from 

 the ascospores. Finally, after a few weeks all the flowers 

 blighted and became covered with dense masses of white 

 hyphae often hanging down 2-3 cm. Although this may be 

 some other mold, it appears to be connected with the Sclero- 

 tinia. 



On May 12, peach petals collected the day before in Garrett 

 Co., Md., were placed in a sterile Petri dish. On some were 

 placed sterilized drops of water, others were touched by wet, 

 fresh apotheca, and others with Monilia conidia from the 

 peach flowers mentioned above. In 3 days those inoculated 

 were blighted, turned brown, and later developed clusters of 

 conidia.- Those simply wet remained perfectly fresh and white, 

 3 weeks later. 



I find a very good way to study the development from the 

 ascospores is to cut very thin sections of the dry apothecia 

 and place them in water or some nutrient liquid where the 

 germination of the spores actually in the asci can be watched 

 and thus the spores cannot be confused with those of other 

 fungi that might be present. With such sections placed on a 



