NECTRIA 187 



The mycelium extends much beyond the point indicated 

 by the fungus on the surface, hence cuttings should not be 

 taken from diseased plants. Diseased branches should be 

 removed and burned, as should also infected branches and 

 twigs lying on the ground. 



Mayr, Unters. Forstbot. Inst. Munchen, iii. p. i. 



Cacao trunk disease. Mr. J. B. Carruthers has published 

 a report on this disease in Ceylon, of which the following is 

 a summary. The fungus concerned is obviously a species of 

 Nectria, allied to the disease causing apple-tree canker. The 

 earliest indication of the disease is a darkening of a patch of 

 the bark ; if this patch is cut out it is found to be soft, of a 

 claret colour, and full of moisture. At a later stage minute 

 white pustules appear, especially in cracks ; these eventually 

 become pink. During the white stage, very minute, oval 

 conidia are produced in immense numbers, and later on 

 larger crescent-shaped conidia appear. Finally, when the 

 cortex is dead, or nearly so, a third ascigerous form of fruit 

 appears, the sporangia being globose and grouped in 

 clusters. 



The disease often spreads rapidly ; in one instance, a 

 diseased patch more than two feet long, and reaching almost 

 round the tree, had formed ten days after inoculation. 



The most satisfactory method is to cut out the diseased 

 patch, along with a margin of apparently sound bark. 

 Covering the wound with tar is recommended. 



Carruthers, The Tropical Agriculturalist^ Nov. T, 1898, 

 P- 359- 



Pigeon-pea and pepper wilt. A dangerous disease attack- 

 ing the pigeon-pea (Cajanus indicus] in India, is described 

 by Dr. Butler. The symptoms are as follows : at first 

 withered plants show here and there when the seedlings 

 are a few inches high, other plants near those first attacked 

 dry up, and patches of dead plants become more frequent 

 as the season progresses. A period of hot, dry weather 

 during the rains favours the disease, and large patches of 

 withered plants appear with startling rapidity. On examina- 

 tion of a badly diseased plant, the root is found to be 

 blackened and dead, blackish streaks also extend up the 

 branches for some distance, and may be seen on removing 



