48 EXPERIMENT STATION RECORD. [Vol.40 



sporium sacchari was very restricted in extent this year, generally following 

 attack by M. sacchari or other injury. 



Tobacco showed the presence of wilt due to attack by bacteria just above the 

 ground, also a disease which withers and kills the plants and which is sup- 

 posedly caused by a Fusarium. A case of blossom-end rot of tomatoes was 

 examined. Mango leaves were injured by an alga, supposedly a Cephaleuros. 

 and mango branches and trunks showed what is thought to be another species 

 of alga. 



Mycology and plant pathology, J. Macke.nna (Rpt. Prog. Agr. India. 1916-17. 

 pp. 64-72). — It is now known that Tylenchus anguxtus, the cause of ufra dis- 

 ease, though not able to reach the tender portions of the rice plant when the air 

 is dry, is able to do so when the point of saturation of the air with moisture is 

 approached. Nematodes retain their vitality in dry air for eight months, in 

 moist air for four months, and in water for one or two months. They do not 

 reproduce in water or dry air. 



Tokras (Orobanche sp.) were not controlled by the use of sodium nitrate. 

 Striga lutea, a pest of millet which germinates only in the presence of a host, 

 can be counteracted in large part by the method of trap crops. Striga appears 

 to be controllable in cast- of EU usine coraoana by employment of early-maturing 

 varieties. Rhizoctonia on jute appears to be greatly favored by deficiency of 

 potash. Cotton root rot appears to be due to some soil deficiency of a chemical 

 nature. Peanut was heavily attacked by tikka disease, supposedly due to 

 deficiency <>f phosphates. 



Bud rot of palmyra palms has been reduced considerably by systematic ob- 

 servations and other operations. Koleroga disease of areca palm is being suc- 

 cessfully controlled by spraying, and the anaberoga disease, caused by I'omes 

 luciiins, is being successfully combated by eradication, liming, and trenching. 

 Root disease of coconut palm, though still important, has been checked. 



Rubber black thread disease is said to be cau>-ed by a fungUS which is a wound 

 parasite and which develops only in moist conditions. A serious root disease of 

 tea has been identified as Ro-scllinia Uotlirinn. SphwrottUbe sp. was found on 

 living tea roots in stiff acid soils. A sickly growth of tea bushes was thought to 

 be due to Nectria cancri. An outbreak of blister blight ( ICxobasidium vetcans) 

 was investigated. 



A coffee root disease < /■'. auxtralis) was studied. Black rot and leaf disease 

 of coffee were controlled with Bordeaux mixture. Spike disease of sandal has 

 been shown to be infectious, although it may be influenced by external factors. 

 A similar or identical disease attacks a number of wild plants in southern 

 India. 



Scab of potatoes (Spongospora subterranea) is reported from Bombay Presi- 

 dency. Experiments in the treatment of peach leaf curl with Burgundy mix- 

 ture and lime-sulphur are in progress. Other diseases under investigation at 

 Pusa are sal tree disease, anthracnose of chilies and legumes, and sclerotial 

 diseases of sugar cane and rice. 



Operations against [plant] disease, G. A. D. Stuart (Rpt. Dept. Ayr. 

 Madras, 1916-17, pp. 13, 14). — The system of examination ami treatment for 

 protection against palmyra disease is said to have reduced greatly the percent- 

 age of infection in spite of conditions most favorable to the disease. Favorable 

 results are reported of the spray treatment for mahali disease of areca nuts. 

 Copper sulphate solution as a seed treatment was found to be effective against 

 smut in case of Italian millet, Guinea corn. etc. 



Corticiums causing Pellicularia disease of the coffee plant, hypochnose of 

 pomaceous fruits, and Rhizoctonia disease, F. A. l'.rui i \>m. Hittouri Bot. 

 Oard., ■'> [1918), \" -'. pp. n:> tS2, figs. 5).— This is an account of study by 



