. Bulletin of the Department of Agriculture. Agriculture; Agriculture. IZSTHERITAI^CE OF WAXY El^DOSPERM IN MAIZE. 59 question were homozygous for the same color factor and heterozygous for the other. The percentage of white seeds is a fairly close approximation of per cent expected on a 11 to 5 ratio, but the assumptions necessary to account for this ratio on ears that result from self-pollination are too absurd to permit such an explanation. The relations of these ears are shown in figure 8. Here again we have evidence of a change in the effect produced by the factors, but since t
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. IZSTHERITAI^CE OF WAXY El^DOSPERM IN MAIZE. 59 question were homozygous for the same color factor and heterozygous for the other. The percentage of white seeds is a fairly close approximation of per cent expected on a 11 to 5 ratio, but the assumptions necessary to account for this ratio on ears that result from self-pollination are too absurd to permit such an explanation. The relations of these ears are shown in figure 8. Here again we have evidence of a change in the effect produced by the factors, but since the same plant behaved normally when crossed with a sister plant in respect to both male and female gametes we must assume that whatever the change it was not suf- ficient to affect the results except where the changed gamete was received from both parents. If we look upon ear No. 1862 as being a deviation from a dihybrid ratio, there is an excess of colored seeds. If the assumption. Fec/./862 /S6/ /c$77 Fig. 8.—Diagram showing the relations of ears Nos. 1862, 1861, and 1871. is made that this excess is due to a fractionation of one of the factors, this altered factor must be the one for which the plant which bore No. 1871 was homozygous. Thus the plant which bore ear No. 1862 was forming gametes CR^ Cr^ cR.) and cr. If we assume that a sufficient amount of the factor R was included in the gamete Cr' to make the union of the two gametes Cr' result in a colored zygote the ratio of white to colored seeds would be altered and the percentage would be white, a percentage closely approximated by ear No. 1862. (See Table XXVI.) This change, however, was not sufficient to produce color when combined wifh a pure Cr gamete obtained from the sister plant, as is shown by ears Nos. 1861 and 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 perfect
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