巻号一覧
26 巻, 5-6 号
選択された号の論文の8件中1～8を表示しています
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Humihiko Ono1951 年 26 巻 5-6 号 p. 157-173
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリー1. Many F4 individuals of Paraixeris denticulata×Crepidiastrum platyphyllum were studied both morphologically and cytologically with special reference to their fertility.
2. In many individuals the somatic chromosome number was 10. Only three had 11 chromosomes. The mechanism of preservation of the chromosome number was supposed to be well equipped.
3. In the root-tips of four individuals, polyploid cells were observed beside the diploid ones. The tendency of chromosome doubling in heterozygocity seems not to be unusual.
4. In many individuals new types of chromosomes were observed. This seems to be a similar phenomenon to the novation of Navashin, and seems to be caused by semihomologous crossing-over.
5. In the meiotic division some individuals had only bivalents. But in the others multivalents or prematurely separating bivalents were observed in abundance. The forms and the components of multivalents were quite variable. In general more multivalents were observed in the earlier diakinesis than in the metaphase. From the observations of meiosis the following conclusions have been drawn.
a) Winge's hypothesis of systematic importance of polymery may be applied also to the explanation of chromosome pairing.
b) A hypothesis of residual affinity in pairing advanced by the present author explains adequately the various configurations observed.
c) The secondary association may be a manifestation of residual affinity.
6. There were little correlation between the pollen fertility and the rate of achene setting (r=0.20). The low pollen fertility was correlated with the multivalents and the low rate of achene setting with the prematurely separating bivalents. It was supposed that the mode of meiosis is different in male and in female, and that the pairing power is a little stronger in female.
7. The fertility was much restored in F4 in spite of an increase of meiotic irregularities. This seems to be caused mainly by the restoration of cytoplasm-nucleus relations. It was suggested that the alteration of cytoplasm in accordance with the foreign nucleus will be taken place gradually both in somatic and germ cells.
8. The inclination of F4 population to the type of Paraixeris parent was supposed to be the consequence of selection pressure of the cultural conditions. It is remarkable that new intermediate forms with higher fertilities have appeared.抄録全体を表示PDF形式でダウンロード (1733K) -
木村 資生1951 年 26 巻 5-6 号 p. 175-184
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリー1) 近年におけるキアズマ型説の進展と, 下等生物に対して行われた四分子析の研究とは染色体上の各遺傳子が還元分裂に夫々一定の確率で前減数及び後減数を行うことを明らかにした。然し染色体全体としての減数の状態を知る爲には更に統計学的理論を必要とする。
本論文においては次の2つの問題を論じた。
(a) 與えられた染色体について, 前減数及び後減数を行う染色体部分の長さの頻度分布を求めること。
(b) 遺傳学的に良く研究されている種々の染色体について前減数及び後減数を行う平均の長さを明らかにすること。
2) 1端に附着点を有し, 染色分体干渉の存在しない長さ 100l 單位の染色体に対しては, 後減数を行う長さ (ξ) の頻度分布は次の式で與えられる。
Φ(ξ)=φ′(ξ)+2φ′(l-ξ)-(l-ξ)φ"(ξ)-1
ここに φ(ξ) は100單位隔れた2遺傳子間の組換確率であり, 式の導出に際しては3交叉以上の多交叉は頻度において無視し得るものとしてある。
猩々蠅のX染色体 (70單位) に対しては上式は
Φ(ξ)=cos2ξ+2cos(1.4-2ξ)+(1.4-2ξ)sin2ξ-1
となる (第2図)。
3) 染色体をX軸上にとり, その上の点 x の後減数を行う確率を f(x) とすれば, その染色体又は染色体部分 ab の後減数を行う平均の長さは
L=∫baf(x)dx
で與えられる (第6図)。
4) 遺傳学的に詳細に研究された染色体について, 前減数及び後減数を行う長さ (l-L, L)の全長に対する割合 (即ち l-L/l 及び L/l を%で表わすと次の如くである。
l-L/l L/l
Neurospora crassa 性染色体 66.5% 33.5%
Sphaerocarpus Donnellii, squamifera- 染色体 52.2% 47.8%
猩々蠅, X 染色体 { 46% 54% 48%※ 52%※
仝 第 II 染色体 48% 52%
黒猩々蠅, X 染色体 { 40.7% 59.3% 40.0%※ 60.0%※
ここに※を附した値は細胞学的染色体地図を尺度としたもので, それ以外の値は遺傳学的地図を尺度としたものである。抄録全体を表示PDF形式でダウンロード (5392K) -
I. 遺傳子分析山田 豊一, 藤吉 清次1951 年 26 巻 5-6 号 p. 185-194
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリーThe inheritance of the types of young plants which are prominent at the younger stage of development in wheat has been studied, with particular reference to some of the adult characters, in 4 successive generations from F1 to F4 of Hokuriku No. 13 with Saitama No. 27 crossing from 1938 to 1941.
