. Maize; its history, cultivation, handling, and uses, with special reference to South Africa; a text-book for farmers, students of agriculture, and teachers of nature study. Corn; Corn. 164 MAIZE CHAP, reference to the most striking or important characters, and speak v- of a plant as being homozygous for this or for that character. 127. The Heterozygote.—The heterozygote is formed by the union of gametes bearing the two characters of an allelomorphic pair (if 129). It is the progeny of parents which are dissimilar in some, or all, characters, and may be either exactly like one parent, or may
. Maize; its history, cultivation, handling, and uses, with special reference to South Africa; a text-book for farmers, students of agriculture, and teachers of nature study. Corn; Corn. 164 MAIZE CHAP, reference to the most striking or important characters, and speak v- of a plant as being homozygous for this or for that character. 127. The Heterozygote.—The heterozygote is formed by the union of gametes bearing the two characters of an allelomorphic pair (if 129). It is the progeny of parents which are dissimilar in some, or all, characters, and may be either exactly like one parent, or may have derived some visible characters from each parent, in which case it will not be exactly like either, in all its main characters. The progeny of a heterozygote are unlike; some are more or less like one, and some like the other parent, while some are unlike either. 128. Unit-Characters.—We learned from the preceding chapter that in maize the two gametes or sexual cells, which unite to form a zygote, often come from separate plants. These two plants may belong to different breeds, having different characters. We know from experience that if a white dent breed is fertilized with pollen from an ordinary pure-bred yellow dent breed, the resulting grain ( of the first generation) will be yellow dent, but that in the fol- lowing generation some grains on one and the same ear will be white and some yellow; or that if we cross a sugar breed,havingwrinkled. Fig. 71.— A heterozygous ear of the F2 seed generation of a cross between black wrinkled and white dent (IT 127). grain, with pollen of a flint breed having rounded grain, the resulting grain will be round and flinty. That this is due not merely to what has sometimes been called " prepotency of the. 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 w
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Keywords: ., bo, bookcentury1900, bookdecade1910, booksubjectcorn, bookyear1914
