. Cyclopedia of farm crops. Farm produce; Agriculture. SOME OF THE PRINCIPLES OF PLANT-BREEDING 67 need be given no attention. The knowledge of Mendel's principles may not change greatly the practical methods of breeding which have been followed for a number of years, but they give us a more thorough comprehension of what we are do- ing, and also greater surety that certain combina- tions of parental characters can be secured. (2) The use and fixation of intermediate or blended types. The principle of the purity of the germ-cell, if strictly applied, would not recognize as possible the fixatio
. Cyclopedia of farm crops. Farm produce; Agriculture. SOME OF THE PRINCIPLES OF PLANT-BREEDING 67 need be given no attention. The knowledge of Mendel's principles may not change greatly the practical methods of breeding which have been followed for a number of years, but they give us a more thorough comprehension of what we are do- ing, and also greater surety that certain combina- tions of parental characters can be secured. (2) The use and fixation of intermediate or blended types. The principle of the purity of the germ-cell, if strictly applied, would not recognize as possible the fixation into a race reproducing true to type of an intermediate hybrid, that is, one in which two characters of a certain pair are blended. Yet practical work shows that such a fixation certainly can be secured. In very many hybrids of plants cultivated for their flowers, intermediate colors have been bred to stability, showing that the inheritance is blended. The writer has been at- tempting to fix a hybrid of Black Mexican sweet corn having blue-black kernels, with Stowell's Evergreen, which has a nearly white kernel, into a race of light blue-violet color, and strictly inter- mediate in this respect between the two parental varieties. Ordinarily, the color of these hybrids breaks up in Mendelian proportions, but neither color can be considered to be dominant in the true sense of the word. In practically all cases when the potentialities of the two characters are mixed in the same egg-cell, the coloration is intermediate rather than like one or the other of the parent vari- eties. The writer has uniformly .selected the seed of such intermediate light blue-violet kernels for planting, and has kept the patch completely iso- lated. After four years of such selection, a type that produces nearly uniformly light blue colored kernels has been produced. There are still many reversions to the coloration of either parent, but these are growing fewer and the type is becoming fixed into a sta
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectagriculture, bookyear
