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inches above and below the point of infection and the charac f eristic 

 spore sacs and spores had developed under the bark near the point of 

 infection. 



4. An experiment was now performed in order to determine whether 

 infection could be obtained by spores without first of all piercing the 

 bark. A drop of water containing the spores of the fungus under dis- 

 cussion was placed on a branch of an adult cacao tree and covered 

 with a small glass cell which was sea'ed to the bark with budding wax 

 and shielded from the sun. After seven days it was found that al- 

 though the spores had germinated no penetration of the bark could be 

 detected. Time did not permit of further experiments on this point 

 and the evidence as far as it goes points to the probability that infec- 

 tion of the cacao tree takes place at wounded surfaces in the bark. 

 Obviously only a very small wound is necessary such for example as a 

 minute crack or the hole made by a " boring" insect. 



These infection experiments leave no doubt that the " brown-rot" 

 fungus of the pod also attacks the cacao tree and that the young cul- 

 tivation referred to above had been badly attacked by this pest. For- 

 tunately, however, these experiments indicate that a wound is gene- 

 rally necessary for infection to take place, a point of which great ad- 

 vantage can be taken in combating the disease. 



Remedial Measures — In suggesting remedies for fungoid diseases 

 like the one under discussion it is obvious that when once the fungus 

 is well established in a tree or pod nothing can be done to save the 

 portions attacked, and that attention must be directed to prevent fur- 

 ther infection by assisting the tree9 to ward off attack and by des- 

 troying as far as possible everything in the cacao plantation which 

 harbours the spores of the fungus. In this way, the pest can be 

 kept well in hand and fu'ure trouble avoided. The following measures 

 are suggested in dealing with this pes. :— - 



1. All husks or shells of the cacao pod should be buried as soon as 

 possible after the beans have been extracted. This practice is carried 

 out on many of the best estates in Grenada at the present time with 

 very good results and it, is hoped that it will soon become a part of the 

 regular estate routine all over the island When the pods are al- 

 lowed to remain on the ground they are really nurseries for the 

 "brown-rot" fungus and speed' ly becomes covered with spores, thus 

 serving as centres of infection of the disease. If they are buried fresh 

 this fungus does not develop, decay sets in, and the resulting humus 

 improves the texture of the soil. Lime should be mixed with the 

 fairly fresh pods so as to hasten decay and prevent local souring of the 

 soil which may easily damage the neighbouring trees, esp cially if the 

 buried heaps are large. It would be well if the " breaking-grounds" 

 were moved from time to time so as to give as many trees as possible 

 the benefits of this manuring. Old black pods which have been lying 

 on the ground for some time and which are covered with spores should 

 be collected and burnt. 



2. All pods in which brown-rot is detected should be picked at 

 once so as to prevent the disease spreading to the tree through the pod 

 stalk. If this is done early ,the beans can be saved. The husks of 

 these pods should be buried away from the cacao trees or burnt. On 

 no account shoul I the beans from these pods be used for growing seedlings. 



