ARTIFICIAL PRODUCTION OF NEW SPECIES.

New Zealand Graphic, Volume XLI, Issue 3, 15 July 1908, Page 39

ARTIFICIAL PRODUCTION OF NEW SPECIES.

Professor MacDougal, who has been for some years engaged upon the problem of the artificial production of new species of plants by injecting various salts into the ovaries of the flower, claims to have obtained novelties in several genera. The most notable one is a form derived from Oenothera biennis, which he calls “F. 206,” in which the new plant has remained true for several generations. It is easily distinguished from the parent species, and, furthermore, does not readily hybridise with it. Experiments are in progress on the effects of calcium nitrate, zinc sulphate. methyl-blue, in various strengths of solution, on a considerable list of plants, e.g., Cercus, Nieotiana, and Pentstemon. <h course, the failures arc numerous; that is only to be expected, mot only on the grounds of the difficulties of manipulation, but also because the organism might altogether fail to respond to the substances used. The pount of view from which the work is being carried on may be most easily grasped by the following quotation from a lecture

delivered in Chicago by Professor MacDougal: “The forms ami qualities exhibited by organisms represent the total effect of environment; but it cannot be shown that this has been brought about by direct adaptation; many of the most highly specialised and useful structures, bear only an indirect relation to the factors to which they bear a useful relation. Neither has it been demonstrated that an individual adjustment made by the soma is impressed upon the germplasm. and transmitted unchanged. . . . Various agencies experimentally applied in such manner as to affect the germplasm only have caused the origin of forms bearing fully transmissible qualities not presented by the parental type. The new characters have been found to be fully heritable, and the induced forms do not always hybridise with the older types. The induction of such new forms in plants may be accomplished by re-agents applied to the generative nuclei carried by the pollen-tube, and probably by action on the embryo-sac, in the period following reduction division. Mutations have been taken, on hypothetical grounds, to be based on changes occuring previous to these divisions. The various agencies used in inducing new forms in this manner may have a stimulating effect, or may cause direct disturbances in the chemical balance of the substances in the chromatin and plasma. Similar action may result from unusual intensities of various environmental conditions, or to accidental intrusions on germ-plasm of many kinds. The alterations in question may well be beyond detection by cytological, or by any direct method of examination. When the nature of the induced changes is once ascertained, the inductive agents might be applied in such manner as to guide the course of development and thus actually control the evolution of organisms. By such methods, man. the conscious organism, might assume a dominating role in the world of organisms and create relations among living things not now existent.” If further research should substantiate the claims made by Professor MacDougal, it will readily bo seen that a powerful instrument is within our reach for inducing variation. But it must be clearly understood that the variations are likely, if producible at all. to be empirical. There can hardly be any question of “adaptation.” What will have been effected is an alteration of those chemical processes which finds expression in the particular character of any individual plant, and if we can really alter these we shall at the same time doubtless modify the whole organism. For this chemical machinery, germplasm. physical basis of inheritance, or by whatever other name we call it. is the really important thing. If once this can be got at and changed, then variation must inevitably follow, and if the change were permanent in its character, the corresponding variation may also be expected to be stable. But it will be wise not to expect too much, at any rate, for some time to come. Even if it should turn out to be possible to induce variation in this way at all. it of course does not follow that the new forms would be improvements upon the old. In the world around us we see variation enough brought about by natural causes, as we say. but the real advances, from the economic or aesthetic point of view, are few enough. In stimulating the formation of new varieties, as now practised, we have the advantage of dealing with processes such as crossing, the rules governing the results of which are gradually becoming better appreciated. Whether a similar outcome is to be anticipated from injection methods still remains to be seen. Some doubt may perhaps be legitimately felt as to the correctness of the interpretation of the change which has been found to occur in the ease of the plants experimented on. We know already that OEnothera Lamarckiana is constantly throwing off more or less stable variations, and OE. biennis is closely related to it. May it not be possible that natural variation may have occurred in the experimental plots, and have been mistaken for an artilieiallyinduced one’ Criticism is, however, premature at the present time. The future will soon show how far the new variations are the result of natural conditions, ami how far they are to be attributed to the effects of a direct action of the substances employed upon the germ-plasm of the species. “Gardener’s Chronicle.”