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Show REAL BASIS FOR IMPROVING CORN PLANT There are Three Ways in Which Advancement Can be Secured and Careful Study is Urged. By Edward M. East. Ever since plant breeding has been brought to the front as a means of increasing in-creasing yields and producing new qualities, distinct from the mere feeding feed-ing of crops by means of fertilizers, we have been taught that by selection we could accomplish anything. Take the character length of ear as a concrete example, says Edward M. East in Rural New Yorker. Variations Varia-tions in length are seen in every field of corn, no matter what the variety. If we select the longest ears in successive suc-cessive seaons we are taught that we shall continually improve the strain in this character. Even the teachers have always had an inward con-scibusness con-scibusness that there must be a limit to the progress that could be made in this way, but the thought has been indefinite, and has been designedly kept in abeyance. The man who has been so indiscreet as to ask where the limit of his improvement is to be has been judiciously steered into other lines of thought. Some questions are hard to answer, and it was more interesting in-teresting to let him dream of the time he could fill an order for a bushel of corn with one lone ear. Likewise, we have been taught that by hybridizing two strains we could obtain any desired new character or quality if we only continued on the job for a sufficient length of time. We can probably be made, although some biologists are beginning to lose faith in it because the results scarcely pay for the trouble. This is the selection selec-tion of fluctuations. Fluctuations are the variations that are not due to structural changes in the reproductive cells, but simply to nutrition. They are, therefore strictly speaking not inherited, but simply give temporary aid in the development of the next generation. For example, let us imagine imag-ine two corn plants having exactly the same characters; one of these plants has grown on good soil and is well developed, while the other has grown on poorer soil and is weakly developed. devel-oped. The seed of the well-nurtured plant has more nutriment stored up in it, and the young seedling that it produces has a better start in life than has a. seedling from the poorly-nurtured poorly-nurtured plant. The actual characters charac-ters inherited by the two plants are the same, but the seedlings from the poorly nurtured plant are handicapped, handi-capped, and are not' so well able to utilize their food supply and produce a normal well-developed plant. This is also true of poorly-nourished animals. ani-mals. Let us apply these principles to corn breeding. Corn is a wind-pollinated plant, therefore when a change takes place in the reproductive cells I Samples of In-Bred and Cross-Bred Corn. ot any individual of a vafiety, it is quickly recombined with different characters in other individuals. As these changes take place with some frequency, what we call a commercial commer-cial variety is actually a set of hybrids between individuals possessing possess-ing various characters. The real effect ef-fect of selection is gradually to isolate iso-late a strain having characters that we desire, in so far as such characters charac-ters have already been produced by nature. There is no question of our originating anything by this selection. If there are plants having undesirable characters we can reject them, provided pro-vided there are plants that are without with-out these characters, but that is as far as we can go. In this mixture of types, the commercial variety, there are some strains that produce a greater variety than others. It is the aim of the line breeder to take out these types and discard those having less efficiency. For these reasons we can see how great is the importance ' of our original breeding plot. If the type desired has been included among the original plants it can be selected out and established as a variety, if it has been left out we can only wait for nature to produce such a type. And as nature is not prodigal in her new productions our chances are relatively relative-ly small. have only made a beginning in breeding breed-ing as a science, and it will be many years before we can predict with .the accuracy of a chemical reaction what will take place on crossing two individuals; but even now we know enough of the laws of variation and heredity to show us that this point of view is all wrong. The quality qual-ity of the grist depends upon the grain in the hopper. There are three and only three ways in which plants can be improved, and a careful consideration of them shows the errors in both of the above teachings. teach-ings. 1. Every plant is composed of a large number of characters, each of which- is- inherited as a unit. The basis and the plan by which these characters develop are held in the fertilized fer-tilized egg from which the seed and finally the plant results. From the structure within this egg-cell, each character and through these characters, charac-ters, the entire organization is finally self-constructed by the utilization of food materials from the soil and from the air. No permanent variation occurs oc-curs in a plant unless it occurs first in the structure of these reproductive cells. Such variations are, therefore, the only foundation for plant improvement, improve-ment, and the sole function of selection selec-tion is to pick out the most desirable of them for propagation. Unfortunately Unfortu-nately for the ease of the task, variations varia-tions due to nutrition and other causes, variations that affect the plant and not the reproductive cells are, therefore, not inherited, often obscure the rarer, inherited yariatious, and thereby cause much unnecessary and unavailing selective work. 2. The object of hybridization is to shuffle and recombine the unit characters charac-ters of the parent plant. If we knew what all the results would be when these characters combine we could predict the percentage of the progeny of a cross that would contain certain definite combinations of characters. But we do not know enough concerning concern-ing the inheritance of these characters to make predictions. We simply know that we can only expect to combine the characters actually possessed by the parent. For example, resistance to the disease called watermelon wilt was found to be a single unit character charac-ter possessed by the first cousin of the watermelon, the citron. This quality qual-ity was therefore combined with other desirable qualities possessed by the watermelon by hybridization. Here was definite basis upon' which to work aud by which tangible results could be obtained. But supposing no wilt-resistant melon had been known, it would have been utterly futile to have tried to breed this character into the watermelon by selection. The watermelon water-melon reproductive cell does not possess pos-sess this character, and on this account ac-count there is no basis upon which to select. The kind of selectionist against whom we are speaking would begin by going into a field and taking tak-ing seed from those plants that were the least affected by the disease, yet he wou'd never obtain results because he would be selecting non-affected plants instead of resistant plants. 3. There is a third method by which a slight and temporary improvement |