224 
Attention is directed to the differences in the nature of the 
two attacks. According to the descriptions from other countries 
of the activities of P. Fabe ri in the bark of Hevea brasilier&is, 
this fungus might be considered responsible for both Malayan 
outbreaks. The essential differences are such that the evidence 
practically ey Sih conclusion that two different fungi are 
operating. In N a Phytophthora rapidly penetrates the 
wood in a radial and erie baa! ection with practically no lateral 
extension. Assuming the Negri Sembilan outbreak to be caused 
by the same fungus “it is aathable that under similar condi- 
tions, the fungus does not penetrate the wood, but is confined 
entirely to the bark, extending quickly in a lateral direction. 
Dastur has evident tly met some difficulty in reconciling the 
available evidence to the view that the one fungus, Phytophthora 
aberi, is responsible for the varied bark troubles in rubber ‘in 
the Middle East. 
He says (3) ‘‘It seems Ap that we have in Hev 
aiifroat species of Phytophthora causing two distinct Find at 
diseases instead of one fun os causing two distinct symptoms of 
one disease. Of these two different species one is P. Fabert 
which causes Hevea canker identical with that of Cacao as shown 
y the inoculation experiments of Petch and Rutgers; and the 
other species causes Streepjeskanker or Black Thread disease as 
seen from the inoculation experiments made by Rutgers in Java 
me in ai’ 
“isles observations are important in the light of this state- 
ment. The writer had no i aha on pronouncing upon the 
identity of ihe Phytophthora isolated from N. Perak specimens, 
but it ba be interesting to know gor ar it agreed wit 
P. Faberi, Maub. in va to test Dastur’s conclusion. As far 
as Bass records go, there appears to be no previous case where 
the egemhi lee has een isolated in pure culture from the 
py tissue 
growing countries has been ined by an b gonitig with opportuni- 
ties to investigate the kind in all places where Bark disease 
is prevalent. For Malayan plantations the question is a serious 
one as is indicated in the following article. 
e detailed account with measures adopted to combat the 
Pc eae outbreaks has been written for the Agricultural 
Bulletin, Federated Malay States. 
en rs a a ee Roe: ee 
