146 HISTORY AND CAUSE OF THE COCONUT BUD-EOT. 



to produce soft rot in the ordinary vegetables which are affected by 

 various kinds of the so-called soft-rot organisms. It seems to the 

 writer, however, that it has been clearly shown that the colon organism 

 can produce a soft rot in a certain vegetable tissue, namely the coco- 

 nut bud tissue. Not even the recognized soft-rot organisms can 

 produce this sort of decay in all of the ordinary vegetables; so the 

 mere fact that the colon organism and the so-called soft-rot organism 

 do not affect the same tissues is not sufficient argimient for placing 

 them in widely separated groups. The writer does not contend that 

 all these organisms are by any means the same, but that there is at 

 least a very close relationship between all of them. It is probable 

 that the whole group of these organisms represents a class extremely 

 variable, and able in some of its many forms to adapt itself to a great 

 variety of conditions. In this question, of course, hybridization plays 

 no part. It is purely a matter of vegetative changes. Surely there has 

 been enough shown in variation of vegetative parts of flowering plants 

 to warrant the conclusion that the vegetable units resulting from the 

 bacterial division may differ sometimes in their biochemical reactions 

 from the original units. From cultural studies it would seem as 

 though the life processes of the bacteria were even more delicately 

 balanced, and that this balance is more easily overthrown than in the 

 higher plants. 



BUD-ROT ATTRIBUTED TO CAUSES OTHER THAN BACILLUS COLI. 



With a knowledge of the cause of bud-rot and with a thorough 

 understanding of the effects of the bacterial organism, the source of 

 all the trouble, one may compare more intelligently the various dis- 

 eases of the coconut palm as reported by different workers. That 

 disease of the tree which is characterized by a rot of the heart of the 

 crown has been attributed to numerous causes. The most important 

 of these wliich have been seriously proposed by practical coconut 

 growers and by scientific investigators are worthy of some considera- 

 tion. Of late the general trend of oi)inion has been to admit the pos- 

 sibiHty of bacteria producing the rot, but to claim that some other 

 cause was responsible for the presence of the bacteria. Such reasons 

 as soil with too much lime, with too much clay, wdth too little salt; 

 soil too dry, too wet; insects; and fungi; all of these and other minor 

 reasons for the presence of tliis disease have been given. 



The preceding pages have shown distinctly that the bud-rot may 

 be actually induced by means of a wound inoculation into an appar- 

 ently healthy coconut tree; in other words that the bacterial organ- 

 ism already described is an active parasite. It is only reasonable to 

 assume that some condition unfavorable to the proper growth of 

 the tree will do much to facilitate the work of the bacterial parasite. 



228 



