850 EXPERIMENT STATION RECORD. 



(luciiij; tli(> Iniiiiidity. Wlicii possilde the branclies tliat an» badly affected should 

 be cut olT and. if tliis is done late in the season, burned in order to i)revent the 

 frerniination of the telentospores. 



Yellow stripe in daffodils, II. K. Daulington (.Jour. h'ni/. Iloit. .S'or. | Lo/i- 

 don], S'l (WOH), No. 2, pp. 161-166). — While daffodils are usually considered as 

 exceptionally free from disease, the author calls attention to what is apparently 

 a jihysiolosical disturbance which results in considerable injury to the plants. 



This trouble, which is called yellow strii)e, shows itself in a mild case as a 

 scarcely perceptible discoloration or yellowing of the veins of the leaves, but in 

 more seridus cases distinct bands of yellow may be seen running lenji;thwise of 

 the leaves. In bad cases no flowers at all will be produce<l, and the leaves 

 wither before they are fully developed. Except in bad cases the yellow stripOs 

 seldom run the full length of the leaf. 



The trouble is quite distinct from the yellowing of the leaf which takes place 

 during the summer after the maturity of the bulb. The author believes that 

 it is not a specific disease, but is a consequence of unsuitable conditions of soil, 

 or inclenieiit weather at the critical stage in the growth of the plant. 



Parasitic rose canker, H. T. GtJssow (Jour. Roi/. llort. ^oc. [Lotidoii], .1'/ 

 (IHOS), No. 2, pp. 222-230. fiys. '/). — A new disease of roses is described, which 

 is said to be spreading in certain parts of (ireat Brit^tiin. 



The disease apparently starts in the one-year-old wood, and is not noticed 

 until far advanced. One of its principal characteristics is shown in the deep 

 fissures covered with an abnormal growth, which have the appearance of canker 

 spots. The bark bursts and the wound does not heal normally, but the callus 

 continues to grow until badly cankered spots result. The author believes that 

 the disease is identical with that described by Sorauer (E. S. R., 18, ]). 114.3), 

 in which case the disease was attributed to fi'ost injury. 



A study of material showed there was present a fungus that is believed to be 

 Identical with that described by Kock (E. S. R., 17, p. (ill), but the author 

 thinks that the species does not differ from the common ('onlotlnjriiiiii fiickclii, 

 and he considers the latter fungus to be the cause of the rose canker described. 



Notes are also given on a blackberry canker due to C. turmefaciens n. sp. 

 This fungus causes the development of excrescences on the stems from the size 

 of a pea to that of a walnut, or even larger. A technical description of the 

 fungus is given. 



A new lilac leaf disease in England, H. T. GiJssow {(lard. Cliroii., ,?. ser., 

 U (I'JOS), No. 11J,6, pp. .'lOJ,, -',05, figs. 2).— A description is given of a leaf 

 disease of lilac due to Pseudomonas syringce. The aft'ected leaves are greatly 

 disfigured and the injury appears suddenly and seems to spread rapidly. In 

 an early study of the disease a fungus was quite commonly observed, and the 

 injury was believed to be due to Cladosporium licrharum. Subsequent studies, 

 however, showed that the fungus is of secondary importance and that the pri- 

 mary trouble is due to bacteria. The organisms have been isolated, cultivated 

 in various media, and successful inoculation exi)eriments conducted, resulting 

 in the i)roduction of typical forms of the disease. The organism is apparently 

 that describetl by van Hall (E. S. R., 13, p. 1019), and it has also been shown 

 to be capable of infecting a number of other plants, among them the apple, 

 sour cherry, buckwheat, Atriplex horiensis, black poplar, etc. 



On account of the nature of the disease, the author states that spraying 

 would be futile against its spread, but that a careful lookout should be kept 

 for spots upon the foliage and all diseased shoots cnt out and burned. 



