SPOTTINGS IN PLANTATION RUBBER DUE TO FUNGI. 



By A. SHARPLES, A.R.C.S., D.I.C. 



Assistant Mycologist, Department of Agriculture, 

 Federated Malay States. 



SPOTTINGS or discolorations in plantation rubber have 

 been attributed to many causes since the beginning of 

 the plantation industry. It was obvious from the first 

 that micro-organisms were the cause of certain types of 

 spots, and various suggestions were made as to the 

 causal organisms. Ridley suggested that Protococcus 

 mvalis, an alga responsible for "red snow" in Europe, 

 might be the cause of the red spots. Brooks later 

 reported from Sarawak that he obtained Bacillus pro- 

 digiosus from crimson spots on crepe rubber. The 

 moulds, which develop so readily on the surface of badly 

 dried rubber, were recognized from the first, but were 

 not considered responsible for any of the internal 

 growths. 



About the year 1910 the spottings became epidemic in 

 character in Malaya. Even last year (1913) spotted 

 rubber was very commonly met with. The epidemic 

 character of the outbreak necessitated closer investigation, 

 in order to determine the true cause and the methods of 

 prevention. 



Bancroft first demonstrated the mycelium of fungi in 

 spots taken from infected samples. Later he performed 

 inoculation experiments in two cases, proving that the 

 spottings could be reproduced artificially by inoculating 

 latex with spores obtained from pure cultures. Further 

 isolation experiments conducted by Bancroft led him to 

 suggest three other fungi as causes of spottings, but no 

 inoculation experiments were performed with these three 

 fungi. The following work was carried out in order to 

 gain fuller information regarding the cause and methods 

 of prevention. 