The types of young plants were classified into five or six classes, T1-T5 or T6, from prostrate to erect by observation (c. f. Fig. 1).
The young plant type was intermediate in F1 between both parents. The distribution curve on the plant types of 390 F2 plants fairly resembled a normal curve as shown in Table 1. In 110 F3 lines descended from each class in F2 generation, various mean values (Type-values), which express the types of young plants in each line numerically, were observed as shown in Table 3. The result may be explained by two heteromeric major genes E1 and E2, which are imperfect in dominancy (c. f. Table 4-6 and Fig. 2).
In F4 generation, however, 17 families derived from each of 9 genotypes in F3 generation were grown, and the segregation was found more complicated than in F3 (c. f. Table 7). From this result it was assumed that the third gene E3, the effect of which being considerably weaker than the former two, should concern to the genic constitution of the young plant types. All F4 lines were successfully classified into 27 genotypes, which should theoretically result from the segregation of the three gene pairs (c. f. Table 8-10).
It may be concluded, therefore, that the types of young plants are controlled by three major heteromeries.抄録全体を表示PDF形式でダウンロード (1623K) -
北田 仁一1951 年 26 巻 5-6 号 p. 195-197
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリーSeasonal spermatogenetic changes were observed in the testis of a lizard, Eumeces latiscutatus, common in Japan-Hondo. During the months of April, May and early June, all spermatozoa are eliminated from the seminal tubules. Spermatogonial divisions occur in May and June. Primary and secondary spermatocytes and maturation divisions appear through July and August. Spermioteleosis is practically completed during from late November to December. During hibernation, there is no spermatogenetic activity in the testis.抄録全体を表示PDF形式でダウンロード (318K) -
II. B. 2n=44染色体を有する F1 植物の花粉母細胞成熟分裂中島 吾一1951 年 26 巻 5-6 号 p. 199-202
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリー1. 小麦ライ麦三元雜種 (T. turgidum×S. cereale)×T. vulgare F1 の中, 2n=44染色体を有する個体の花粉母細胞成熟分裂について細胞学的研究を行つた。
2. この個体は 2n=23 染色体を有する T. turgidum×S. cereale F1 と T. vulgare との雜種である。
3. 2n=44 染色体の中21は T. vulgare から, 残りの23は第一次雜種, T. turgidum× S. cereale F1 に由來するものである。
4. 花粉母細胞第一成熟分裂において2價染色体数は4～12, 1價染色体数は20～36である。
5. 花粉母細胞成熟分裂研究の結果から見て, この植物のゲノム構成はAB(T. turgidum) +(R+2) (S. cereale)+ABD(T. vulgare) であると考えられる。抄録全体を表示PDF形式でダウンロード (369K) -
中島 吾一1951 年 26 巻 5-6 号 p. 203-209
発行日: 1951年
公開日: 2007/05/21
ジャーナル フリーCytogenetical studies on the amphidiploids raised from interspecific hybrids of Quamoclit by the colchicine treatment have been carried out by the author.
In amphidiploids, the length of guard cells of stomata is larger than that of the parents, and about as large as that of Q. Sloteri (Table 3).
Further, the size of flowers is larger than that of the parents (Fig. 2).
In F1 plants, abortive pollen grains were observed in exceedingly higher percentage than in amphidiploids (Table 5). The size of pollen grains in amphidiploids is larger than that of the F1 (Table 6), i. e., nearly equal in size to the Q. Sloteri's.
F1 plants were completely sterile, but the amphidiploids were fertile, though the percentage is low (16.04%).
The fruits of amphidiploids were morphologically intermediate between parents of them.
The weight of 1000 seeds of Q. coccinea, Q, coccinea var. hederifolia and Q. pennata were 11.6, 14.2 and 16.5grs respectively. And that of the amphidiploids from hybrid I and II were 30.1 and 32.6grs, that is nearly equal to the seed weight of Q. Sloteri, 31.6grs.
The number of somatic chromosomes were 30 in Q. pennata (Fig. 7). 28 in both Q. coccinea and Q. coccinea var. hederifolia (Figs. 5 and 6). In F1 plants of Q. coccinea×Q. pennata and Q. coccinea var. hederifolia×Q. pennata, the number of chromosomes was 2n=29 (Figs. 8 and 9) in both cases. The number of chromosomes of amphidiploids raised from hybrid I (Q. coccinea×Q. pennata) and II (Q. coccinea var. hederifolia×Q. pennata) was 2n=58 in both combinations (Fig. 10). These numbers correspond to double the somatic number of F1 of hybrids I and II, viz. equal to the number of Q. Sloteri's chromosomes 2n=58 (Fig. 11).抄録全体を表示PDF形式でダウンロード (1424K) -
松村 清二1951 年 26 巻 5-6 号 p. 211-218
発行日: 1951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 (17998K) -
今村 昌一1951 年 26 巻 5-6 号 p. 219-222
発行日: 1951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 (596K)
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