Edible Products, 



514 



[December, 1909. 



The crossing I effected in 1897 showed, 

 on the contrary, after four years, not a 

 single descendant affected by this 

 disease, Encouraged by these results, I 

 continued the crossing of these two 

 varieties for several years, and only a 

 very few of the descendants appeared 

 liable to sereh or root disease. On the 

 other hand, several of them had to be 

 rejected because they were too thin, 

 some canes not being thicker than one- 

 fifth on an inch ; again, others would 

 not do because the fibre contents were 

 too high, but a large proportion could 

 compete with the two varieties named 

 before, and, especially in the Eastern 

 part of Java, many thousand acres are 

 now covered with the descendants of 

 of our seedlings, Nos. 36, 139, 213, 228, etc. 



In 1901 Mr. Moquette was the first 

 manager who had all his cane fields 

 planted with seedling canes ; in 1908 

 probably the majority uf our factories 

 did so. While twenty-five years ago, in 

 Java, probably 99 per cent, of the cane 

 fields were planted with Cheribon canes, 

 nowadays perhaps only 10 per cent, are 

 not yet replaced by seedling varieties. 

 Among these, Nos, 247 and lOO are now 

 prominent, each of them covering 30-35 

 per cent, of the whole surface under 

 canes, while nearly 20 per cent, of the 

 area is planted With our own seedlings. 

 No. 247, however, is not quite immune 

 against the sereh disease, though not 

 affected in such a way as the Cheribon 

 cane, and No. 100 is rather difficult to 

 rear having regard to the quality of the 

 soil, 



We are trying now to breed new 

 varieties, superior to those already culti- 

 vated, and I intend to give a short review 

 of the methods by which we hope to 

 arrive at our goal. 



In the first place we have to consider 

 the good and bad qualties of the parent 

 canes, since these are hereditary in a 

 high degree. Cane varieties liable to 

 disease ordinarily give seedlings that 

 suffer badly therefrom ; canes rich in 

 sugar show this property in their pro- 

 geniture ; the yellow spots on the leaves 

 of the Chunnee cane are found in nearly 

 all its descendants, and likewise its 

 immunity against disease. 



The flowers of such varieties as we 

 intend to use for breeding seedlings must 

 be examined by the microscope to ascer- 

 tain whether stamens and ovary are 

 existent and of a normal structure, and 

 whether the pollen is fertile. This can 

 be verified by iodine solution, since 

 pollen without amylum are never known 

 to germinate, 



When we intend to cross two varieties, 

 of course, only those can be made use of 

 that flower at the same time, and as in 

 Java the flowering time of different cane 

 varieties extends from January till July, 

 it is probable that some desirable cross- 

 ings cannot be effected. For crossing 

 purposes, we like to take as female plants 

 varieties without fertile pollen, to make 

 sure that there is no doubt about the 

 parentage of the seedlings. 



To prevent fertilisation by undesired 

 pollens, we cover the arrows with cloth- 

 covered baskets. For self-fertilisation, 

 it is sufficient to cover one single arrow ; 

 for cross-fertilisation, another arrow is 

 tied up in the same basket. Cane flowers 

 open their stamens early in the morning 

 hours; most varieties at 5-6 a.m., some 

 others till 9 a.m. After 9 o'clock, pollen 

 can rarely be found in flowers that 

 opened in the morning, and are fit for 

 cross-fertilisation (in some varieties the 

 pollen grains stick together and are not 

 spread by the wind), 



As five days elapse before all the 

 flowers of an arrow have opened, we 

 usually insert male arrows in the basket 

 for five successive days, choosing such 

 arrows of which we were sure a part of 

 their flowers would open the stamens 

 next morning. To prevent the drying 

 up of the stamens in the night, the male 

 arrows are placed in a bamboo filled 

 with water. The cloth-covered baskets 

 that are used to breed pedigree seed- 

 lings, are protected by a large hat to 

 prevent the rain spoiling the pollen and 

 the fertilised flowers. 



In this way we are pretty sure to get 

 such crossings as we desire, though there 

 are instances where flowers with well- 

 developed ovaries did not give one single 

 seedling, notwithstanding that they 

 were crossed with very fertile pollen. 

 The reason why this has not been dis- 

 covered so far, a microscopical examina- 

 tion showing nothing abnormal in the 

 structure of the ovary. One unexpected 

 drawback, however, was met with in 

 later years, when we found that cane 

 varieties rich in sugar only rarely have 

 good pollen. 



With such crossing as have proved a 

 success and that are repeated every 

 year, we select the parents the year 

 before by chemical selection, to have 

 some certainty that not only the cane 

 variety used, but also the individual 

 parents are rich in sugar. During one 

 year, by comparing over a thousand 

 seedlings of canes poor in sugar, with 

 as many seedlings of parents belonging 

 to the same varieties but rich in sugar, 

 we found that the latter were the best 



