and Magazine of the Ceylon Agricultural Society.— Sep., 1910. 271 



chance for the disease to spread rapidly. The 

 fungus gains entrance to the stalks entirely 

 through wounds in the rind, similar in this re- 

 spect to the rind disease. 



A stalk affected with this disease does no' 

 usually show on the outside. The exterior of the 

 cane may be perfectly sound in appearance, while 

 the interior may be badly decomposed. On split- 

 ting the stalk, however, the disease can usually 

 he to!d if the disease has progressed to any ex- 

 tent, the centre of the stalk will be more or less 

 decomposed. The sugar containing cells have 

 been disintegrated; the fibruvaseular bundles 

 of the central region will be seen to be more or 

 less free. This central cylinder, or " pipe " as it 

 is called, is nearly black in colour. If the disease 

 has not progressed far enough, however, to show 

 this black color, it can be brought out in a very 

 few hours by placing the split stalk in a moist 

 place. This black colour is duo to the presence of 

 the spores of the fungus, and they develop very 

 rapidly on a cut surface in a moist place. 



Then ifthe whole stalk is not as yet af- 

 fected, there will generally be a sharp boun- 

 dary between the diseased and the healthy 

 joints. The fungus grows very rapidly through 

 the internodes, but is halted for a time at 

 each node. Of course, the stopping of the 

 fungus at the node is only for a short time. 

 It is soon able to pass this point aud then 

 rapidly grows through the next internode. 



Another characteristic point in regard to the 

 disease is the odor given off by the affected 

 stalks. The odor is described as similar to 

 that of ripe pineapples, and on this account 

 it has received the name of the " pineapple 

 disease." The disease does also affect pine- 

 apples in the tropics, but it did not get its 

 name from this. The odor is supposed to be due 

 to acetic ether, the same as in the pineapple. 

 However, in all the canes which 1 have had, 

 the odor could be readily told from that of 

 pineapples. The odor is an ethereal one, some- 

 times quite strong and penetrating and is, in 

 fact, very pleasant to the smell. 



Treatment of Sugab Cane Diseases. 

 With our present knowledge of the sugar 

 cane diseases, it will only be possible to oner 

 a few suggestions in regard to their control. 

 The problems in regard to the control and 

 treatment of these diseases are very difficult 

 ones. The fungi which are responsible for the 

 diseases are more or les-s at home in the soil 

 and it is difficult to work with them. 



Id order to' control a disease, we must oither 

 remove entirely from the locality all material 

 which contains any germs of the disease, or 

 we must protect the plant in such a way so 

 that it will not come in contact with any of 

 the germs. Either of these by itself is im- 

 possible, but we can take measures to remove 

 a considerable part of the infectious material, 

 and we can also treat the plant so that il is 

 partly protected from contact with the disease 

 erms. The treatment of an outbreak of a 

 isease is similar in certain respects with man, 

 animals, and plants. If a house has had 

 smallpox in it, the first thing that is done is 

 to clean the house out and fumigate it. If a 



field of cane has had the rind disease or the 

 pineapple disease in it, why not uso the same 

 methods here? Why not clean up the field? 

 The cleaning up of a field is a very important 

 point, especially with the rind and pineapple 

 disease. These diseases develop very rapidly on 

 any old cane material that may be left in the 

 tieid and it is not an exaggeration to say that 

 there are millions of spores developed on each 

 stalk. If there is a considerable amount of 

 these old stalks aud other cane trash left on the 

 ground, the spores of the diseases will become 

 so abundant in the field, that every planted 

 cane will be exposed to infection. If, however, 

 the fields are thoroughly cleaned up in the fall', 

 a large amount of this infectious material will 

 be destroyed. 



After the soil is thoroughly infected with 

 these clisoases perhaps the only thing that will 

 insure a good stand of cane is the treatment 

 of the seed cane with some fungicide. Both 

 the rind disease and the pineapple disease 

 enter the seed through wounds or the cut ends 

 of the stalks. The nnd is impervious to the 

 attack of these fungi. The object desired in 

 treating cane cuttings is to thoroughly cover 

 them with some compound that is poisonous 

 to the fungi causing the diseases and one that 

 will also not injure the eyes. The best so- 

 lution which we have at present for this is 

 Bordeaux Mixture. The treatment of seed 

 with this is not only practicable, but is highly 

 profitable in tropical sugar countries. Of 

 course, special machinery and special tanks 

 are used, so that a large amount of seed can 

 be run through the solution in a short time. 

 Whether the treatment of the seed would be 

 profitable to the Louisiana planter in normal 

 years is a question, but I am convinced that it 

 would have been profitable during the past dry 

 season. And if the pineapple disease spreads 

 over the state and does as much damage as it 

 does in the tropics, the treatment of the seed 

 will not only be profitable but it may become a 

 necessity. 



Such insects as the borer are very important 

 in the spread of the diseases in that they pro- 

 duce wounds through which the fungi enter, it 

 is very important that they should be kept 

 down as much as possible. 



Another point in regard to treatmeut is that 

 of selection of the seed cane. This is very im- 

 portant especially with the red rot. This fungus 

 does not fruit to any great extent and so does 

 not spread very fast in the field. If perfectly 

 healthy cane were planted each season, the 

 disease would cause but little damage. But 

 when the diseased cane is planted the disease 

 spreads upwards into the young stalks and the 

 eradication of the trouble is impossible. The 

 most desirable thing would be to select carefully 

 all the cane to be used for planting throwing 

 out any that shows any exterior signs of disease 

 or any that are attacked by borers. However, 

 as this would hardly be practicable on a large 

 scale, perhaps the best method would be to 

 select enough to plant a few acres and use the 

 cane that grows from this for planting the full 

 crop of the next year.— Louisiana Planter and 

 Sugar Manufacturer, June 11. 



