1S19] DISEASES OF PLANTS. 655 



copper sulphate and formaldehyde were found to be quite efficient in the control 

 of oat smut. A study of the watermelon disease indicates that there are several 

 strains of Fusarium that cause wilt, and that the disease is favored by certain 

 types of soil. 



Damage from soil fungi, F. J. Seaver {Jotir. N. Y. Bot. Gard., 18 (1917), 

 No. 212, pp. 186-188). — The considerable damage noted among various plants in 

 the New York Botanical Garden during the season of 1917 is attributed to the 

 fungi which normally inhabit the humus of the soil. Funkias, the foliage of 

 which had been partly killed, showed no leaf fungus in sufficient abundance to 

 account for the injury, but a Sclerotium in the soil appeared to have attacked 

 these plants as well as others, causing considerable damage. Tulips failed to 

 bloom and appeared to be suffering from the presence on the bulb of S. tulipce, 

 which possibly also originated In the soil. Rootstocks of the wild geranium 

 were Injured by another fungus which has been brought under investigation. 



[Botany and phytopathology, Canada], T. A. Crerar (Rpt. Min. Agr. 

 Canada, 1918, pp. 48-50). — Forestry investigations have demonstrated the pres- 

 ence, over such wide areas, of white pine blister rust on its secondary host, 

 currant or gooseberry, that it is feared that the control of the disease within 

 the area of general Infection will not be possible. Work has been carried on 

 relative to the hibernation of the fungus on currants, longevity of the spores, 

 distance of their transportation by winds, and other phases of the disease look- 

 ing to its control. 



Increased attention has been paid to the control of plant diseases generally. 

 Losses from grain rusts were not severe during the year. Apparently a means 

 has been worked out for controlling peach canker, which now causes much loss. 

 Studies are reported in connection with potato diseases, leaf roll, club root, apple 

 scab, and grain diseases. 



Plant diseases [in Ireland] (Dept. Agr. and Tech. Instr. Ireland, Ann. Gen. 

 Rpt., 18 (1911-18), p. 60). — A new disease of potato has been studied and has 

 received the name " foot rot." It is said to be due to a new species of 

 Phytophthora in the soil allied to that producing pink rot, also that producing 

 potato blight. 



The Colletotrlchum causing a disease of flax seedlings has been shown to 

 hibernate in the skin of the eed, infecting the plant while very young. A seed 

 treatment has been worked out which has not yet received practical application 

 In seed tests. 



A list of diseases of economic plants occurring in the Bombay Presidency, 

 H. M. Chibber (Dept. Agr. Bombay Bui. 65 (1914), pp. 27).— This list of dis- 

 eases Is arranged according to host plants. An index is given, together with a 

 classified list of the 71 genera of fimgus parasites in connection with the host 

 plants. The author records also, 1 bacterium, 1 alga, 5 flowering plants, 2 

 nematodes, 1 woolly mite (Phytoptus sp.), and some diseases due to unknown 

 causes. 



Foot and stalk disease of wheat, E. Foex (Compt. Rend. Acad. Agr. France, 

 5 (1919), No. IS, pp. 543-548). — A distinction is drawn between the lateral 

 wheat stalk disease caused by Leptosphmia herpotrichoides and the more 

 basal, frequently subterranean, and usually encircling attack due to Ophiobolus 

 graminis. The results of observations during several years are outlined as 

 regards the relations to disease of such factors as fertilizers, seeding time, and 

 crop succession. 



The black stem rust and the barberry, E. C. Stakman (U. S. Dept. Agr. 

 Yearbook 1918, pp. 15-100, pis. 10, fig. 1). — A popular account is given of the 

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