日本産ラン科植物の染色体数(第 4 報)(A. 理学)

Chromosome counts are made for 6 species, one forma and one variety in 8 genera of the family Orchidaceae in Japan. Preparations were made from root tips or buds by the modified squash method (Mutsuura & Nakahira, 1956). Chromosome numbers of Listera nipponica, Goodyera hachijoensis var. leuconeura, Oberonia Japonica forma major, Tipularia japonica, Liparis formosana, Phajus Tankervilliae and Bulbophyllum Makinoanum are reported for the first time, and the number of Calypso bulbosa is reconfirmed (Table 1)

日本産ラン科植物の染色体数(第 3 報)(自然科学)

Chromosome counts are made for 17 species of the family Orchidaceae in Japan. Preparations were made from root tips by the modified squash method (Mutsuura & Nakahira, 1956). Chromosome numbers of 14 species are reported for the first time, and those of 3 species are reconfirmed (Table 1,Figs. 1-2,Plate 1). We have found the 2n nu-nbers 18,20,24,46,48,56,60 and 64 in the Orchidaceae in Japan. Chromosome numbers of Habenaria Miersiana, Dendrobium moniliforme and Cymbidium virescens are different from those reported previously (Table 1)

K-培地に関する研究 : ブドウ球菌および大腸菌の発育とその電子顕微鏡的観察(B. 生活科学)

K-medium is a new type of culture media developed by Katsuya in 1956.^ This inorganic medium is prepared from sodium silicates and phosphoric acid. The advantage of this medium is that it turns to a gelatinous form without heating. In order to evaluate the applicability of K-medium for practical use, growth and ultra structure of Staph. aureus and E. coli grown on this medium were studied comparing with of those grown on Agar-medium. The results obtained are as follows : 1) Number of colonies on K-medium of Staph. aureus and E. coli were significantly increased compared with those on Agar-medium. 2) Ultra structure of Staph. aureus and E. coli cultivated on both media were not differ much from one another. The above results suggest that the K-medium may be useful for detecting contaminations of Staph. aureus and E. coli of foods

アフリカツメガエル卵母細胞を用いるタンパク質生合成のための簡易微量注入法(農芸化学部門)

アフリカツメガエル卵母細胞へのRNA, DNA等の細胞成分注入用の簡易な微量注入装置を考案, 試作した。この装置を用い特に植物性mRNAをアフリカツメガエル卵母細胞へ注入しタンパク質生合成を行わせた。その結果, tobacco mosaic virus RNA, brome mosaic virus RNA, イネglutelin前駆体mRNA, エンドウriburose 1,5 bis-phosphate carboxylase mRNAが忠実に翻訳され, 対応するpolypeptideが形成されることをsodium dodecyl sulfate polyacrylamide gel電気泳動(SDS-PAGE)による分子量の測定と免疫学的方法を組合わせることにより確認した。A simplified and convenient microinjection system to inject cell components such as DNA and RNA into Xenopus oocytes was devised and constructed. By use of this system, RNAs of plants were injected into Xenopus oocytes, then their protein syntheses were examined. Tobacco mosaic virus RNA, brome mosaic virus RNA, rice glutelin precusor mRNA, and pea Riburose 1,5bisphosphate carboxylase mRNA were faithfully translated. The nature of the synthesized polypeptide was confirmed by fluorography using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoelctrophoresis

Taeniophyllum aphyllum (MAKINO) MAKINO に関する研究発芽及び幼植物の発育過程について(A. 自然科学)

In Kyoto, Taeniophyllum aphyllum (MAKINO) MAKINO is found to be growing on the trunks of several kinds of trees, especially on the underside of the branches of Cryptomeria Japonica. This orchid has several morphological characteristics unseen in other orchids. The young plant is a leaflike body and it grows very slowly. Observation was made on the growth of the young plants growing on the branches, especially, the earlier stage of the development was compared with that of the seedlings growing on a culture medium. The young plants grows to about 0.5mm in length in one year after germination, 1mm in 2 years, 1.8mm in 3 years, 2.9mm in 4 years, 4.5mm in 5 years, 7mm in 6 years, 9-12mm in 7 years, then the first root and the reduced leaf emerge at the end of the leaflike organ. This organ gradually shrinks and dies off after bearing about 7 roots. From the observation of tissues, it is assumed that the young plant of 3-7 years old is composed of a mixture of cotyledon and hypocotyl tissues

Primula malacoides FRANCH. の細胞学的研究(数学及び自然科学)

17 garden varieties and their offsprings of Primula malacoides were studied cytologically. 13 varieties are found to be tetraploids, and 4 varieties, garden primroses cultivated from old, to be diploids (2n=18), and one to be a triploid (2n=27) (Table 1,Fig. 1). In meiosis of tetraploids 18II are shown, but pairing of bivalents is incomplete in general, and separation at anaphase is irregular in some varieties. Some of tetraploid offsprings are found to be aneuploids, somatic numbers being 34,35,37,38 and some of them have abnormal chromosomes (Table 2,3,Fig. 2). These offsprings are dwarf or male sterile, or have abnormal petals. So some of tetraploid varieties are assumed not to be genetically pure. Diploid varieties, on the other hand, exhibited regular meiosis, and chromosome numbers of their offsprings are normal. Triploid plants are found in the cross tetraploid×diploid