FUNGUS DISEASES 97 



healthy bananas have been substituted for unhealthy 

 ones. 



Some loss * is caused among banana plants in Fiji by a 

 disease locally called the " banana disease." It shows its 

 presence in the dwarfing of the plant and a rather sudden 

 tapering off towards the crown, where the leaves are small 

 and yellowish green. If the upper part of such a plant is 

 cut open, the leaves which have not yet appeared above 

 the plant will be found to be crumpled up, and will lengthen 

 out considerably immediately on being released. There is 

 doubt as to the exact nature of the disease, which has been 

 in Fiji for eighteen years ; and although plants have been 

 imported from different parts of the world, they seem to be 

 as subject to the attack as the local plants. On digging up 

 a diseased plant, many of the roots will be found to be 

 black and rotten ; and on examining a little of the decom- 

 posed root under a microscope very many nematode worms 

 are to be seen together with fungal hyph. 



3. DISEASES OF THE FRUIT 



RIPE ROT FUNGUS, FRUIT ANTHRACNOSK OR 



BLACKENING f (Glceosporium musarum Cke. and Mass.) 



This disease chiefly affects ripe or ripening fruit, and its 

 presence is marked by black blotches, which spread over 

 the surface, causing rotting. It is due to the attacks of a 

 fungus that occurs in the black areas in the form of a 

 pinkish dust -like substance that is closely sprinkled over 

 them. This matter is composed of the massed spores of 

 the organism, that adherent to one another issue through 

 point-like orifices in the skin, and are connected with 

 mycelium (spawn-threads) growing throughout the adjacent 

 tissue. The dust -like spores are readily detached, float 

 about in the air, and promptly sprout when they settle on 

 a damp surface, sending their germ-tubes into the injured 



* " Report on Agriculture for the Year 1909, Fiji." 

 f H. Tryon in Queensland Agric. Journ., xxviii. 286 (1912) ; W. Ind 

 Butt., x. 260. 



