134 



Notes on the Occurrence of Sclerotinia Fructigena. 



Fraxk D. Kern. 



The rotting of tl*e peach and phiui I'ruit at the beginning of the ripening 

 period is a ratlier familiar occui'rence. Soft, broN\'n spots appear, which 

 usually- grow until the whole fruit hecomes rotten and tinally shrivels up, 

 becoming numunilied. Twigs, leaves and flowers may also be attacked and 

 exhibit discolored areas. 



The rot is caused by a fungus, doubtless best known as MoniUa fructi- 

 gene, a name given it by Persoon' in ISOl. That it was simply the couidial 

 form of some ascomycetous species, was strongly suspected by several inves- 

 tigators and Schroeter- was even confident enough to transfer it to the 

 genus Sclerotinia in 1803. This, however, remained a mere assumption 

 until iy02, when Norton' collected the apothecia at several localities in 

 Maryland, and established, by means of cultures, their relation to the coui- 

 dial form. 



Although the perfect stage had been diligently searched for before 

 this was the first time it had ever been rej)orted. Because this form has 

 been so rarely seen, and because of the economic importance of the fungus 

 in the other phase of its life history, it was with unusual delight and inter- 

 est that the apothecia were discovered in the spring of 1906 in Indiana. 

 Two collections were made, both at Lafayette, and by Prof. J. C. Arthur, 

 on buried peaches, under trees in his garden, April 21 ; another by Dr. B. 

 W. Olive and the writer, on buried plums, in a trash heap on a vacant lot, 

 May 8. The earlier collection was in perfect condition, while the latter 

 was somewhat dried. Both discharged clouds of spores when first dis- 

 turbed, and when .iarred even after partial drying made several subse- 

 quent discharges. 



Only the mummied fruits which were buried or partially covered bore 

 ajwthecia. On the plums one to three or four arose from a single fruit, 

 while on the peaches as high as thirty or forty appeared about the sides of 



' Persoon, Syn. Fung., 693. 1801. 



^ Schroeter, Krypt. Fl. Schles, 3'':67, 1893. 



= J. B. S. Norton, Iron?. Acad. Sci., Sb. Louis, 12:91-97, pis. 18-21. 1902. 



