140 studies in indian sugarcane seedlings 



Leaf Tips. 



One of the most striking habit differences in cultivated canes is the 

 foim assumed by the ends of their leaves. Some, like Shahirchijnia 

 (Pi. VI, fig. 3), have stiff, unbending tips ; others have a sharp bend or 

 break near the end, as in most, if not all, of the Chin alliance (Chin, 

 Sarelha, Hatha, Kansai\ Lalri)^ ; others again, although moderately stiff', 

 soon bend slightly as in the Mungo group ; while the Panmhi group, 

 consisting of Pamahi, Yuba, Maneria, Lata, Dickchan, Sanachi, Kahu^ 

 etc., have broad leaves which, from the first, soon bend in wide and 

 graceful curves. There are similar differences in almost every batch of 

 seedlings which has been examinetl. It is true that in many plants this 

 curving of the leaf ends depends a good deal on the rate of growth and 

 the amount of food and moisture available. Differences can be seen in 

 any field of young cholam oi jaar {Androfogon Sorghum) (PI. XXV), and on 

 the banks of the railways among the various specimens of the strongei- 

 wild grasses, but, considering the fact that it is attempted to grow all the 

 seedlings under identical conditions and that the varieties of cultivated 

 •canes differ so markedly in. this respect at maturity, a good deal of attention 

 has justifiably been given to the leaf tips in examinijig the seedlings. The 

 bending does not seem to have anything to do with the width or the 

 length of the leaf, nor with the general conditions of the plants and, 

 accordingly, one of the first selections has been to pick out all the i)hints 

 with strict, erect leaves whose tips do not soon bend. It was generally 

 possible, in the 1914-16 seedlings, to obtain about 10% in each batch 

 with erect tips, but Cheni and Java showed a stronger tendency towards 

 this character. Most of the seedlings had leaves soon broadly curving, 

 while here and there it was possible to pick out such as were disthiguishcd 

 by the leaves being bent back so that the ui)})er part was almost paralk'l 

 with the lower (c/. Pl. XVII). 



Width of Leaf. 

 There is great variation in the width of the leaf in any biitcli of seedlings 

 of common j>arentage (PI. XXVI), while the general average width in different 

 batches often hints at their parentage. In fifty young Cheni seedlings (1914-16) 

 this variation was from 0*45" to 0"90", the broadest leaf being chosen in each 

 case, and in Kaludai Boothau the difference was between 0"6" and 1'3". At 



1 Earbcr, C. A. lUem. JJepl. Ayr. J ml. Bui. !Seriei>, \'ol. Vll, No. 1, l^ls. HI and IV. 

 2 Ibid, PI. XVI. 



