BUTLER AND klAFlZ.. 155 



agreed in considering it remarkably free from red rot, and in holding 

 the injury to the roots caused by the storm responsible for most of 

 the damage. AVe also found evidence of the existence of a root 

 disease not previously kno^Yn, which will be described in a subsequent 

 paper. In 1909-10, red rot was still present on the farm but to a far 

 less extent than heretofore. In 1910-11, very little disease was noted 

 either on the farm or in the nursery, though it was still fairly preva- 

 lent outside the farm. In 1911-12, red rot was present only to a 

 small extent, though found in nearly all the varieties, l^^rom these 

 records it is clear that red rot has not been stamped out by sett 

 selection. It is equally clear that the disease is much less prevalent 

 than in the early years of the existence of the farm. The farm 

 was started as a result of a disastrous outbreak of red rot in the 

 Godavari Delta, which threatened the extinction of cane cultivation 

 in that area. It is fair to assume that the local varieties, which were 

 at first grown, were very largely from diseased stock. So long 

 as these varieties were retained, sett selection did not give satis- 

 factory results. When they were replaced by other, comparatively 

 healthy varieties, sett selection was effective in keeping the disease 

 under control. 



It is now necessary to consider why sett selection has proved 

 ineffective in checking disease when the seed was taken from a 

 severely diseased crop. 



In selecting healthy setts for planting under field conditions 

 reliance must be placed on the absence of obvious reddening of the 

 pith, visible at the cut ends. Disease was severe in the Pusa crop 

 of 1907-08 and the opportunity was taken of testing how far this 

 method could be relied on. On November 21st, 1907, 6 canes were 

 selected which, on cutting into lengths, were found to have reddened 

 internodes above and below, but in the middle to be free from obvious 

 reddening. In 3 of these, careful examination with a lens revealed 

 one or two fine reddened points, corresponding with the cut ends of 

 small bundles ; the other 3 appeared quite free from discoloration. 

 Slabs were cut out aseptically and incubated, and the presence of 

 Colletotrichum falcatum was demonstrated in one of the six. On 



