DISEASES OF PLANTS. 245 



Cucumber wilt, J. Hanzawa {Ztschr. Pflauzenkraiik., 23 {1913), No. 2, pp. 

 65-12, pis. 2, figs. 3). — The author describes a wilt of cucumbers which recently 

 apiieared in a greenhouse at Sapporo, Japan. Among the fungi found in this 

 connection one was noted which was thought to be new and to cause the dis- 

 ease. This is described as Nectriella cucumeris n. sp. 



Onion smut, D. IIeduick {West. N. Y. Hort. Soc. Proc, 58 {1912), pp. 19 Jf- 

 197, fig. 1). — This disease {TJrocystis cepulw), attacking the leaves and bulb, 

 is said fo infect the onion when in the seedling stage, never after it is 3 in. 

 high. The exact method of infection is not yet certain. It is thought that the 

 very abundant spores may be carried on the seeds and may retain vitality in 

 the ground for 25 years, producing infection under favorable conditions of 

 heat and moisture; also that the hairlike tube resulting may branch and bear 

 secondary spores, increasing the possibilities of infection. 



Of the several methods of control proposed, rotation is not regarded as very 

 practical. Onions grown from sets and transplants are said not to be subject 

 to the disease. Treating the seeds with formalin is suggested, and a drip at- 

 tachment for the seed drill, sterilizing tlie soil in the immediate vicinity of the 

 seed by means of formalin, has been found helpful. Sulphur and air-slaked 

 lime, 100 lbs. and 50 lbs. per acre, respectively, used together, are recommended 

 as useful, if applied in drills with a special attachment, but not perfect as 

 regards control. Further experimentation is in progress. 



Disease of rice and of onions, R. Ramirez {Bol. Dir. Gen. Agr. [Mexico], 

 Rev. Agr., 2 {1912), No. 5, pp. 41 3-// 15, pis. 2). — A smut of rice ascribed to 

 Pleospora herharum and a spot disease of onions ascribed to Macrosporium 

 sarcimila are figured and briefly described. The author recommends in case 

 of the former, disinfection of the seed with formalin ; for the latter, applica- 

 tion of lime-sulphur solution in the strength of 1 : 1 : 100. 



A preliminary note on a new bacterial disease of Pisum sativum, Dorothy 

 M. Cayley {Proc. Roy. Soc. [London], Ser. B, 86 {1913), No. 586, pp. 171-173; 

 noted in Gard. Chron., 3. ser., 53 {1913), No. 1362, p. 7//).— The author gives 

 an account of studies on a serious disease affecting garden peas, killing a large 

 proportion of the crop in the neighborhood of Merton, Surrey. 



The disease is ascribed to a very large rod-shaped bacillus transmitted in 

 the interior of the seeds, which has been isolated from the stem of the living 

 l)lant and from the center of the cotyledons. The life history is said to be 

 complicated by involution forms and a zoogloeal stage. The biology and symp- 

 toms are discussed. In very bad cases little or no germination takes place. 

 It is thought that the bacillus passes up through the plant tissues, infecting the 

 young seed, those of a given pod all being diseased to an equal extent. This 

 disease is spread chiefly through the seed, but fresh infection may take place 

 through the soil. Results tend to show that the bacillus can penetrate only 

 very young tissue. 



It is said that in many respects the symptoms resemble those of streak dis- 

 ease of LatJiyrus odoratus. This disease has been claimed to be due to Thiela- 

 via basicola, but the author states that she has already found bacteria like those 

 here described in stems of diseased sweet peas. 



Further investigations ai'e in progress. 



Cystopus candidus on broad leaved pepperwort (Lepidium latifolium), B. 

 NoFFBAY {Jour. Agr. Prat., n. ser., 24 {1912), No. 31, pp. 147, 148; abs. in Inter- 

 nat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant Diseases, 3 {1912), 

 No. 10, p. 2306). — The author calls attention to the facts that L. laiifoUum, 

 occasionally found growing around dwellings in considerable abundance, is 

 attacked by C. candidus, and forms a source of infection by this fungus for 

 cultivated crucifers. 



