巻号一覧
41 巻, 3 号
選択された号の論文の9件中1～9を表示しています
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III. PENTAPLOID AGROPYRON HYBRIDS AND GENOMIC RELATIONSHIPS AMONG JAPANESE AND NEPALESE SPECIESSADAO SAKAMOTO, MIKIO MURAMATSU1966 年 41 巻 3 号 p. 175-187
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーCytogenetical studies of eight interspecific pentaploid hybrids among five Japanese and two Nepalese species of Agropyron are reported.
(1) The general characteristics of F1 hybrids were either intermediate between the parents or superior to those of the parent and (2) the hybrids were completely sterile.
From chromosome pairing of F1 hybrids, it was observed that the two genomes of three Japanese tetraploid species, Ag. ciliare, Ag. gmelini and Ag. yezoense, are identical with the corresponding two genomes of Japanese hexaploid species, Ag. humidum and Ag. tsukushiense. Two genomes of Nepalese tetraploid species, Ag. gmelini and Ag. semicostatum, are basically homologous with those found in Japanese species but some chromosomal differentiation must have taken place between Japanese and Nepalese genomes.
Summarizing the results obtained from tetraploid and hexaploid hybrids in the previous paper (Sakamoto and Muramatsu 1966) and the present results from pentaploid hybrids, genomic interrelationships in Japanese and Nepalese species were discussed. Genome formulae for three tetra- and two hexaploid Japanese species, and two tetraploid Nepalese species are given in Table 7.
Cytogenetical studies between Japanese and Nepalese species provide experimental evidences of genomic differentiation by geographical isolation, lasting a long time, of closely related species which are distributed in the same phyto-geographical area, the Sino-Japanese Region.抄録全体を表示PDF形式でダウンロード (2699K) -
IV. NATURAL HYBRIDIZATION AMONG JAPANESE AGROPYRON SPECIESSADAO SAKAMOTO1966 年 41 巻 3 号 p. 189-201
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーTwo cases of natural interspecific hybridization in Japanese Agropyron were observed in Misima. One is a pentaploid hybrid between Ag. ciliare and Ag. tsukushiense, and the other is a hexaploid hybrid between Ag. humidum and Ag. tsukushiense.
The pentaploid hybrid was highly sterile and no seed setting was observed. It is assumed that in this hybrid combination introgressive hybridization would not occur in natural conditions.
As to the hexaploid natural hybrid, two cases were observed; i.e., one allopatric and the other sympatric. In the allopatric case Ag. humidum and the common type of Ag. tsukushiense were involved, while in the sympatric case Ag. humidum and the early ecotype of Ag. tsukushiense were the parental species. In both cases low seed setting was found from the examination of a considerable number of hybrid clones in natural conditions. From progeny tests of backcrossed plants obtained from the sympatric natural hybrids between Ag. humidum and the early ecotype of Ag. tsukushiense, the following conclusions are drawn: It is quite possible that introgression of characters, such as waxiness, from one species to the other was taking place in the natural populations through backcrossing to the parental species of the F1 hybrids followed by segregation of the characters concerned. Rather quick restoration of fertility in the hybrid progenies made possible the establishment of hybrid swarms in a state of nature having intermingled characteristics of the parental species. However, so far no introgressants have been found yet in the natural sympatric populations of these two species. High sterility of F1 hybrids might be a major cause of restricted introgression.抄録全体を表示PDF形式でダウンロード (1958K) -
BREEDING OF BAKERS' YEAST-DETERMINATION OF THE PLOIDY AND AN ATTEMPT TO IMPROVE PRACTICAL PROPERTIESNORIO GUNGE1966 年 41 巻 3 号 p. 203-214
