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mediately averaging better than the parents. the first progeny will average much poorer tha Its great value lies in throwing together qual plying variations, both of which may be deve tion. This greatly increased variation has be the ground that "the wheat plant being so clo there is within it, lying dormant, a wonderful (a power far greater than in plants cross-fertil which is thrown into action when different va

ficially crossed.'' 1 As to these varieties Hay

further they have departed from ancestral cha formed diverse qualities, the more likely will th hibit new characteristics made up by combini have become so radically different in the two pa

1 Carleton, Basis for Improv. of Amer. Wheats 2 Plant Breeding, p. 37.

also arise characteristics so new in kind and degree that they can hardly be considered as a mere combination of any characteristics found in the parents. All of the so-called "botanical" classes of wheat have been produced by hybridizing two varieties, a fact which "certainly indicates blood relationships between the classes of wheats."

Since the qualities originated by hybridization must be developed by selection, it may take years before the value of the hybrid can be determined. The advantage in large numbers lies in the fact that "only one individual in several thousand has marked power to produce a valuable strain." These individuals have been called the "Shakespeares of the species," and the labor of eliminating by selection all of the other individuals is 99 times that of producing the hybrids. By the usual method, the seeds to be tested and selected are planted individually in rows 4 or 5 inches apart. If any promising plants develop, 100 seeds from each are again planted. These groups of plants from single parents are called centgeners. By means of selection, crossbred wheats can thus be reduced in four or five generations to a type so uniform that little or no variation will occur among plants in the field. Whether they will retain their acquired characteristics has been questioned. Hybrids originated by Hays and Saunders seem to do So. The question as to whether wheat will deteriorate under self-fertilization is still an open one.

In breeding a variety of wheat, the ideal to be held in mind constantly is "that it yield the largest possible amount of grain of the best quality for the purpose desired under given conditions.'' 2 In such a course botanical appearances seemingly I will take care of themselves.

Historical. The sexuality of plants was proved experimentally by Camerarius (1691). The first recorded hybrid was produced by Thomas Fairchild (1719), an English gardener, who crossed the carnation with the sweet william. The publi

cations of Koelreuter (1761) paved the way for the work of Thomas Andrew Knight (1800), the eminent English plant physiologist, who has been called the father of plant breed1 Hays, Yearbook U. S. Dept. Agr., 1901, p. 229. 2 Scofield, Algerian Durum Wheats, p. 7.

ing. The first hybrid produced in the United States was probably a pear (1806). The importance of hybridization in relation to variation was demonstrated by Naudin and Nägeli (1865).

The pioneer producer of wheat hybrids in America was C. G. Pringle of Charlotte, Vt. He began his work in 1877, and several varieties have received his name, some of which have become standard. Pringle's Defiance has been a rust resistant variety of California since 1878. During his connection with the Colorado agricultural college A. E. Blount produced quite a large number of hybrids, some of which are now well known in the United States and are also among the most valuable varieties in Australia, both as field wheats and as parents of native hybrids. The most important are Amethyst, Improved Fife, Hornblende, Gypsum, Blount's No. 10, Felspar, Ruby and Granite.

The director of the experimental farm at Ottawa, Canada, Dr. William Saunders, began hybridizing wheats in 1888. His main object has been to procure early ripening varieties, and he has attained success by hybridizing American and Russian races. Preston and Stanley are two of his best productions. In the main these hybrids have been produced in the most simple way. A. N. Jones of Newark, N. Y., practicing composite crossing, though always with quite closely allied parents, has done the most important work in wheat hybridization in this country, and his varieties are now the most widely used of all recent American wheat hybrids. The two features characteristic of his work have been composite methods, and high gluten content as an ideal. The nature of the soil and climate of eastern United States is such as to produce soft and starchy wheats. His efforts have been to raise the standard of eastern varieties as to gluten, and he has largely succeeded. Winter Fife and Early Red Clawson were the two most popular of his first varieties. Early Genesee Giant, another well-known variety which he originated, is widely grown in New York and Pennsylvania. It has no ancestors outside of the common bread-wheat group. This seems to be a weak point in Jones' method of procedure, for the most advantageous composite crossing is supposed to be with varieties of entirely different wheat groups.

This gives by far the greatest variations in degree and number, and gives qualities not otherwise obtainable. For example, the highest degree of non-shattering must be obtained from spelt or emmer, while the quality of resistance to leaf rust is best acquired by crossing with the durums. Jones' Winter Fife could not be grown in the Palouse country on account of its shattering, though it yielded 60 to 65 bushels per

acre.

The Garton Brothers of England and William Farrer of New South Wales have extensively practiced crossing the different wheat groups. Every variety and every intergradation results from such crossing. A local variety may acquire, not only rust resistance and tenacity of chaff by intercrossing with a spelt and a durum, but also greater fertility of the head drawn from the spelt, and increased vigor of the seed, which produce a higher yield. These, and increased hardiness and gluten content, are practical results attained by the Garton Brothers. William Farrer has done an immense amount of excellent work in improving Australian wheats, especially as to rust resistance. The most important work in breeding cereals on the continent has probably been done by W. Rimpau of Schlanstedt, Germany, though his work is not generally characterized by composite methods. The Vilmorins have also done work in this line. The Dattel, one of the most widely distributed varieties of wheat around Paris, was originated by them.

Breeding Experiments have been carried on in the Kansas wheat belt for some years, and extensive co-operative work in this line has been taken up with the experiment stations in different wheat growing states, particularly in Texas, Kansas, South Dakota, Minnesota and Maryland. Efforts are being made to secure a variety that will ripen a few days earlier, so that by sowing two varieties the harvest period can be lengthened, and the danger of green cutting and shattering be avoided. Wheat and rye have been successfully hybridized by a number of experimenters, but as yet with no valuable results.

Experience has taught that the most successful and practical way to fight disease is to aid natural selection in producing disease-resistant or immune plants, rather than to attempt to

proportion to its cost must appeal to everyone, its permanency. Luther Burbank made the stat a new wheat were bred that would yield only on to each head, Nature would produce annually, wit cost for man, 15,000,000 extra bushels of wheat i States alone.

The conclusions of scientists seem to be that not wear out or materially change if the same con made them excellent are kept up. If special care to produce an artificial variety, this care must or it will deteriorate. The improvement of whea is no longer a theory, as in the time of Darwi tablished fact.

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