174 RED ROT OF SUGARCANE. 



hccilthy seed can be assured and new varieties can be introduced 

 into cultivation as required. 



Systematic and thorough selection of the setts used for planting 

 must then be done each year or the new varieties will not maintain 

 their freedom from disease for long. The methods to adopt are 

 described in a previous paper' which should be referred to, and 

 present no difficulties in practice. We consider that there is no 

 single operation in the cultivation of thick canes in most parts of 

 India of greater importance than this. It is not to be anticipated 

 that the disease can be got rid of by a single selection nor, indeed, 

 usually got rid of in its entirety by annual selection ; the most that 

 is claimed is that it can be kept within reasonable hmits in normal 

 years and with good cultivation. The object of the selection is to 

 prevent an accumulation of red rot to such an extent as materially 

 to reduce profits and render it difficult to obtain a sufficient supply 

 of sound seed for the coming season. 



Of lesser importance, but still worth doing in most cases, is the 

 regular removal of all withering clumps during the growing and 

 ripening season. Such clumps, if left, dry up and produce spores, 

 sometimes in considerable quantity. Infection of even perfectly 

 sound cane through the aerial root eyes and through injured buds 

 has been shown to occur and though our experience in Northern 

 India has been that such infection is not common, it is perhaps more 

 frequent in Madras, where the disease appears to be more virulent 

 and rapid in its onset than with us. There is, also, the danger of 

 infection through the soil, especially in irrigated cane, by means 

 of the shed spores. 



Judging from Godavari experience it is important to give cane a 

 long rotation. How far this results from the pecuhar circumstances 

 of cane cultivation in heavy paddy soils, with very frequent irriga- 

 tion, is not clear. In the Godavari Delta, the old practice was eight 

 or nine years' rest from cane after a two years' cane crop (one year 

 plant cane and one year ratoon). More recently, it has been reduced 



1 Butler, E. J., loc. cH., 1907. 



