1919] DISEASES OF PLANTS. 51 



of plants closely related to the cotton plant. Wind-blown rain is considered 

 an important agent of dissemination, both local and general. Little evidence of 

 insect dissemination has been found. 



Sterilization of the seed coat by the use of sulphuric acid and bichlorid of 

 mercury has been found the most efficient means of control. 



Attack of peas in Gironde by Heterodera schaclitii, J. Captjs {Min. Agr. 

 [France}, Ann. Scrv. Epiphyties, 5 (1916-17), pp. 239-244). — The author notes 

 a severe outbreak of nematodes occuri'ing in Gironde during 1915, but not since 

 that time in sufficient severity to attract attention. The effects of the attack on 

 the plants are described. The plants also showed the presence of a fungus, the 

 characters of which are said to correspond closely to those of Fusarium vasin- 

 fectum, pisi, considered as the conidial form of Ncocosmospora vasinfecta. The 

 fungus usually attacked the plants near the base of the stem, the nematodes 

 attacking the roots, which showed the presence in large numbers of the brown 

 cysts, which are simply the bodies of the females distended with eggs. The 

 fungus is thought to be unable to attack vigorous plants. 



Common potato diseases and their control, A. V. Osmun (Agi: of Mass., 

 1911, pt. 2, pp. 125-133, figs. S). — This is a discussion of early blight (Macro- 

 sponum solani), late blight {PhytopliUiora infestans), scurf or Rhizoctonia, 

 scab, blackleg, and dry rot and wilt, with precautionary and other preventive 

 measures, including sprays. 



Studies on potato leaf roll, E. Blanchard and O. Ferret {Min. Agr. [France'\, 

 Ann. Serv. Epiphyties, 5 (1916-17), pp. 245-252, pi. 1). — This is a more extended 

 account than that previously noted (E. S. R., 40, p. 347) of potato leaf roll, 

 which is said to exist in various degrees of severity in different areas indicated. 



Potato spraying experiments in 1917, M. T. Cook (New Jersey Stas. Rpt. 

 1917, pp. 561-563). — A brief account is given of potato spraying experiments 

 carried on in cooperation with some growers, in which Bordeaux mixture, Kil- 

 Tone, and arsenate of lead were used as fungicides, some plats being sprayed 

 with a combination of Bordeaux and arsenate of lead. 



The highest yield in one instance was obtained where the plats received a 

 spray of arsenate of lead, but the average of the plats receiving Bordeaux 

 mixture and arsenate of lead was several bushels higher than that of the plats 

 receiving no Bordeaux. On another farm the highest yield was obtained where 

 Kil-Tone was used, the lowest yield being from the plat which had been sprayed 

 with the combination of Bordeaux and arsenate of lead. 



The author considers that not very much dependence can be placed in these 

 results, as the crop was exceptionally free from disease in the early part of the 

 season and the growth was unusually good. 



Smuts of jowar (sorghum) in the Bombay Presidency. G. S. Kulkarni 

 (Agr. Research Inst. Pusa Bui. 78 (191S), pp. 26, pis. 6).— This report embodies 

 the results of observations, which are still in progress, made by the author 

 during 5 years in the Bombay Presidency on the smuts of jowar. 



This name applies to all cultivated varieties of Andropogon sorghum, which 

 occupies third place as regards acreage among cultivated crops of this region. 

 The smuts, which are the most important among the fungus diseases of 

 sorghums, are classed as loose, long, whole-head, and grain smuts, each of 

 which is described. Experiments are cited to prove that infection with seed- 

 borne spores occurs only in case of loose and grain smuts, and that copper 

 sxilpliate checks the disease in both cases. Soil infection is apparently absent 

 in case of these smuts, spores of which, however, may retain vitality from 2 

 to 6^ years under suitalile conditions of dryness. Whole-head smut seems to 

 attack chiefly by way of the soil and is not checked by seed treatment. Long 



