308 BULLETIN No. 189 [June, 



Sweden. Eriksson 37 ' 39 observed a disease of carrot and beet in 

 1898 in Sweden, caused by R. Crocorum. He was able to inoculate 

 this fungus on garden and sugar beet,^ alfalfa, potato, and many weeds 

 Stellaria media, Myostis arvensis,' Galeopsis, Titrahit, Erysimum 

 clieiranthoides, Urtica dioica, and Sonchus sp. In addition to these 

 hosts Eriksson has reported R. Solani (Corticium vagum) on potato 

 and R. Crocorum on turnip and kohl-rabi. 



DISTRIBUTION OF RHIZOCTONIA IN INDIA AND 

 AUSTRALIA 



Shaw, 109 working on the morphology and parasitism of Rhizoctonia 

 in India, reported RJiizoctonia Solani on peanut (Arachis Jiypogoea), 

 cowpea (Vigna catjang), jute (Corchorus capsularis), Dolichos Lab- 

 lab, Trichosanthes cucumernia, soybean (Glycine soja), mulberry 

 (Morus alba), sesame, melon roots, cotton, roots of Agave rigida, and 

 potato. 



In Australia, McAlpine 67 found R. Solani very widely distributed 

 on potato. 



PLAN OF PROCEDURE 



The main object of the present research was to determine whether 

 of the culturable forms of Rhizoctonia one or more than one race or 

 species. is present in this country. The work was taken up from the 

 following standpoints : 



1. Symptoms of Khizoctonia disease on various hosts 



2. InocuJation experiments 



3. Growth on media 



4. Measurement of mycelial cells 



5. Soil survey 



SYMPTOMS OF RHIZOCTONIA DISEASE ON VARIOUS 



HOSTS 



Following are presented the observations of the writer concerning 

 the nature of the diseases caused by Rhizoctonia on the various hosts, 

 together with the principal facts which appear in literature regarding 

 Rhizoctonia on the more important crop plants in this country. 



ALFALFA, Medicago sativa 



On March 17, 1914, the attention of the author was called to the 

 damping-off of young alfalfa seedlings in the agronomy greenhouse 

 of the Station. Microscopic examination and pure cultures showed it 

 to be due to Rhizoctonia. The seeds had been sown in rows in pure 

 quartz sand and kept well moistened. The young seedlings, on ger- 

 mination, were somewhat crowded, so that the conditions were very 



