40 



HISTORY AND CAUSE OF THE COCONUT BUD-EOT. 



instrument that will reach at least 30 centimeters from the surface of 

 the trunk inward. These conditions probably account for the diffi- 

 culty which different investigators have had in obtaining infections. 

 Naturally, the right organism to cause the disease must first be 

 obtained, although infection can probably be accomplished by using 

 the juice of a seriously diseased tree. The matter of isolating specific 

 bacteria is of course desirable, but presents greater difficulties. Ever 

 since beginning the work the writer has occasionally obtained excel- 

 lent rots at the point of infection with apparent^ different organisms. 

 It has been said that any mechanical wound of the heart tissue will 

 cause it to rot and die. This statement is proved to be untrue by the 

 check inoculations and by some inoculations into the heart which 

 failed to take and produced no rot whatever. 



During the investigations of the writer in various parts of the West 

 Indies, from January to June, 1907, diseased material was obtained 

 from many different trees affected with the bud-rot, and bacterial 

 organisms were isolated from these tissues. The cultures isolated 

 consisted, in general, of two types: One which produced, usually, 

 round, wet shining, white, and semiopaque colonies with raised sur- 

 faces; and one (the type most abundant) which produced colonies of 

 very thin growth, spreading rapidly over the plate in an irregular 

 fashion, often sending out long radiating branches. This most abun- 

 dant type was also white, wet shining, and semitransparent. Com- 

 parisons were made of the cultures obtained from Cuba, Jamaica, 

 Trinidad, and Demerara, but they were not found to be identical in 

 their cultural characteristics. Notwithstanding this, several of the 

 cultures were taken the following Februar}-, 1908, to Baracoa, Cuba, 

 and there inoculated into apparently healthy trees. Together with 

 these cultural inoculations wounds were made with a sterile instru- 

 ment to serve as checks. Table I gives the data concerning all of 

 these inoculation results. 



Table I. — Inoculations of coconut trees, February and March, 1908. 



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