遺伝学雑誌
Online ISSN : 1880-5787
Print ISSN : 0021-504X
ISSN-L : 0021-504X
43 巻 , 3 号
選択された号の論文の7件中1~7を表示しています
  • VI. INTERGENERIC HYBRID BETWEEN EREMOPYRUM ORIENTALE AND AEGILOPS SQUARROSA
    SADAO SAKAMOTO
    1968 年 43 巻 3 号 p. 167-171
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    An intergeneric hybrid between Er. orientale and Ae. squarrosa was reported. The spike shape of the F1 was intermediate between the parents but the spikelets showed the characters of Eremopyrum. In the majority of cells no chromosome pairing was observed. Average chromosome pairing was 0.1II+20.8I. This shows that the genomes of Er. orientale are quite different from the D-genome of Ae. squarrosa.
  • YUKUO YOSHIDA, SHOHACHIRO YUKI
    1968 年 43 巻 3 号 p. 173-179
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    The effects of nitrosoguanidine on Bacillus subtilis were studied. Lethal damage produced by nitrosoguanidine was repairable in the sense that the repair was inhibited by acriflavine. Mutation was induced more efficiently at the initial period of the treatment when the killing effect was not high. The repairable damage seems to have little connection to the potent mutagenic action of nitrosoguanidine. It was also found that less amount of DNA could be isolated from nitrosoguanidine-treated cells, and the genetic linkage was lowered in the DNA isolated from treated cells, as compared with DNA isolated from untreated cells. It was postulated from these results that nitrosoguanidine would produce some unknown damage on DNA or on some other cellular components which would then act to induce mutation at very high efficiency.
  • III. VARIATIONS IN GENERAL SIZE AND ALLOMETRIC PATTERN AMONG MUTANT LINES
    HIROKO MORISHIMA, HIKO-ICHI OKA
    1968 年 43 巻 3 号 p. 181-189
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    The length at maturity of various organs and other agronomic characters were measured in 33 mutant lines radiation-induced from a rice variety, Norin 8, which were selected for high fertility and yield. Principal components were extracted from the genetic correlations of organ length. The first component showed an “isometric” phase of variation (general size), in which various organs varied proportionally in length. The second vector showed a variation in the relative length of organs (“allometry”). In this phase of variation, the organs in a stem sequentially increased or decreased in relative length from the top to the base, bringing about the contrast between “upper- elongation” and “lower-elongation” types. In the same manner as in our previous work on F3 lines, the α (“panicle-number” vs. “panicle-length” type, the former having more but smaller panicles and leaves than the latter) and the β (“internode-length” vs. “internode-number” type, the former having fewer but longer internodes and more erect leaves than the latter) variations in plant type were obtained from the mutant lines, when the data for panicle number and mean internode length were adjusted by the score for general size. The α and β plant-type scores were correlated with the scores showing general size and differential relative size of organs, respectively. Possibly, variations in agronomic characters of cereal crops may be largely conditioned by such an isometric and an allometric factor, the former involving the size-number relationship of stems, and the latter representing sequential change in the relative length of organs in a stem.
  • IV. GENERAL GROWTH RATE, OSCILLATING GROWTH AND ALLOMETRIC PATTERN
    HIKO-ICHI OKA, HIROKO MORISHIMA
    1968 年 43 巻 3 号 p. 191-201
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    Between-line variations in the final size, the time at which half of the final size was attained (t1/2), and the growth rate at t1/2, were studied for the panicle and first to fourth (from the top) internodes. Materials used were 23 mutant lines radiation-induced from a rice variety, Norin 8, which were selected for high fertility and yield. For each of the above three values, principal components were extracted from correlations between the five organs, and the “genetic vectors” showing genetic contributions of the components to the respective organs were computed. In the final size, as reported in our previous paper, two latent phases of genetic variation were distinguished, one showing the general size (isometry), and the other showing an allometric pattern that brought about the variation between “upper-elongation” and “lower-elongation” types. Variations in the growth rate of organs similarly comprised an isometric and an allometric phase. Lines with a generally high growth rate had a large general size at maturity. In the allometric phase, lines whose panicle and third internode elongated relatively slowly had a relatively high growth rate for the first and second internodes. Such lines tended to be the “upper-elongation” types at maturity. As the panicle and third internode elongate some days before the elongation of first and second internodes that results in heading, the allometric pattern of growth rate suggests that the lines vary in the rhythm of development. This was proved by an observation of the change of relative growth rate in the period from panicle elongation to heading. It was suggested that genes modify the rhythm of development and bring about the size variations observed at maturity.
