vi TEA 177 



violet, black when fresh, and are the discoloration already noted. 

 They advance along the vessels of the wood, and, as these are 

 the channels by which the water ascends, the hyphae stop the 

 supply of water either by filling the tubes or by perforating the 

 cross walls. 



In most respects, this disease bears a close resemblance to 

 the " Internal root rot " of Assam. This attacked young bushes, 

 usually not until after the first pruning. There was nothing 

 externally to indicate the cause of death. The leaves of the 

 plants took on a yellow appearance in which the network of 

 the veins was very prominently seen, and they then began to 

 die off branch by branch. Though the effects are exactly the 

 same, the fungus is said to be different from the Ceylon species. 

 The latter is an ascigerous fungus Massaria theicola, while the 

 former is Diplodia vasinfecta, a non-ascigerous species. 



All diseased parts should be pruned and burned, and 

 the wounds painted with tar or other protective substance. 

 If the attack is severe, the stems should be painted or 

 sprayed thoroughly with Bordeaux mixture. 



Bark Disease. Corticium Zimmermanii, Sacc. & 

 Syd., and C. javanicum, Zimm., are the causes of severe 

 bark diseases (see page 64). 



Root or Stump Fungus. There are a great many 

 fungi which cause diseases of the roots of tea and other 

 plants. Two or more species of Rosellinia have been 

 reported from India and Ceylon, one of which is R. 

 bunodes, and another is probably R. radiciperda, Massee, 

 attacking the tea, camphor, and other plants. They are 

 most abundant on recently cleared forest land. The 

 leaves of the diseased plants wither and turn brown and 

 the tree gradually dies within about two weeks. 

 Examination of the roots will show them to be covered 

 with a brown incrustation, under which will be found 

 the delicate, white mycelial threads of the fungus. 

 The hyphae penetrate the cortex and form white, star- 

 shaped growths on the wood. When the tree is dead 

 the mycelium appears above the ground and covers the 

 lower part of the stem with a black velvety coating and 

 produces millions of conidia spores. It is doubtful if 

 this fungus can germinate on a living root, but after 



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