. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. SPECIES HYBRIDIZATION 237 ticularly striking. These Fi hybrids are completely sterile with their own pollen. However, it was possible by pollinating the hybrids either with pollen from wheat or rye to obtain a few viable seeds. For wheat pollina- tion the ratio of success was about 3 in one thousand; for rye only on(^ plant was secured from nearly five thousand trials. The pollen grains of the hybrids were apparently completely non-functional, and cytological examination indicated prevailingly irre
. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. SPECIES HYBRIDIZATION 237 ticularly striking. These Fi hybrids are completely sterile with their own pollen. However, it was possible by pollinating the hybrids either with pollen from wheat or rye to obtain a few viable seeds. For wheat pollina- tion the ratio of success was about 3 in one thousand; for rye only on(^ plant was secured from nearly five thousand trials. The pollen grains of the hybrids were apparently completely non-functional, and cytological examination indicated prevailingly irregular divisions and behavior in their production. The product of back-crossing the Fi hybrids to wheat gave plants 1 4 , 1- i^ ^J ' 1 â ' f 'i,' jV â t V \ V 1 i A e C. Fig. 100.âSterile hybrids be- Fig. 101.âSesqui-iiybrids from theFi wheat X tween wheat and rye, A, the wheat rye crossed back to wheat. (After Jescnko.) parent; C, the rye parent, and B, the Fi hybrid between them. {After Jesevko.) very similar to wheat. This is illustrated in Fig. 101. Although all these plants resembled wheat in their general characters, they neverthe- less showed wide differences from one another, not only in morphological characters but in physiological ones such as fertility as well. A few of the plants were totally sterile, but some of them were more or less fertile and in general those were most fertile which most closely resembled the wheat parent. In the next following generation, the progeny of those plants which were most fertile consisted of plants which were apparently pure wheat and completely fertile and plants which were less like wheat and showed lessened fertility as the resemblance to wheat decreased. Digitized by Microsoft®. 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 Babcock, E. B. (Ernest Brow
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Keywords: ., bookcentury1900, bookdecade1910, booksu, booksubjectplantbreeding
