1919] DISEASES OF PLANTS. 155 



the author has carried on inoculation experiments witli about 240 varieties and 

 species of bean and related plants to test their susceptibility to strains of 

 C. Undemuthianum , the presence of which was previously reported (B. S. R., 

 26, p. 747). Several species of Phaseolus and also species of other genera were 

 found to be affected with the anthracnose to some extent, but they were not 

 favorable host plants for the parasite. Some varieties of beans were found 

 susceptible to one strain of the fungus and others to a second. Resistance was 

 found in many distantly related plants. The degree of susceptibility of the 

 different varieties is indicated. 



Varieties of beans susceptible to mosaic, D. Reddick and V. B. Stewart 

 {Phytopathology, 8 (1918), No. 10, pp. 530-SSJt) .— During the progress of a 

 study of the mosaic diseases of beans, the authors tested the susceptibility to 

 this disease of a number of the more common varieties of Phaseolus vulgaris. 

 About 30 varieties showed unmistakable symptoms of mosaic as a result of inoc- 

 ulation, while others which did not develop mosaic as a result of a single test 

 are under further observation. 



A storage fermentation of dasheens, O.. T. Wilson {Phytopathology, 8 

 (1918), No. 10, pp. 547-549, fig. 1). — From a study of a peculiar rotting of dash- 

 eens in storage, the author has found that it is due to yeasts. These under 

 some conditions secure access to the tissues of the corms and tubers and cause 

 a fermentation of the sugars, rendering the affected parts useless for food. 



Bamularia root rots of ginseng, O. L. Zinssmeistee {Phytopathology, 8 

 {1918), No. 11, pp. 557-571, figs. 8). — A description is given of a disease of the 

 roots of American ginseng popularly known as rust. The roots are said to 

 show dark brown, dry lesions, at first small and scattered but finally becoming 

 widespread and deep-seated. Two types of injury are recognized. In the first, 

 the injury is merely superficial and is confined to a few layers of cells immedi- 

 ately beneath the epidermis. In the second, the lesion extends through the 

 cortex, frequently involving the stele, and in many cases the rot extends 

 throughout the entire cross section of the root. The disease is said to be 

 widely distributed, and it is expected that it will be found in almost all ginseng 

 regions. 



A study of the cause of the disease revealed the presence of two species of 

 Ramularia, to which the names R. destruotanis and R. panacieola n. spp. are 

 given. The cultural characteristics and morphology of the organisms are de- 

 scribed, and technical descriptions of both species are included. 



Diseases of parsnips, A. D. Cotton {Roy. Bat. Gard. Kew, Bui. Misc. Inform., 

 No. 1 {1919), pp. 8-21, pis. 2, figs. 2). — Recent study of the disease of parsnips 

 known as canker, which does much damage in certain localities or situations 

 (the degree of injury being affected apparently by conditions and varieties), 

 has shown that the trouble is due primarily to physiological phenomena in- 

 volving rupture not followed by renewal of the surface tissue, and not directly 

 to invasion by fungi, although these organisms are afterwards involved. The 

 contributory conditions are discussed. Preventive measures include rectifi- 

 cation of certain cultural practices and the use of potash and salt to retard 

 maturation. Other parsnip diseases are discussed. 



Diseases of parsnips, A. D. Cotton {Jour. Bd. Agr. [Londoni, 25 {1918), No. 

 1, pp. 61-71, pis. 2). — This reproduces most of the report noted above on 

 parsnip canker, omitting notes of other diseases mentioned in that article. 



Potato leaf roll: Its diagnosis and cause, E. J. Wortley {Phytopathology, 

 8 {1918), No. 10, pp. 507-529, figs. 16).— After an account of the losses due to 

 leaf roll of potatoes in Bermuda, the author gives the diagnosis of leaf roll 

 and presents the various theories regarding its cause. 



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