1018] DISEASES OF PLANTS. 453 



with sour sap are couimonly saprophytes which are favored by conditions un- 

 favorabie to healtliy growOi, no conclusive evidence of parasitism having yet 

 been obtained. Tlie remedy suggested is removal of the predisposing condi- 

 tions, particularly that of excessive soil water, though other factors also re- 

 quire attention. 



An undescribed bark canker of apple and the associated organism, G. H. 

 Coons {Rpt. Mich. Acad. ScL, 17 {1015), pp. 117-122, pi. /).— Owing to delay 

 in the publication of this report, the new combination (Plenodotnus fuscomacu- 

 lans) here proposed has already appeared in other communications by the 

 auttior (E. S. R., 34, p. C47; 35, p. 658). The canker is here described, and 

 the morphology and classification of the organism are discussed. 



A blossom wilt and canker of apple txees, H. Wokmald {Ann. Appl. Biol., 3 

 {1917), No. Jf, pp. 159-204, Pl^- 5)- — Having carried forward the work previously 

 reported by Salmon (E. S. R., 32, p. 148) on brown rot canker of apple, said 

 to be increasing in intensity and destructiveness year by year in the southeast 

 of England and attacking many, perhaps all, of the local varieties, the author 

 gives the results of a comparison of the blossom wilt fungxis with other Monilias 

 of fruit trees, with the results of inoculation tests and of other studies. 



Infection takes place through the open llowers, invading the spur and some- 

 times resulting in a branch canker. These dead portions produce pustules dur- 

 ing the winter and spring, conidia from which infect the blossoms and cause 

 the wilt. After shedding the conidia the canker becomes callused, and the 

 lesion eventually heals. Inoculation of apple blossoms with pure cultures re- 

 sulted in the death of the inflorescences and spurs and in some cases in cankers, 

 conidia-bearing pustules appearing on the parts during the following winter. 



The causal organism is said to be easily distinguished from M. fructigena 

 and is provisionally referred to M. cincrea, but it is said to show on culture 

 media a different habit from the fungus bearing that name in America. 



Removal of all infected spurs before the blooms open checks the disease, as 

 does also spraying so as to prevent the conidial pustules from shedding their 

 conidia during the period of blooming. 



The blossom wilt and canker disease of apple trees, H. Wobmald {Jour. 

 Bd. Agr. {London], 24 {1917), No. 5, pp. 504-513, pis. 4).— The information given 

 in the article noted above from another source is here briefly presented, with 

 some advice to fruit growers. 



The gnarly apple disease of 1914, W. H. Venable {Vcrtnont Sta. Bui. 203 

 {1917), pp. 12, 13). — A description is given of a serious trouble of apples in 

 1914 in Vermont and New York, in which the fruit was misshapen, depressed, 

 and indented, the flesh below being a mass of brownish, corky tissue. No or- 

 ganism has been found in connection with this trouble, and it is believed to 

 have been due to late frost injury, a sharp frost having been reported during 

 a period when the trees were in full bloom. 



The effect of fungicide on the spore germination of Longyear's Alternaria, 

 R. W, Goss and S. P. Doolittle {Rpt. Mich. Acad. Sci., 17 {1915), pp. ISS- 

 187). — An organism, sometimes referred to as Longyear's Alternaria (B. S. R., 

 17, p. 780), has been shown to infect apples in widely scattered regions of the 

 United States, causing a core rot which appears to be more susceptible to the 

 influence of Bordeaux mixture than of any other preparation tested, though 

 several which are named gave a measure of control, and lead arsenate in- 

 creased the value of several. The author gives a brief account of varietal sus- 

 ceptibility, symptoms, microscopical characters, cultural characteristics, and 

 fungicidal tests. 