  • SHOJI SHIGENAGA
    1968 年 43 巻 3 号 p. 203-210
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    1. Four kinds of quadruple monosomics and one kind of quintuple monosomics were produced by a systematic procedure in a variety Chinese Spring of common wheat, Triticum aestivum ssp. vulgare.
    2. Quadruple monosomics (17II+4I) were selected in the progeny of the cross between triple monosomics (18II+3I) and a nullisomic, which lacks the fourth pair of chromosomes. The quadruple monosomics were pollinated with pollen grains of a nullisomic, which lacks the fifth pair of chromosomes, and in their F1's quintuple monosomics (16II+5I) were selected.
    3. Quadruple monosomics were more or less smaller in size, and reduced in vigor with somewhat later maturity, but they were fertile in both sexes. Quintuple monosomics were still inferior to the quadruple monosomics in their various characters, though they retained reproductive ability.
    4. Crosses between quadruple monosomics (_??_) and normal plants (_??_) were made to maintain the quadruple monosomic strains; F1's obtained had 38 to 42 chromosomes. The 38-chromosome plants appeared at a frequency of 21.2 per cent, and showed the 17II+4I chromosome configuration at meiotic metaphase I, which indicated that they were quadruple monosomics.
    5. The present results indicated that the female gametes with the least chromosome number in expectation participate at a high frequency in fertilization in every kind of hypoaneuploids, so far produced in hexaploid wheat.
  • 古 庄敏行
    1968 年 43 巻 3 号 p. 211-238
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
    身長を支配する遺伝子型の発現をみるために, 同一個人の発育期から発育完了期までの逐年身長測定資料を用いて分析を試みた.
    1. 発育完了期の年令と発育過程の各年令との間の身長の相関係数 r'i•j は概ね年令間の差が小さくなるにつれて高くなるが, 前思春期の年令に相当して一時的に相関が減じるため, r'i•j-curve の変動は相加的直線的でなく数次曲線に従う (Fig. 1, 2). r'i•j-curve は9つの samples を通じて非常によく類似した傾向を示した.
    2. この r'i•j と年令別年間身長発育量の全国平均との間には強い逆相関 (r=-0.81~-0.97) がみられ, 発育の速かな年令期ほど r'i•j の小さいことがわかった.
    3. Yoshida (1944) の子の年令別身長の親子相関と r'i•j との間に強い相関が存在することを知った (r=0.79~0.88). また, Takiguchi (1945) によって報告された発育完了期の兄と15~19才の弟との年令別身長相関も, 弟の14才以下の資料がないので完全に一致するか否かは確実ではないが, Fig. 1, 2の r'i•j (i=20, 21 in Data 2) に類似の傾向は示した.
    4. このように年令によって親子相関や同胞相関の値が変動することが, 従来の報告においてこれら相関の値に大きな差の見られた原因の1つであると考えられる.
    5. 発育完了期の身長と年間発育量との間の相関 (r'i•jp) を各年令別に求めたところ, 発育の最も速い年令期 (男•10~13才, 女•9~12才) において概ね逆相関を示した.
    6. これらの事実により, 発育完了期の身長を支配する遺伝子型の発現は年令によって異なることと, この発現が前思春期には他の要因によって modify されることがわかる.
    7. 同一年令で比較したときの双生児対偶者間の強い相関は1卵性双生児, 2卵性双生児とも年令とは殆んど関係がなく, ほぼ一定している. Otuki (1956) が報告した, 同一年令で比較した親子間の身長相関も, 年令による変動を示していない. このことは, 身長発育の pattern もまた遺伝子型の支配を受けることを示すもので, この遺伝子型は発育完了期の身長を支配する遺伝子型とは, かなり独立であると考えられる.
    8. 従って, 身長に対する近親婚, 放射線などの遺伝的影響を研究するには, 発育の全過程を通じての観察にもとづくことが望ましい.
  • SOHEI KONDO, HARUKO ICHIKAWA
    1968 年 43 巻 3 号 p. 239-240
    発行日: 1968年
    公開日: 2007/05/21
    ジャーナル フリー
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