Vol. XV. No. 374. 



THE AGRICULTURAL NEWS. 



275 



uiiately 2s.; in the case of cotton seed meal it is Is. 5d. 

 (when the meal is at £7 per ton). Both of these prices 

 are abnormally high, but taking into consideration what 

 has been said concerning the organic nature of the 

 meal, and its potash and phosphoric acid content, it 

 would seem that for general purposes it would be 

 cheaper to use cotton seed meal than sulphate ot 

 amuionia, or at least a mixture of the two. A de- 

 finite decision on this point, however, depends 

 largely upon the circumstances of each case, and 

 may best be left to the individual planter to decide 

 for himself We may be content here simply to 

 state the facts of the matter, trusting that their 

 enumeration may be found useful and suggestive. 



CANE BREEDING AND SELECTION IN 

 PORTO RICO. 



The benefit conferred upon the sugar-cane grower 

 through the selection work that has been conducted for many 

 years in Barbados and British Guiana is not confined to the 

 agriculturists of those colonies alone. This can be readily 

 realized from the large amount of attention ihat is being 

 given to Barbados seedUngs and methods of seedling 

 production in Porto Rico. Here, two lines of experimenta- 

 tion are in progress: (1) comparative tests of Barbados and 

 Denierara canes with the Porto Rico standards, namely, 

 Yellow Caledonia and Otahaite, and (2) cane-breeding work 

 which has included cross-pollination experiments. 



In the Fourth Repoit of the Boards of Commissioners of 

 Agriculture of Porto Rico, for the period .July i, 1914 to 

 June 30, 191.5, it is stated that several varieties have given 

 noticeably better returns than the re.st. Sealy Seedling has 

 made a better showing than any of the others, considering the 

 quality of the juice and the weight of cane produced. B. 17.53, 

 I).117, D. 109, and B. 4596 have also given excellent returns. 

 B. 208 gave better results as a second ratoon than as a first. 

 This cane was found to be very susceptible to the effects 

 of dry weather, a characteristic which this cane is known 

 to possess in the British islands. It is stated that the past 

 year with its better rainfall was much more favourable for 

 the growth of this cane than the previous one. A further 

 experiment with introduced varieties more recently obtained 

 was started during the year, and amongst those canes wiich 

 so far appear promising are B. 1809, B. 724.5, B. 6292, 

 B. ?8-59, B. 340.5, and B. 3747. All these varieties yielded 

 higher in this experiment than either Crystalina or Otahaite, 

 which were used as controls. 



Turning to cane-breeding work, it is stated that an 

 efiort was made during the past year to obtain seedlings 

 from cross- pollinated seeds. Mention is made of attempts 

 in Barbados to adopt the method of emaculation and hand 

 pollination. Such a method has been tried without success 

 in Porto Rico. Attempts in Porto Rico during the past year 

 have followed the method tried, among others, by Mr. J. D. 

 Kobes in Java. The varieties to be cros.sed are planted in 

 parallel rows with the pollen-sterile variety on the leeward 

 .side of one which is pollen-sterile, and which blooms at the 

 same time. A large number of seedlings were produced from 



the tassels of the pollen-sterile varieties, and there can be 

 little doubt that they were from cross-pollinated seeds. The 

 pollen-sterile variety in this case was the Otahaite, and the 

 pollen-fertile parent, B.347. Ordinarily the Otahaite cane 

 produces tassels with a very small proportion of fertile seed. 

 All attempts previously made with it in Porto Rico have 

 given a very poor germination, and very few seedlina canes. 

 This year, with B.347 growing on the windward side, and 

 both flowering abundantly at the same time, the germination 

 was excellent. This is a good indication that the flowers were 

 cross-pollinated, and very probably almost entire!)- by the 

 adjacent variety, B.347. Because of the way that the 

 stigma lobes projpct from the glumes, cross-pollination seems 

 to be very easily possible. 



Another method was also tried with some success. It 

 consisted in tying together the tassels of the varieties to be 

 crossed, before the florets of either opened. Crystalina and 

 1"). 109 were the varieties used, Crystalina being the pollen- 

 sterile parent. A smaller number of .seedlings were produced 

 by this means, but the results were equally sitisfactory. 

 There is perhaps more liability of getting crossed seed by 

 this method. 



CHICLE GUM. 



Attention having been drawn to the statement that the 

 Sapodilla tree (Achrnx Sapota, L.) in the West Indies does 

 not freely yield the gum known as 'Chicle', while trees 

 supposed to be of the same .species growing in Central 

 America yield freely, complete herbarium specimens of the 

 Dominica tree were, in 1914, forwarded to Kew, together 

 with a sample of gum for investigation and report. 



The tree from which the gum was obtained is about 

 twenty years old. The trunk, which is 39 inches in girth 

 at 3 feet from the ground, was thoroughly tapped from the 

 base up to a height of 8 feet. The yield of latex was 

 3i fluid oz.. which gave If oz. of cried miterial. 



There being no demand for Chicle gum in England, 

 the Kew authorities were unable to obtain a commercial 

 opinion on the sample forwarded. Consequently another tree 

 was tapped and the sample of gum submitted to a firm of 

 produce brokers in New York, who reported as follows: — 



'Your sample of gum, which we received under separate 

 cover, has been submitted to one of the largest chewing gum 

 manufacturers in this country, and after tests in their 

 laboratory they write as follows: "We can in all probability 

 use some of this, provided (luantity could be furnished, 

 therefore, beg to enquire how much can be supplied promptly, 

 and also if arrangements could be made to have it come 

 along regularly, and what quantities." ' 



In the meantime herbarium specimens of the Chicle gum 

 tree grown in British Honduras were received at Kew. To 

 the present it has been thought that two, possibly three, 

 species of Achras are involved, and that the Dominica plant 

 appears to be distinct from the British Honduras variety. 

 Further information on this matter is awaited with interest. 



Owing to the low yield of gum, the Achras common 

 throughout the West Indies is not likely to become of 

 importance in this respect, although the report from New 

 York shovi's the giun to be marketable, if obtainable in 

 quantity. Its chief value lies in the excellent fruit which 

 the best varieties furnish, and which might still be further 

 improved by careful selection experiments. (Report on the 

 Agricultural Department, Doniinici, 1914-1-5.) 



