INSTITUTE AND COLLEGE, PUSA, FOR 1911-12. 5fii 



of a Phytophthora which attacks castor, as part of a larger 

 investigation of the diseases of this crop. This species has 

 also been got into artificial culture. The simultaneous pro- 

 duction of the saprophytic habit by artificial culture in two 

 species of this genus, until recently supposed to be exclu- 

 sively parasitic, has permitted of important additions to 

 our knowledge of the biology of the genus. Phytofhthora 

 infestans, the cause of the well-known potato blight, was 

 found attacking potatoes and tomatoes at Jorhat in Assam ; 

 on a previous occasion, in 1902, it attacked potatoes in 

 Burdwan and Hooghly Districts in Bengal. Ordinarily 

 confined to temperate climates and always prevalent in the 

 Hill Tracts of India, it is, perhaps, to be feared that a race 

 is being developed which can withstand the heat of the 

 plains. 



{e) Sugar-cane diseases. — A memoir giving the results 

 of the work of the past few years has been commenced. The 

 difficulties encountered in carrying on field experiments, 

 owing to inability to control external conditions which 

 caused the partial loss of the crop on several occasions, have 

 led to much loss of time. A good deal of information has, 

 however, been obtained as regards methods of infection 

 other than by planting diseased cuttings, both in red-rot and 

 C eyhalosporium disease, and it is considered advisable not 

 to delay publication. This year's work includes these two 

 diseases and also smut. Early in 1912 specimens of a cane 

 disease which has appeared on the Jorhat Farm were 

 received from Mr. Meggitt, Agricultural Chemist, Eastern 

 Bengal and x\ssam, who laid stress on its resemblance to 

 sereh, the disease which has caused more damage in Java 

 than probably any other of the numerous diseases of this 

 crop. The resemblance is indeed striking and a recent 

 visit to Jorhat has not enabled me to identify the disease 

 with any of those known in India. The symptoms of sereh 

 are elusive, its cause is unknown, its treatment very trouble- 

 some; and the accurate identification of the Jorhat disease, 

 so that measures for its suppression may be taken if neces- 

 sary, is obviously a matter of the first importance. 



