. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. Fig, 153.—Diagram to show formation of adventitious buds arising at the point of anion of the two graft-components A and B. a, represents a sectorial combination; b, a perielinal combination. (After Budcr.) claims is a true graft-hybrid, was named Darivinianum. It appeared on one of the shoots from a decapitated graft. Winkler claims the chromo- some number of this form is 48 and that certain if not all of the tissues of this plant ai'e composed of cells derived from the actual fusion of tomato wit
. Genetics in relation to agriculture. Livestock; Heredity; Variation (Biology); Plant breeding. Fig, 153.—Diagram to show formation of adventitious buds arising at the point of anion of the two graft-components A and B. a, represents a sectorial combination; b, a perielinal combination. (After Budcr.) claims is a true graft-hybrid, was named Darivinianum. It appeared on one of the shoots from a decapitated graft. Winkler claims the chromo- some number of this form is 48 and that certain if not all of the tissues of this plant ai'e composed of cells derived from the actual fusion of tomato with nightshade cells which involved nuclear fusion. If this is actually the case S. Darwinianum is a hybrid in the strict sense and the only one known to have been produced by vegetative means. However, Baur points out that Winkler bases his claim for this number on the grovmd that he found 24 chromosomes in the pollen mother-cells which arise from the sub-epidermal layer. Baur thinks that Winkler's interpretation is unwarranted. He believes it much moi-e probable that S. Darwin- ianum is a perielinal chimera with a nightshade epidermis, then a sub- epidermal layer of tomato cells and the adjoining inner tissues of night- shade. Then the number found, 24, is the diploid number of the tomato and the reduction division, according to this explanation, is omittcKl in the tomato pollen mother-cells which, in this chimera, are bounded on both sides by nightshade tissues; or else it occurs at an unusually late stage in development. "I cannot admit," says Baur, "that the exist- ence of real graft-hybrids in the strictest sense of the word is ; 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 Brown), b. 1877; Clausen, Roy Elwood, 1891-. New Yo
Size: 1860px × 1343px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksu, booksubjectplantbreeding
