May 1907. J 



t Sanitation. 



layer. The edge of the growing sporophore is white, in old specimens it is red and 

 horny. In the photograph, the sporophore is jnst above the collar, (i.e., half way up 

 the figure), and the red edge is well marked on the lower side. The minute holes 

 are the openings of close-packed tubes in which the spores are produced. The fungus 

 thus belongs to the same family as that which causes root disease in Hevea. It was 

 named Porta hypolateritia by Berkeley years ago from Indian specimens, and owes 

 its name to the underlying hard, red layer. 



This appears to be the fungus which spreads to the tea from the roots of 

 Symplocos spicata, the Bombu ; but in some instances jungle stumps are not 

 present, and it seems probable that the infection in these cases is brought about by 

 spores. The fungus is fairly common in upcountry jungles on dead logs, e.g., at 

 Hakgala and Pattipola. 



Lowcountry Tea Root Disease. 



In the lowcountry districts, all root disease in tea appears to be caused by 

 one species of fungus. The indications on dying roots are not as clear as those of 

 Poria or Rosellinia, but there is no difficulty in finding them once they have been 

 pointed out. The roots show small black nodules or warts, which probably give rise 

 to underground mycelium, though this has not been clearly established. The 

 mycelium between the wood and bark spreads in white or yellowish fan-shaped 

 patches which acquire a black edge when they meet a crack in the bark. Irregular 

 black lines are seen in a cross section of the root. 



The fructification appears on the lower part of the stem, emerging through 

 a crack in the bark in the form of a white swollen cushion. This spreads over the 

 surface as a more or less flattened white plate which finally becomes grey and 

 concentrically zoned. The photograph shows two fructifications on the right, one 

 half ripe and the other just developing ; the latter is not yet zoned. The remaining 

 fructifications (on the left) have been spoilt to some extent by insects. When quite 

 ripe, it is a grey, concentrically zoned plate marked with minute black dots : it lies 

 close to the surface of the stem but is only attached at one point. The under surface 

 is black, and the whole structure is hard and brittle. Two kinds of spores are 

 produced. The first are borne on the outer surface when the fungus is wholly white ; 

 the specimen (in the photograph) just developing is in this condition. The second 

 are produced when the fungus is quite ripe, in minute chambers whose openings are 

 the black points previously referred to. The fungus is an undescribed species of 

 Ustulina. Its distribution in the lowcountry has not yet been ascertained, and it 

 is not yet known whether it spreads to the tea from any particular species of tree. 

 There are specimens in the Herbarium, collected in 1868, labelled " Central Province, 

 and South of tlie Island ;" these agree in shape with the form described above. A 

 slightly different form occurs on tea bushes in the field ; this grows to a height of 

 half an inch, beginning with a very thin base, and widening out to a flat circular top, 

 about a quarter of an inch in diameter. Several of these structures grow together, 

 and the group then resembles a different order of fungi ; but they develop with the 

 other form under cultivation, and sometimes the heads fuse into the usual large 

 flat plate. I have gathered the fructification from tea bushes which showed hardly 

 any sign of disease, and it seems most probable from this, that the progress of the 

 fungus is very slow. 



Rosellinia. 



Rosellinias are fairly plentiful in the tropics. There are twelve species 

 among the fungi collected by Thwaites, and one of these, Rosellinia bunodes, has 

 been found to be the cause of root disease in Southern India. It has recently been 

 collected in Ceylon but, as far as is known at present, it is not one of those which 

 attack tea in this country. There appear to be two species on tea, one of which also 



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