No. 1, July, 1920] PATHOLOCV 189 



became infected with the Phoma sp. within a few days, bu1 uninjured plants only after Mine 

 weeks. Spraying with Bordeaux mixture is recommended as a control measure. — E. M. 

 Doidge. 



1245. BOTJLGBB, G. S. [Rev. of: Rankin, \V. II. Manual of tree diseases. Macmillan 

 Co. : New York, 1919. xx+898 p., 70 fig.] Jour. Botany 57: 166-167. 1919. 



1246. Bhandbs, E. W. Banana wilt. Phytopath. 9: 339-390. tS pi, S fig. L919.— In 

 any given region the wilt affects most severely the variety of banana most widely planted there. 

 The range of this disease coincides in general with that of tin' cultivated banana. Sudden, 

 vivid yellowing of the outer or lower leaf blades and petioles, decided dwarfing of the entire 

 plant, and longitudinal splitting of the outer leaf bases are all symptoms ofthedi .rough; 

 on by varying conditions. The disease changes the color of the stelarl issue of the rhizome. 

 A careful description of sporodochia, conidia, mycelium and cultural characterist ics of Fusar- 

 iuin cubense is given, and methods of isolation are described. Temperature, moisture, light, 

 and oxygen supply relations were determined experimentally. Banana wilt is probably the 

 results of toxic excretions by the fungus, Fusarium cubense, which has been shown to be the 

 cause of the disease. Inoculum consists of macroconidia and microconidia. Dissemination 

 is mostly carried on by air currents, water, mud, and infected leaves used for protecting bunches 

 packed in cars for shipment. Infection courts are two in number, the wound on the rhizome 

 where the sucker is cut off, and the side of the bulb where a root is given off. Penetration is 

 by means of a germ tube. Growth is intracellular. The severity as well as the spread of ban- 

 ana wilt is strikingly correlated with certain well defined weather conditions. Arid regions 

 where irrigation is necessary are entirely free from banana wilt. Exclusion, eradication, and 

 immunization are suggested as control measures. — R. G. Bitterman. 



1247. Brandes, E. W. The mosaic disease of sugar cane and other grasses. U. S. Dept. 

 Agric. Bull. 829. 26 p., 1 pi. (colored), fig. 1-5. 1919.— The mosaic disease of sugar cane 

 is similar to that commonly found on the tomato, potato, bean, tobacco and cucumber and is 

 defined as an "infectious chlorosis." Although common in cane fields of Argentine, Java, 

 Cuba, and the Hawaiian Islands for some time, mosaic appeared in Porto Rico about 1916 

 and has since spread to three-fourths of the fields of this Island. Losses incurred have range s 

 as high as nearly 50 per cent decrease in tonnage. Survey of the cane areas of the Gulf States 

 of the United States show several limited areas of infection in Louisiana, Mississippi, Georgia 

 and Florida. — Characteristic symptoms of mottling and striping are described as present in 

 the leaves. In more advanced stages there is a tendency toward dwarfing and yellowing of 

 the plant though the plant is seldom actually killed. Injuries similar to mosaic but induced 

 by environmental, fungous and bacterial agencies are also described. — More than a thousand 

 varieties including all the leading commercial ones in the United States are susceptible. 

 Nearly all varieties of Cuba and Hawaiian Islands are susceptible. Many Japanese varieties,, 

 notably Kavangire and Cayuna 10 are entirely immune. Corn, sorghum, rice, millet, crab- 

 grass, foxtail and Panicum have proved to be hosts to mosaic of the same identity. The wild 

 grasses commonly associated with cane seem to be immune. The disease is due to some 

 virus or inoculum and not to such previously suggested causes as worn out soils, climatic con- 

 ditions, "run-out" varieties and bud variations. Infectiousness of mosaic is probably due to 

 insect carriers and the incubation period ranges from two to three weeks. Infection is not 

 thought to be by simple contact of plants. — Commonly transmitted through the planting of 

 diseased seed pieces and no indication that contagion persists in the soil. Seed disinfection 

 with Bordeaux mixture or corrosive sublimate has not been effective. Fertilizers and lim- 

 ing also not effective. Control measures which have proved efficient and which are now 

 advocated are: selection of healthy seed plants, use of clean seed and resistant varieties, in- 

 spection of and rogueing of diseased plants from slightly infected fields, exclusion of infected 

 seed stock from healthy cane areas and the eradication of the disease in areas of recent 

 infection. — E. V. Hardenburg. 



