AND COLLEGE, PUSA, FOR 1915-16 51 



arborescens is a normal parasite present in almost every 

 poppy field and probably, like most of its tribe, only epide- 

 mic under favourable climatic conditions for its spread, 

 Rhizoctonia develops chiefly in fields in which the drain- 

 age is defective. The Economic Botanist, United Pro- 

 vinces, has discovered certain varieties which appear to be 

 almost immune to Peronospora and in the growth of these 

 and improved cultivation and drainage lies the best hope 

 of preventing loss of the crop. 



(5) Rhizoctonia on jute and sugarcane. Samples of 

 jute seed from Dacca were found to contain the sclerotia 

 of Rhizoctonia Solani Kiihn adhering to the seed. The 

 parasitism of this fungus upon jute has been the subject of 

 a previous publication but up to the present R. Solani has 

 been a source of damage in the region of the " collar " and 

 has not been known to infect seed. It is not clear how this 

 comes about and the matter will receive further investiga- 

 tion. 



Specimens of sugarcane received from the Central Pro- 

 vinces were found to be infected with a sclerotial fungus. 

 The fungus was obtained in pure culture and strongly 

 resembled Rhizoctonia destruens Tass. ; moreover inocu- 

 lations upon Delphinium (the original host of R. destruens) 

 and upon betle vine were successful. Further infections 

 upon sugarcane resulted in the death of the outer leaves 

 and of the young shoots at the base of the plant; the infec- 

 tions are still progressing at the moment of writing. In 

 the field the fungus causes a bright red spot on the leaf 

 sheath and this is the first noticeable result in artificial 

 infections. In badly diseased specimens the leaf bases are 

 dark red and have a fibrous appearance as if the paren- 

 chyma had been rotted away leaving the vascular bundles. 

 On stripping the leaf bases the stem has a pale pink colour 

 under the epidermis and in section the interior shows a 

 generally diffused salmon pink colour partly obscured by a 

 thick white felt of hyphse. The mycelium shows a ten- 

 dency to form strands of hyphae in a manner suggestive of 

 R. destruens. "Further research is in progress. 



