346 EXPERIMENT STATION RECORD. 



one generation of spores, and Its adaptation to climatic conditions in tlie ele- 

 vated regions where it is usually found. 



Report on the wintering' over of rust fungi in the uredo stage, E. Baudy§ 

 (Ann. Mt/col., 11 (1913), No. 1, pp. 80-43, figs. 3). — Continuing work previously 

 noted (E. S. R., 28, p. 345), the author found that Puccinia dispersa on rye 

 survived the winter of 1911-12 (the minimum temperatures being somewhat 

 lower than those of the previous winter, both mycelium and uredospores show- 

 ing early capacity for reproductive activity. A bibUography is appended. 



Influence of " pickling " on the germination of cereals, J. C. Johnson 

 (Jeur. Bd. Agr. [London], 20 {1913), No. 2, pp. 120-12^) .—A series of experi- 

 ments conducted at the University College, Cork, is described, in which an 

 attempt was made to determine the action of formaldehyde and copper sulphate 

 solutions on the germination of wheat, barley, and oats. Various strengths of 

 solutions and tinaes of application were tested, the formaldehyde varying from 

 0.06 to 2 per cent solutions and the copper sulphate from 0.25 to 5 per cent solu- 

 tions, and the times of application for the different lots ranging from 5 minute^ 

 to 3 days. 



On comparing the two series of experiments it was found that formaldehyde 

 affected germination adversely according to its concentration. The more marked 

 depression in germination was due to copper sulphate. Grains treated with cop- 

 per sulphate took about twice as long to germinate as those treated with formal- 

 dehyde. Of the formaldehyde solutions, 0.125 per cent seemed the best for 

 practical purposes, as it did not diminish germination appreciably after 15 

 minutes' immersion of the seed and proved to be a good fungicidal strength. 



Anthracnose of sisal hemp, F. J. F. Shaw (Agr. Jour. India, 8 {1913), No. 1, 

 pp. 65-68, pis. 3; abs. in Agr. News [Barbados], 12 {1913), No. 289, p. 174).— 

 A description is given of a disease of agaves due to Colletotrichum agaves. 



Inoculation experiments showed that the disease in question was due to the 

 above fungus, but that it was necessary to injure the surface of the leaf in 

 order to secure infection. This seems to indic-ate that the fungus is a woiuid 

 parasite. As the leaves frequently crack during periods of hot dry weather, 

 it is thought that infection by the fungus would be facilitated in this manner. 

 Collecting and burning the diseased leaves and spraying with Bordeaux mixture 

 are recommended for checking the disease. 



Hop mildew, F. M. Blodgett {New York Cornell Sta. Bui. 328. pp. 281-310, 

 figs. 19). — The resufts are presented of a study of the hop mildew, due to 

 Sphwrotheca hmnuli, in which the economic importance of the disease, life his- 

 tory of the fungus causing it, and methods of control are described. 



Among the observations reported, attention is called to the early infection of 

 the lower leaves from the winter fruit bodies and the subsequent infection of 

 the younger growing parts of the hop plant, particularly the flowering catkins. 

 The fungus causing this disease can not be distinguished by any morphological 

 characters from that causing mildew on a large number of weeds, but cross- 

 inoculation experiments showed that the fungus is highly specialized, the strain 

 attacking hops being confined to that plant and to the Japanese hop and entirely 

 unable to attack other plants. 



For the control of the mildew proper sanitation in the hop yards is said to be 

 essential. Beginning in 1910 experiments with fungicides were conducted and 

 confined mostly to the use of sulphur, as liquid sprays were considered imprac- 

 ticable. In 1911 the use of sulphur and sulphur and lime was compared, with 

 the result that 61.2 per cent of the hops were free from mildew where sulphur 

 alone was applied and 12.3 per cent where sulphur and lime was used, while 

 in the check all hops were more or less infected. In 1912 comparisons were 

 made between flowers of suphur, such as is generally used, and " flour sulphur," 



