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Volume 21, Issue 1
Displaying 1-11 of 11 articles from this issue
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J. M. J. de Wet, L. J. Anderson1956Volume 21Issue 1 Pages 1-10
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSThe genera investigated were classified according to Pilger and the position of the tribes Arundinelleae, Phyllorachieae, Stipea and Aristideae in this system of classification was critized. The chromosome numbers of 79 species belonging to 45 genera have been counted. Fifty-seven of these species were recorded for the first time, or chromosome numbers differing from earlier counts were reported. The following genera were previously unknown cytologically: -Schnzidtia (n=9); Phyllorachis (n=12); Bewsia (n=10); Miscanthidium (n=10); Urelytrur (n=10); Chrysopogon (n=10) and Trachypogon (n=10). The inclusion of the genus Ehrharta in the tribe Phalarideae was criticized. It was suggested that this genus should be transferred to the tribe Oryzeae, It was also pointed out that the genus Trtrachne belongs in the Eragrosteae.View full abstractDownload PDF (651K) -
T. Haga, T. Ogata1956Volume 21Issue 1 Pages 11-20
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSDownload PDF (588K) -
I. Syncytes in certain clones of Saccharum and ErianthusSam Price1956Volume 21Issue 1 Pages 21-37
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESSLarge multinucleate and polyploid P. M. C.'s (syncytes) were observed in Erianthus arundinaceus, in Saccharum robustum, and in a S. sinense×spontaneum hybrid. Further development of these syncytes was traced as far as possible through meiosis.
Syncytes previously reported in plants are classified according to whether they originated through errors in archesporial mitotic divisions, through the migration of a nucleus from one P. M. C. into another, or through the fusion of P. M. C.'s. The syncytes described in Saccharum and Erianthus are con-sidered to be cases of fusion syncyte formation.
It is suggested that in Saccharum and its relatives, syncytes might lead to the formation of diploid pollen grains, and that they may play a part in the male transmission of 2n chromosome numbers.View full abstractDownload PDF (2602K) -
Hidejiro Niiyama1956Volume 21Issue 1 Pages 38-43
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESS1. The spermatogonium contains 63 chromosomes. In the serial alignment of the paired chromosomes a single V-shaped chromosome of outstandingly large size remains unpaired. The chromosome constitution of the spermatogonium comprises 62 autosomes and an X-element.
2. At diakinesis the X-chromosome appears as a heteropycnotic body.
3. The primary spermatocyte metaphase always shows V-shaped X-chromosome migrating precociously to one of the poles.
4. Some of the secondary spermatocytes contain an X-chromosome of large V-shape.
5. On the basis of the above facts, it is apparent that the present species shows male heterogamety represented by an X-O mechanism.View full abstractDownload PDF (1038K) -
Hiko-Ichi Oka, Chen-Hui Kao1956Volume 21Issue 1 Pages 44-49
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
JOURNAL FREE ACCESS1. The number of nucleoli newly formed in somatic telophasic nuclei was observed in a number of rice varieties from various Asian countries.
2. In some varieties, the number of nucleoli varied from two to four from cell to cell, while in other varieties two nucleoli were found in all cells. The former and the latter varieties may correspond to the so-called “quadrinucleolar” and “bi-nucleolar” types.
3. About two thirds of the “Continental” varieties and a half of the “Tropical-Insular” varieties were of quadri-nucleolar type. In the former, the mean number of nucleoli ranged from 2.2 to 3.6.
4. All Japanese lowland Varieties were of bi-nucleolar type, while both bi- and quadri-nucleolar types were found in different proportions in other regions.
5. It was mentioned that rice might have two pairs of nucleolar chromosomes, and the nucleolus-forming power of the second pair being relative to the first, as shown by the mean number of nucleoli, might vary continuously among varieties.View full abstractDownload PDF (355K) -
H. W. Beams, Everett Anderson, Newtol Press1956Volume 21Issue 1 Pages 50-57
Published: March 30, 1956
Released on J-STAGE: March 19, 2009
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