398 PATHOLOGY [Bot. Absts. 



bean. Eight Manchurean beans were also found susceptible. No mosaic developed in any 

 plots of variety Robust. The following varieties and related species are immune or highly 

 resistant to mosaic: Dolichos lablab, hyacinth; Cicer arielinum Garbanzo; Vigna sinensis, 

 black-eye; P. aconitifolius, moth bean; P. aureus, Mung bean; Canavali ensiformis, Jack bean. 

 These may be used for breeding resistant varieties. — R. E. Vaughan. 



2736. Reimer, F. C. A new and effective disinfectant for pear blight. Better Fruit 

 13 10 : 24-27. Apr., 1919. [Also published in: Monthly Bull. State Comm. Hortic. (Cali- 

 fornia) 7: 562-565. 1918. (See Bot. Absts. 2, Entry 535.)] 



2737. Reinkixg, Otto. Philippine plant diseases. Phytopath. 9: 114-140. 1919.— The 

 author has made a survey of fungous diseases on the island of Luzon (Philippine Islands). 

 Climatic conditions are especially favorable for the development of fungous pests and the 

 native farmers are ignorant of control measures. The coffee industry has been entirely 

 wiped out by a disease; coconut, rice, sugar, and citrus industries are also hampered and the 

 culture of all vegetables complicated by various diseases. The estimated loss averages about 

 10 per cent for all crops.— A list of 48 of the principal cultivated and wild hosts of the Launa 

 Province. Luzon, is given, together with the relative importance of the crop and the names 

 of the diseases which are destructive to them. A short description of each disease is given, 

 together with the name of the causal organism. Many of these organisms have never been 

 described, but the more common hosts are attacked by those parasites which are prevalent 

 upon them in other countries. The citrus trees are attacked by canker (Bacterium citri), 

 die-back, and gummosis, coconuts suffer most from bud rot (cause not determined), leaf 

 spots, and sooty mold, while the most destructive coffee disease is rust (Hemileia vastatrix). 

 On the tomatoes are found bacterial wilt (Bacillus solanacerum) , late blight (Phytophthora 

 itifestans) and damping off (Pythium de baryanum). — Bacterial diseases seem particularly 

 severe, especially bacterial wilt of potato, egg plant and tomato and bacterial blight of beans. 

 — Maude Miller. 



2738. Rhoads, Arthur S. The biology of Polyporus pargamenus Fries. New York 

 State Coll. Forestry Tech. Publ. 11. 197 p., 31 pi., 6 fig. 1918— See Bot. Absts. 3, Entry 

 2497. 



2739. Rodda, T. E. Brown rot experiment at Arataki. Jour. Agric. [New Zealand] 

 16: 222-228. 1918. — Spraying experiment, fractional in part, but also designed to test rela- 

 tive value of a number of fungicides. Some trees sprayed four times showed a higher per- 

 centage of rot than the unsprayed ones. "The weight of evidence is in favor of the sulfur 

 compounds." — Similar trials on apricots showed that Bordeaux mixture gave the best con- 

 trol of rot but because of discoloration of fruit should give way to lime-sulfur solution 1 : 130. 

 — Rust was controlled satisfactorily by all the fungicides used.— D. Reddick. 



2740. Rodda, T. E. Control of red mite and black-spot. New Zealand Jour. Agric. 

 18: 344-347. PI. 1. 1919.— Oil, 1 : 30, used when buds were in advanced pink stage was very 

 effective against red mite. Bordeaux, 6: 4: 50, was much better than lime-sulphur solution 

 for the control of black spot, Venturia inaequalis, but caused considerable fruit russeting 

 and is therefore not recommended. Oil was used on the same trees as the Bordeaux. — 

 N.J. Giddings. 



2741. Rose, D. II. Blister canker of apple trees: a physiological and chemical study. 

 Bot. Gaz. 67: 105-146. Feb., 1919.— See Bot. Absts. 4, Entry 1546. 



2742. Rosin, II. It. A bacterial root-rot of field corn. Arkansas Agric. Exp. Sta. Bull. 

 162. 12 p. 4 pi, Aug., 1919. — The author describes a serious root-rot disease of field corn, 

 considered identical with that studied by Burrill in Illinois in 18S9. A bacterium was iso- 

 lated from the diseased tissues, inoculated on healthy plants and reisolated from the dis- 

 eased roots resulting. It is noted that the organism produces lesions on sorghum identical 

 with those produced by the sorghum organism, Bacillus sorghi. The organism is not de- 

 scribed further than to note that it is motile by one polar flagellum. — John A. Elliott. 



