50 EXPERIMENT STATION RECORD. 



little damage. Smut (Vstilago sacchari) is under investigation, Sereh was 

 reported at Jorhat. 



An outbreak of fatal bud rot of coconut palms at Malabar, ascribed at first to 

 Pythium palmivorum, was finally assigned to the genus Phytophthora. A collar 

 rot of areca palms may be due to Fomes htcidus. 



Rhi::octonia napi, not previously observed in India, was noted on the Pusa 

 Farm, living chiefly on mustard, but being apparently almost omnivorous. R. 

 destruens (also noted on Delpliinium) caused a rot of potato, on which R. solani 

 was also common. A disease of poppy, associated with Rhizoctonia or with 

 Peronospora arborescens, is ascribed to lack of rotation as its chief cause. 



A cotton wilt of wide distribution was definitely shown to be a species distinct 

 from Fusarium vasinfectum, causing cotton wilt in the United States. It is also 

 less virulent, being unable to attack the Indian cotton known as •' buri," which 

 offers the only present hope of escape from loss by this fungus. 



A different and (in artificial inoculation) more virulent species of Fusarium 

 causes a wilt of sesame. No resistant variety is known, but the cold weather 

 crop is less subject to the disease than are the monsoon varletie.s. 



Potato blight {Phytophthora iiifestnns) does not survive the heat of the 

 plains, but may possibly become a serious pest in the hills. A Phytophthora, 

 discovered to attack Vinca and Petunia, is probably a variety of P. paraMtica, 

 which attacks castor beans. 



The perfect stage of Colletotrichum, causing anthracnose of the betel vine, 

 has been discovered to be an Ascomycetes, and the Colletotrichum and Glceospo- 

 rium on chili has been proved to be one and the same fungus. The disease 

 appears to be transmitted through the seeds. 



Introduction and acclimatization of new varieties of peanut has caused re- 

 cently a large degree of recovery in returns of this crop, which has been dimin- 

 ished by the tikka disease. 



The hot-water treatment proved useless against smut of Pearl millet. The 

 success of the formalin treatment was demonstrated on several estates. 



Tylenchus slmilis, the cause of a root disease of sugar cane and banana, 

 N. A. Cobb (V. .S. Dept. A</r., Jour. Ayr. Research. 4 (1915), No. 6, pp. 561-668, 

 figs. 2). — The author describes a disease of bananas which first made its ap- 

 pearance in Fiji in lS9t>-91, and which was attributed to the nematode T. simi- 

 lis. Then only the male nematodes were ob.served. In 1907 a disease of sugar 

 cane in Hawaii was investigated in which both sexes of the nematode were 

 recognized, and which at that time was described as T. hi for mis. Later 

 investigations have shown the same disease appearing on bananas in Jamaica. 



A critical study has proved that the two species are Identical, and a tefli- 

 nical description of the nematode is given. 



Plant diseases and pests {Bui. Dept. Agr. Trinidad and Tobago. 14 {1915), 

 No. 2, p. 62). — A statement by J. B. Rorer is quoted, noting good results from 

 l)roliniiii:iry sjirjiying oxperimonts with cacao, coconuts, ami cassava. 



Heat as protection ag'ainst insects and cryptogamic parasites of cultivated 

 plants, L. Skmichon {Compt. Rend. Aead. Sei. [Paris], 160 {1915), No. 17, pp. 

 569-571). — It Is claimed, as the result of tests, that water at temperatures of 

 55 to G5° will destroy not only Insect parasites mentioned and their eggs but 

 also fungus plant parasites which have either mycelium or reproductive bodies 

 exposed externally. Water at these temperatures also posses.ses considerable 

 spreading and adherent qualities, these statoments applying in cases of Oldlum 

 on grape or quince, rose mildew, Peronospora of grape, and Phytophthora of 

 potato and tomato. In the treatment of grape mildew It permits the reiluctlon 

 of the copper constituent as well as of the number of treatments. 