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーThe occurrence of tetraploidy in bakers' yeasts was demonstrated by the tetrad analysis of mating type alleles and by the determination of cell-size and cell-weight. It was suggested that the growing behavior of cells, e.g. the cluster-formation, may be related to heterozygosity or homozygosity of mating type alleles rather than to the ploidy. The rate of fermentation of given yeasts in dough and in flour free medium is considered to be under control of a heterozygous genetic constitution, in view of the variation in characters among segregants and among hybrids. In crossing experiments, the characters of hybrids and their segregants proved to be statistically parallel to those of component maters prior to crossing, although accompanied by the unexplainable phenomenon that the rates of fermentation of component maters in dough containing a high concentration of sucrose were reduced when combined in hybrids. “Selection and crossing” is an instrument useful for improvement of the practical characters of yeasts. By this method, the rate of osmo-resistant fermentation was considerably increased over the value of the parent. RD yeasts were extremely low in osmo-resistant fermentation.抄録全体を表示PDF形式でダウンロード (1160K) -
NORIO GUNGE1966 年 41 巻 3 号 p. 215-223
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーFrequent production of RD segregants was observed in the asci of tetraploid bakers' yeasts. With the intention of elucidating this phenomenon, genetic analysis was attempted. It was demonstrated that the respiration of the given bakers' yeasts is controlled by at least three complementary genes (tentatively denoted as R1/r1, R2/r2 and R3/r3). Heterozygous conditions containing many recessive alleles and segregation of them may account for the peculiar phenomenon in question. RD yeasts due to mutation of each of these respiratory genes were found to be characterized by a loss or instability of the cytoplasmic factor necessary for respiration. In other words, it was confirmed that the presence of the cytoplasmic factor in the yeasts concerned is stable by the existence of dominant genes, R1, R2 (indispensable) and R3.抄録全体を表示PDF形式でダウンロード (930K) -
池内 達郎1966 年 41 巻 3 号 p. 225-232
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリー1. HeLa 及びL細胞の混合培養を行い, 両系の相互作用を細胞学的に調査した.
2. 両細胞を等量ずつ同時に混合すると約1ケ月以内に混合細胞集団よりL細胞は消失し, 全集団は HeLa 細胞に置き換わる. 混合培養初期には小円型で濃染し, あるいは細胞表層に突起を有するなどの異常形態を示すL細胞が多数観察された.
3. 隔時混合実験においては, 細胞集団内のL細胞の消失は, 同時混合の場合より速く, 形態的に異常な細胞は見られなかった.
4. これらの実験結果より, 培養における異系細胞による cell contamination の問題について, 二, 三の考察をした.抄録全体を表示PDF形式でダウンロード (2146K) -
TAKASHI ITO, MASAHARU DOMON, TERUTOSHI YAMASAKI1966 年 41 巻 3 号 p. 233-240
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーUV induced adenine-requiring mutation in yeast cells was investigated quantitatively at several wavelengths of monochromatic UV and at maximum photoreversion conditions in the hope of elucidating the nature of mutagenesis. The results may be summarized as follows:
(1) In general, mutant production by UV and the remaining mutant, after subsequent treatment by VL at maximum photoreversion, both increased almost linearly against the UV dose, irrespective of the wavelengths used except for some deviation in the shorter wavelengths.
(2) Photoreversible and non-photoreversible fractions of the induced mutaion were determined by taking the ratios of the above two slopes.
(3) Using a scattering factor of UV at the cell boundary, reliable absolute cross sections of the mutation were obtained for the several wavelengths.
(4) Some implications of the above findings were discussed with special reference to the relation between mutation production and the inducible photochemical changes in DNA bases by UV.抄録全体を表示PDF形式でダウンロード (830K) -
TAN TAKAYANAGI, SHOZO INOKI, KATSUMI YOSHIKAWA1966 年 41 巻 3 号 p. 241-246
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーIt was found that the members forming a pair between killer and sensitive cells failed to complete further sexual process, because of the loss of adhesive ability in sensitive cells due to a poisonous substance liberated into the medium from killer cells. Evidence was presented for the intraclonal union in a certain clone of P. polycaryum. Some comments were given on the mating reaction and on the intraclonal union.抄録全体を表示PDF形式でダウンロード (1633K) -
YOSHINOBU SUGINO, AKIKO SORAI, TOKIO KOGOMA, YUKINORI HIROTA, REIJI OK ...1966 年 41 巻 3 号 p. 247-249
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーPDF形式でダウンロード (206K) -
石津 純一, 小関 治男, 三宅 端, 由良 隆1966 年 41 巻 3 号 p. 250-251
発行日: 1966年
公開日: 2007/05/21
ジャーナル フリーPDF形式でダウンロード (420K)
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