100 



THE AGRICULTURAL NEWS. 



April 6, 1918. 



NOTES ON CASTOR-OIL IN THE WEST 



INDIES. 



Owing to the increased ileimxnd for the oil obtained 

 from the seeds of the Castor oil plant many planters are now 

 considering the advi.-ability of growing this crop on 

 a comniereial scale. 



Experiments were carried on in Antigua for a numher 

 ■of years with four varieties of castor-oil, ami the results 

 indicated that the cultivation of this plant was not likely to 

 be commercially succe.«sfii), owing to the low yield obtained. 

 As an example of the tluctuatiou in yield, the results of the 

 two seasons 1910-11 and 191112 may be alluded to. In 

 1910-11 the yield from ' acre with four varieties planted 

 5 by 4 feel was at ilie rate of 2101b. per acre, ai.d tiie young 

 plants were severely attacked by aphis. In 1911-12 the 

 yield was at the rate of l,97CBu per acre. It is evident that 

 the yield obtained from this crop may be largely affected by 

 environmental conditions, and the incidence of insect pests. 



Xeveriheless, further work may result in the production 

 of types which will give better results, and a number of 

 observations have been made by the present writer which 

 may serve to assist those who intend to grow castor-oil. 



The first step in any proposed set of experiments would 

 be to collect as many ditt'erent varieties as possible, and test 

 them comparatively under ihe particular environmental 

 conditions with which the experimenter is concerned. When 

 work was started at the Ci>rnell 1 'niversity Experiment Station 

 in connexion with ihe production of new and improved 

 varieties of Timothy grass, no Itss than 223 lots of seeds were 

 tested, and these were obtained from all parts of the world. 

 It is not perhaps generally realized that there exist in the 

 West Indie."! an enormous number of morphologically different 

 types of castor-oil, and these would probably be tViucnl to v.-iry 

 very widely in characters of commercial importance. 



Thus in St. Vincent and Barbados, an examination of the 

 scattered groups of plants growing near peasants' huts 

 showed the following differences in respect of morphological 

 character: — 



(1) Types with anthocyanin colouration in stems and 

 leaves. 



(2) Types with no anthocyanin colouration in stems 

 and leave.s. 



(.3) Types with a waxy bloom on stems and immature 

 fruits. 



(4) Types devoid ofbKom. 



(5) Seeds not easily freed from husk.s. 



^6) Seeds easily freed from husks. These types often 

 shed the seeds on the ground, and an excessive development 

 of this habit is to be avoided in selection work. 



(7 1 Capsules with spines strongly developed. 



1 8) Capsules practically devoid of spines. 



Besides these obvions differences it was also noticed 

 th»t the size and colour of the seed varied greatly from 

 jjlant lo plant. i 



In connexion with Ihe character noted above under 

 (5), it may be staled thai one of the chief obstacles met with 

 in the .\ntigua experiments was that the seeds were very 

 difficult to shell. It is ijuite evident, however, that the 

 dirficulty will not be a leal one, provided that the right type 

 is chosen for growing. 



In the Antigua experiments .spacing between the plants 

 ■was 5 by 4 feet. It is most important that the effect of different 

 spacings on yield should be carefully investigated. From 

 some preliminary experiments in St. \'incent, the writer is 



inclined to think that with some types closer spacing might 

 give belter results. 



At the St. Vincent Experiment Station a hybrid was 

 made between a native type and a variety named Riii/ius 

 (ri/isoiii, obtained from .Messrs- Ityder, of St. Alban's The 

 characters of the parents and of the F, may be tabulated 

 as follows: — 

 T/ic /•', i;ciicratii'ii. 



Native. K. Gibsoni. F, 



Anthocyanin colour- Leaves and stems Intermediaie,but 



ation weakly devel- a bronzy purple, nearer to Native 



oped in stems and owing to strong 



leaves. development of an- 



thocyanin colour- 

 ation 



Waxy bloom present 



on stems and imma- Waxy bloom absent. Intermediate. 



ture fruits. 



Seedsnotea.dlyfreed Seeds very easily Intermediate, 

 from capsule. fieed from capsule. 



Seeds very small. Seeds larger. 



Apparently in- 

 termediate. 



Pattern of seed dark Pattern of seed pal- Pattern of seed 

 brown. er brown dark brown, and 



much more 

 strongly develop- 

 ed than in either 

 parent. 



77u' T'o geiieratidii. 



In the second hybrid generation such an enormou.s range 

 of variation occurred in respect of both morphological and 

 physiological characters ihit, with the limited amount of 

 time at the writer's disposal, a detailed examination of the 

 plants was out of the question. The only character which 

 was carefully gone into was the inheritance of the wAxy 

 bloom, segregation of the parental types being quite wel! 

 marked. 



The following numbers were obtained: — 



Bloom as in Native. Bloom intermediate Bloom absent. 

 as in F , 

 1(»1 2.'i(> 11. ■< 



From these results it is probable that the presence aod 

 absence of wax in Hicious constitute a Mendeliau piir. 



A general survey of the plants showed a re-a|ipearance 

 of all the characters <A both parents, and, in addition, others 

 not possessed by the latter. Some of the new characters 

 appeared to be of economic value; e. g. one or two plants 

 po.ssessed a larger number of fruits to the spike than either 

 parent Certain of the plants po.ssessed the habit of shedding 

 the whole cajjsule as soon as it became ripe. This character 

 is obviously an undesirable one. 



Without entering into the subject in a very detailed 

 manner, it may be said that until exhaustive experiments on 

 a large scale have been carried out in the West Indies, it 

 mu.st H'main an open .jue.stion as to whether the cultivation 

 of this crop i.s likely to be a commercial .success. At the same 

 time the writer does not know of any institution in Ihe West 

 Inilies which has sufficient resources at its command to carry 

 out such a series of investigations. 



S.C.H. 



