70 



Pink Disease of Plantation Rubber 



Necator spores germinate readily in distilled water and in nutritive 

 solutions (Fig. 10). 



Fig. 9. Section of fully developed Necator pustule, x 400. 



In Malaya the Necator has been found much more frequently than 

 the basidial stage and it is likely that it takes the more active part in 

 the dissemination of the disease. 



The other forms of Corticium salmonicolor are constantly sterile. 



Fig. 10. Germination of Necator spores, after 12 hours in damp chamber. x 400. 



The fungus is probably chiefly spread by wind, though it is possible 

 that it is also disseminated by red ants and other insects which visit 

 rubber trees. It is possible too that not only spores but also small 

 portions of the sterile incrustation are disseminated by these means. 



