Scientific Agriculture. 



46 



, [January, 1912. 



pure science, and those who engage in it 

 must be prepared for a long period of 

 labour without ostensible practical re- 

 sults. It has seemed to me that the 

 most likely method of attack is here, as 

 often, aa indirect one. We should prob- 

 ably do best if we left the direct and 

 special needs of agriculture for a time out 

 of account, and enlisted the services of 

 pathologists trained in the study of 

 disease as it affects man and animals, 

 a science already developed and far 

 advanced towards success. Such a man, 

 if he were to devote himself to. the 

 investigation of the same problems in 

 the case of plants, could, I am convinced, 

 make discoveries which would not mere- 

 ly advance the theory of disease-resist- 

 ance in general very greatly, but would 

 much promote the invention of rational 

 and successful treatment. 



As regards the application of Genetics 

 to practice, the case is not very differ- 

 ent. When I go to the Temple Show 

 or to a great exhibition of live stock, 

 my first feeling is one of admiration and 

 deep humility. Where all is so splendid- 

 ly done and results so imposing are 

 already attained, is it not mere imper- 

 tinence to suppose that any advice we 

 are able to give is likely to be of value ? 



But so soon as one enters into conver" 

 sation with breeders, one finds that 

 almost all have before them some ideal 

 to which they have not yet attained 

 operations to perform that they 

 would fain do with greater ease 

 and certainty, and that, as a matter 

 of fact, they are looking to scientific 

 research as a possible source of the 

 greater knowledge which they require. 

 Can we, without presumption, declare 

 that genetic science is now able to 

 assist these inquirers ? In certain select- 

 ed cases it undoubtedly can— and I 

 will say, moreover, that if the practical 

 men and we students could combine our 

 respective experiences into one head, 

 these cases would already be numerous. 

 On the other hand, it is equally clear 

 that in a great range of examples 

 practice is so far ahead that science can 

 scarcely hope in finite time even to 

 represent what has been done, still less 

 to better the performance. We cannot 

 hope to improve the Southdown sheep 

 for its own districts, to take a second 

 off the trotting record, to increase the 

 flavour of the muscat of Alexandria, or 

 to excel the orange and pink of the rose 

 Juliet. Nothing that we know could 

 have made it easier to produce the 

 Rambler roses, or even to evoke the 

 latest novelties in sweet peas, though it 

 may be claimed that the genetic system 

 of the sweet pea is, as things go, fairly 



well understood. To do any of these 

 things would require a control of events 

 30 lawless and rare that for ages they 

 must probably remain classed as acci- 

 dents. On the other hand, the modes 

 by which combinations can be made, 

 and by which new forms can be fixed, 

 are through Mendelian analysis and the 

 recent developments of genetic science 

 now reasonably clear, and with that 

 knowledge much of the beeder's work is 

 greatly simplified. This part of the 

 subject i3 so well understood that I need 

 scarcely do more than allude to it. 



A simple and interesting example is 

 furnished by the work which Mr. H. M. 

 Leake is carrying out in the case of 

 cotton in India. The cottons of fine 

 quality grown in India are monopodial 

 in habit, and are consequently late in 

 flowering. In the United Provinces a 

 comparatively early-flowering form is 

 required, as otherwise there is not time 

 for the fruits to ripen. The early varie- 

 ties are sympodial in habit, and the 

 primary apex does not become a flower. 

 Hitherto no sympodial form with cotton 

 of high quality has existed, but Mr. 

 Leake has now made the combination 

 needed, and has fixed a variety with 

 high-class cotton and the sympodial 

 habit, which is suitable for cultivation 

 in the United Provinces. Until genetic 

 physiology was developed by Mendelian 

 analysis, it is safe to say that a practical 

 achievement of this kind could not have 

 been made with rapidity or certainty. 

 The research was planned on broad 

 lines. In the course of it much light 

 was obtained on the genetics of cotton, 

 and features of interest were discovered 

 which considerably advance our know- 

 ledge of heredity in several important 

 respects. This work forms an admirable 

 illustration of that simultaneous pro- 

 gress both towards the solution of a 

 complex physiological problem and also 

 towards the successful attainment of an 

 economic object which should be the 

 constant aim of agricultural research. 



Necessarily it follows that such assist- 

 ance as genetics can at present give is 

 applicable more to the case of plants 

 and animals which can be treated as 

 s annuals than to creatures of slower 

 generation. Yet this already is a large 

 area of operations. One of the greatest 

 advances co be claimed for the work is 

 that it should induce raisers of seed 

 crops especially to take more hopeful 

 views of their absolute purification than 

 have hitherto prevailed. It is at pre- 

 sent accepted as part of the natural per- 

 versity of things that most high-class 

 seed crops must throw " rogues," or that 

 at the best the elimination of these 



