. Advanced biology. Biology; Physiology; Reproduction. METHODS OF ANIMAL PROPAGATION 353 treated, are saved and planted. When these new plants produce fruit, only the best seeds are selected. Frequently, the young plants are grafted upon other trees to hasten the growth. Hy- bridization is but the beginning of breeding. Careful selection must be continued, so that a pure type is established. Methods of animal propaga- tion. If a mutant with a desir- able character is found, it is bred. In case the new character is dom- . inant, it will appear in the Fi generation, but the animal of this genera
. Advanced biology. Biology; Physiology; Reproduction. METHODS OF ANIMAL PROPAGATION 353 treated, are saved and planted. When these new plants produce fruit, only the best seeds are selected. Frequently, the young plants are grafted upon other trees to hasten the growth. Hy- bridization is but the beginning of breeding. Careful selection must be continued, so that a pure type is established. Methods of animal propaga- tion. If a mutant with a desir- able character is found, it is bred. In case the new character is dom- . inant, it will appear in the Fi generation, but the animal of this generation will be hybrid. This hybrid is then mated with an animal which shows the same desired character. Sufficient matings must be made to get the character in a pure form. This sometimes necessitates close breeding. By close breeding is meant mating individuals closely ^^,^ f ^^^^ P^^f^ s'L^^^!" clusters, it is a ° "^ small plum, smaller than the American plum. related, as grandparent with off- when these two plums are crossed, an im- ^ proved plum, much larger than either parent, spring of the second, third, or is produced growing in bunches like the .. parent Beach plum. succeeding generations. I he tact that animals frequently take a number of years to mature is a serious difficulty met with in animal breeding. Close breed- ing does not necessarily reduce the vigor, but, if there are unde- sirable characters present, they may be doubled and the offspring, then, cannot be used for breeding purposes. In case the new character is recessive it will not appear until the F2 generation. Then, if two individuals of different sex of this generation pos-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Wheat, Frank Merrill; Fitzpatrick, Elizabeth T. New York ; Boston [etc. ] : American Book Company
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Keywords: ., bookcentury1900, bookdecade1920, booksubje, booksubjectphysiology
