MAINE APPLE DISEASES. 365 



Altcrnaria decay. A decay of apples caused by a species of 

 Altcrnaria was first described from Colorado by Longyear.* 

 This fungus entered the apple at the blossom end and prothiced 

 a cob-webby growth of mycelium around the seeds. An Altcr- 

 naria has been found a number of times associated with apple 

 decays in Maine. This fungus usually occurs on injured places 

 such as the blossom end injured by insects or broken places in 

 the skin. Associated with other fungi this Altcrnaria forms a 

 rather thick, dry covering of mycelium over the injured place. 

 The fungus does not usually penetrate very deeply in such cases 

 but when ripe apples are inoculated from pure cultures, it is 

 found to be capable of causing a complete decay. This fungus 

 alone has been reisolated a number of times from decaying ap- 

 ples which had been inoculated, thus proving that it caused the 

 decay. The apple decay Altcrnaria differs sufficiently from a 

 species of the same genus which has been found repeatedly on 

 dead spots in apple leaves and on dead parts of other plants so 

 that the two fungi can be distinguished readily in culture. The 

 Altcrnaria from apple leaves has not been found to cause decay 

 of the fruit upon inoculation. 



Botrytis decay. A species of Dotrytis causes a part of the 

 decay of apples in Maine. It has been found causing a rot of 

 early apples on the tree and inoculations have shown that it not 

 only attacks ripe fruit but that it is capable of causing a rot of 

 green apples. The fungus spread, rather rapidly in the tissues 

 of winter apples which were inoculated early in August so that 

 in 2 weeks one-half of each apple was decayed. It causes a 

 rapid and complete decay of ripe apples. 



Phonia decay. This rot is caused by Phoma inali Sclmlz & 

 Sacc, which is able to attack both wood and fruit. A more ex- 

 tended account of this fungus is given in Bulletin 170 of this 

 Station. It causes only a slight decay of green apples but when 

 ripe apples are inoculated the rot spreads almost as rapidly as in 

 the case of some of the well known apple destroying fungi. 

 When the fruit is thoroughly invaded the pycnidia break out on 

 the surface giving somewhat the same appearance as in the case 

 of black rot but there is usually considerable mycelium on the 

 surface of the apple and this is white in color. The appearance 

 of an apple 34 days after inoculation with Phoma mali from a 



* Longyear, B. O. Col. Exp. Sta. Bui. 105, 1905. 



