184 STUDIES IN INDJAN SUGARCANE SEEDLINGS 



r LEAF WIDTH AND THICKNESS OF CANE. 



Correlation 7. 



It is natural to assume that thick canes will have broad leaves, but the 

 results of our studies have not always turned out' as we expected them to, as 

 in the case of leaf width and sucrose, where it was at first thought that the 

 wider leafed forms, resembling the thicker canes of the trojncs would have 

 better juice. It is true that, the thicker the stem, the wicfei the base foi leaf 

 attachment ; but we have noted in our study of the Punjab canes^ that near 

 relatives vary as to the extent to which the base of the leaf ensheathes the 

 stem, and also that the relative width of lamina and leaf sheath varies a good 

 deal at the point of junction. No help can be got from the ])revious tables 

 where both the leaf width and stem thickness give or tend to give negative 

 correlation with richness of juice. It was thought worth while, accordingly, 

 to test the matter, and tlie results aie given in the accom])anying table. From 

 its study we see that there is a very definite positive correlation between 

 leaf width and thickness of cane. This is seen in all the seedlings of the general 

 collection and in the Velloi cross. But in the other cross there is merelv a 

 tendency to a positive correlation and the differences in thickness in the 

 classes of leaf width is remarkably small. In the Naanal seedlings, on the other 

 hand, there is no trace of correlation either way. the whole of the classes varv- 

 ing slightly in an irregular manner, another case in which these puzzling 

 seedlings arc at variance with the other geiuMal collections. The Pooran 

 seedlings are too few for any distiiu-t corrt^latioii to be discernible. 



' Bftihcr, C. A. Mew. Dfpl. Agri.. India, Bot. Ser. vol. VII, n... 1, ]i. 28. 



