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Volume 27 (1952)
- Issue 5-6 Pages 131-
- Issue 3-4 Pages 69-
- Issue 1-2 Pages 1-
Volume 27, Issue 1-2
Displaying 1-9 of 9 articles from this issue
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Ryuso TANAKA1952 Volume 27 Issue 1-2 Pages 1-2
Published: 1952
Released on J-STAGE: May 21, 2007
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Shun OKUNO1952 Volume 27 Issue 1-2 Pages 3-21
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSIn the present study, 14 wild species and 36 cultivated varieties and species were dealt with cytologically. They were found to constitute a distinct polyploid series, 2x-3x-4x-5x-6x. Their polyploid relations are given in table 1.
Meiotic division in wild species takes place in the regular fashion in general, with 2 exceptions of triploid forms, Solanum maglia and S. commersonii, which have been considered as natural hybrids derived from a tetraploid form×diploid form. Pentaploid wild form, S. demissum forma atrocyaneum, also has meiotic irregularities, suggesting that it is a hybrid origin.View full abstractDownload PDF (2081K) -
Harushige TAKUSAGAWA1952 Volume 27 Issue 1-2 Pages 22-24
Published: 1952
Released on J-STAGE: May 21, 2007
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Hiroshi NAKAHARA1952 Volume 27 Issue 1-2 Pages 25-27
Published: 1952
Released on J-STAGE: May 21, 2007
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Seizi TATUNO, Kozo WATANABE1952 Volume 27 Issue 1-2 Pages 28-32
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESS1) The chromosomes of Pellia Neesiana has been studied with the acetic-orcein, and which was compared with the results of other various stains, such as aceto-carmine, Feulgen's nucleic acid reaction and Heidenhain's haematoxylin (Table 1).
2) With acetic-orcein can be recognized the chromonema in the euchromosomes and at the part of the heterochromatin in the X- as well as Y-chromosome.
3) At meio is the X- and Y-chromosome conjugate only by the part of the euchromatin of both chromosomes, but not by the part of the heterochromatin.
4) Acetic-orcein is the suitable stain-fixative for studing micro-structure in chromosomes, especially for heterochromatin in bryophytes.View full abstractDownload PDF (505K) -
Tadashi OYAMA1952 Volume 27 Issue 1-2 Pages 33-37
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESS(1) By the irradiation of X-ray on the young shoots in Trifolium repens, morphological abnormalities are always observed in the leaves developing from the treated shoot. Also, there are always some of cytological abnormalities of mitotic figures in the root tip which develops from each of nodes bearing the abnormal leaves.
(2) The abnormalities of leaves represent a high degree of the variability in form and size.
(3) It may be assumed that a parallel relationship exists between the degree of abnormalities of leaves and the frequency of abnormality of the mitotic chromosome in the root tip.
(4) In the root tip, when the abnormal mitosis occurrs of more than about 5 percent in frequency, the shoot was dead, or stopped its further development.
(5) It may be concluded with certainty that a morphological change of abnormal leaves should be recognized definitely in the course of recovering, directly proportional to decreasing of the abnormal mitosis, as follows:
+D→+inc→+P→+mal→+ab→normal
(6) When a complete recovering of the abnormal leaves to the normal ones occurs, abnormal mitosis is observed in most of such shoots. In spite of the healing of abnormalities of mitosis, the constant abnormalities of leaves were however observed in only two cases, one of which was designated to be “E Cri WR or Ecri WW WW” and other to be “ab”. Those two constant abnormal types in the leaves may be considered to be a gene mutation induced by X-ray irradiation.View full abstractDownload PDF (472K) -
III. Reverse mutation found in short arista mutant. (Part 4)Chiyoko TOKUNAGA1952 Volume 27 Issue 1-2 Pages 38-47
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSDuring the course of genetic studies of Aphiochaeta sp. the author has obtained twenty some mutants. Some occured naturally and others as the result of X-ray irradiation. The mode of inheritance is more or less irregular in most cases. Some of those mutated genes have been definitely located on the chromosomes, for instance, short arista (sa°) and Delta on the third chromosome, anb bar and truncate (main gene) on the second.View full abstractDownload PDF (1193K) -
Studies on the development of the gonad in silkworm, IIIKeiichiro MIYA1952 Volume 27 Issue 1-2 Pages 48-55
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESS1) The distribution of germ cells in embryos was observed in four strains of silkworm. It was found that the distribution of germ cells does not confined to any definite bodily segments, but varies according to individuals or strains. Germ cells almost occupy their characteristic position distributing from the 6th to 8th segment, while some are found in the gnathal, thoracal and abdominal segments, besides the above segments.
2) The range of distribution of germ cells in various parts of the embryo seems to be determined at the time of their first appearance, which occurs at the stage of germ-band formation. The distribution of germ cells seems not to undergo influence of expansion or contraction of embryo. The cause which induced the distribution of germ cells in gnathal and thoracal segments is, however, unknown; it seems that it is attributable to the lack of affinity among germ cells.
3) The distribution of germ cells to two sides of the body seems to be taken place by chance. There are some individuals in which the number of germ cells is disimilar in both sides.
4) The germ cells which are found distributed in some segments other than the 6th to 9th segment, take no part in the gonad-formation, and they are destind to degenerate.View full abstractDownload PDF (950K) -
I. Constancy of karyotype in one race as the basis of the karyomorphologyTomoe OINUMA1952 Volume 27 Issue 1-2 Pages 56-64
Published: 1952
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESS1) Constancy of karyotypes in barley species are studied in this paper using the following materials:
Hordeum agriocrithon.......wild six-rowed barley, strain No. 309.
Hosogara No. 2......cultivated six-rowed barley, strain No. 21.
Rokkaku No. 1......cultivated six-rowed barley, strain No. 38.
Harbin Nijo......cultivated two-rowed barley, strain No. 144.
2) Each pair of the chromosomes is characterized by its length and shape, and therefore, they are designated as a, b, c, d, e, f and g.
3) Chromosome type of a race or variety is always constant even in the cells of the different plants.
4) Different pretreatment, killing and staining materials do not alter the relative size and form of the chromosomes: when the material was pretreated with some solutions, such as 0.5, 0.75 and 1.0 per cent solutions of chloral hydrate, each of the chromosomes in a haploid set was contracted in equal ratio.View full abstractDownload PDF (930K)
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