DISEASES OF PLANTS. 273 



Agr. Prat, n. ser., 7 (1904), No. 21, pp. 678, 679) .—The author recommends the addi- 

 tion of sublimed sulphur to Bordeaux mixture when spraying grapevines, the 

 addition of the sulphur being for the purpose of preventing the occurrence of the 

 powdery mildew. 



It is recommended that to the ordinary solution of copper sulphate should be 

 added 2.5 kg. of sublimed sulphur thoroughly mixed with the amount of lime neces- 

 sary to make 100 liters of Bordeaux mixture. Instead of this preparation a second 

 is suggested, the addition of miscible sulphur, which consists of sublimed sulphur, 

 70 per cent; carbonate of soda, 20 per cent, and powdered resin, 10 per cent. This 

 can be readily added to a copper solution at the rate of 2.5 kg. per 100 liters. 



The use of verdigris for the control of downy mildew, E. Chuard and F. 

 Porchet (Chron. Agr. Canton Vaud, 17 (1904), No. 12, pp. 351, 352).— In reply to 

 numerous inquiries regarding the use of neutral acetate of copper at the viticultural 

 station, the authors give a brief account of the use of this fungicide, comparing it with 

 Bordeaux mixture. 



The verdigris solution used was a 1 per cent solution, and 2 equal plats of grape- 

 vines received a spraying of the neutral verdigris and Bordeaux mixture on the same 

 day. Ten days later, heavy rains having fallen, an examination was made of each 

 treated plat, and it was found that the verdigris solution was more adherent than the 

 Bordeaux mixture. One objection to the use of this solution is that there are no 

 evident traces of its having been applied to the vines. In order to correct this, 

 numerous attempts have been made to add neutral substances, such as white clay, 

 kaolin, and carbonate of magnesia, to show where the fungicide had been sprayed. 

 As yet none of these have proved entirely satisfactory. 



Simultaneous treatment for preventing attacks of the grape-fruit worm 

 and the downy mildew, G. Martin (Rev. ViL, 21 (1904), Nos. 531, pp. 177-180; 

 532, pp. 222-225; 533, pp. 241-243). — The use of a combined fungicide and insecti- 

 cide for preventing attacks of the grape-fruit worm and the downy mildew is recom- 

 mended. Directions are given for the preparation and application of a mixture 

 which consists of resin 15 kg., caustic soda 2 kg., verdigris 1 kg., ammonia 10 liters, 

 and water 100 liters. This solution has been successfully used by the author in 

 spraying nearly 800,000 vines. 



Grape phthiriosis, L. Mangin and P. Viala (Rev. ViL, 21 (1904), Nos. 532, pp. 

 205-210; 533, pp. 237-241, figs. 8). — In continuation of the previous report on this dis- 

 ease of grapes due to symbiosis between Daclylopius vitis and Bornelina corium 

 (E. S. R., 15, p. 165), the authors add a number of facts to the biology of the insect 

 and its symbiotic fungus. 



A note on the gray rot of grapes in Algeria, L. Trabut (Rev. Vit., 21 (1904), 

 No. 544, PP- 563, 564, fig. 1). — Attention is called to the fructification of Botrytis cinerea 

 on various portions of grapevines and particularly to the lesions caused by the fungus 

 on the petioles and adjacent portions of the vines. 



The chlorosis of fruit trees and its treatment, J. Lochot (Rev. Hort. [Paris], 

 76 (1904), No. 10, pp. 236, 237).— The use of sulphate of iron for the prevention of 

 chlorosis is commented upon, this chemical being used not only to water about the 

 roots, but also as a spray to the leaves. When used in too strong a solution, it fre- 

 quently injures the foliage to a very considerable extent. 



The author describes a treatment which consists of thoroughly spraying the trees 

 late in autumn with a concentrated solution of copper sulphate. This treatment has 

 been successfully applied in a number of instances, and it is further recommended 

 for the horizontal branches of the trees that, cutting through the bark at intervals of 

 about a foot, will aid in admitting the iron salt to the tree and obtain more rapid 

 results. Another method mentioned is that of boring small holes into the affected 

 trees and putting from 4 to 12 gm. of sulphate of iron into the tree trunk. 



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