1. A large amount of glutathione is contained in the plumule and cotyledons of Nelumbo nucifera. 2. The amount of total glutathione in the maturing Nelumbo seed increases gradually. The reduced form is predominant in early stages, while the amount of oxidized form exceeds that of the reduced form on the end of maturation. 3. The amount of glutathione in the germinating Nelumbo seed increases rapidly and the rate of increase is larger in the reduced form than in the oxidized form. 4. The amount of reduced glutathione in the unripe Nelumbo fruit decreases remarkably upon storage for one year. Such is also the case with the ripe seeds of various other plants. 5. In the ripe fruit of Nelumbo, the amount of glutathione shows not so much change during six years' storage. 6. In general, the rate of germination of the stored plant seed seems to be intimately related to the content of the reduced glutathione.
An attempt has been made to analyse the phenomenon that Epilobium seeds are brought into germination by the repetition of short irradiations (intermittent irradiations) as well as by a long irradiation. The same analysis has proved that intermittent irradiations are also effective for the germination of the seeds of Hypericurn, etc., which have been presumed to germinate only by a prolonged irradiation. In intermittent irradiations, the optimum length of intervals between individual irradiations was found to be about 9 hours both in Boenninghausenia and in Epilobium seeds, while it was longer than 24 hours in Veronicastrum seeds. An interval longer than 9 hours results in an appreciable decrease in stimulating effect in Boenninghausenia and Epilobium seeds. This is likely due to a mechanism common in the case of photoperiodic floral initiation. Rumex seeds are capable of germination by a single short irradiation, while seeds of Epilobiur, HyperZcum, etc. require intermittent irradiations or a prolonged irradiation for their germination. The difference in both types of seeds is considered to be ascribed to the variation in the relation between a required volume of dark reaction or reactions coupled with the light reaction and a volume of one dark reaction which is attained after a single short irradiation.
1) Two species and a variety of Japanese Ophioglossum were examined cytotaxonomically and the systematic position of Ophioglossales was discussed. 2) O. vulgatum showed 240 distinct gametic chromosomes without exception. 3) Four cytological races were found in O. petiolatum. Materials from four populations, Narita c, Usui, Nikko and Choshi, have n =480, and those from Inage, n=510-520. Very irregular meiosis was observed in materials from three populations, Toke, Togane and Kyoto. Those from Toke and Kyoto probably have 2n =ca. 960, while Togane material may have 2n=ca. 1100. 4) Two cytological races were found in O. thermale var. nipponicum. Apparently 480 bivalent chromosomes were counted in the material from Narita d population. The materials from Narita e and Kyoto show irregularity in meiosis, but their somatic chromosome number was estimated to be about 960. 5) No correlation between chromosome number and form of plant was found in comparing each cytological race, even in the very polymorphic species, O. petiolatum. 6) Ninan's suggestion that the primary basic chromosome number of Ophioglossales may be 15 was verified. 7) Section Vulgata is considered a more modified derivative than Aitchisonii in view of chromosomal constitution, since the latter shows no such chromosome numbers as high as 240, 480, 630, etc. 8) In respect of spores O. vulgatum and O. petiolatum can be discriminated easily, no matter how they resemble each other in cytological and morphological features. 9) Ophioglossales is considered a very specialized group far apart from other modern ferns, phylogenetically. The authors wish to express their cordial thanks to Mr. T. Namegata, President of Nippon Fernist Club, for providing many materials for the present study.
1. The changes in amount of gibberellin-like substances in ripening seeds and developing seedlings of a tall variety, “Tendan”. and a dwarf variety, “Kidachi”. of Pharbitis nil were investigated. 2. The amount of the gibberellin-like substances in the seed of “Tendan” increased during the ripening process and reached a maximum on the 20th day after anthesis. The amount of these substances in the seed of “Kidachi” increased slowly, and reached a maximum about 10 days after anthesis. The maximum amount of the substances in “Kidachi” was one-sixth that in “Tendan”. 3. Both in the cotyledon and in the hypocotyl of seedlings grown in dark or light, the amount of gibberellin-like substances was greater in “Tendan” than in “Kidachi”. In the dark, the maximum amount of the substances in the cotyledon of “Tendan” was about two times, and in the hypocotyls more than ten times, greater than those in “Kidachi”. 4. It seems highly probable that the growth habit of the dwarf mutant, “Kidachi”. is due to the low content of endogenous gibberellin-like substances.
1. In red and white varieties of both radish (Raphanus sativus) and turnip (Brassica rapa), comparative analyses were made chromatographically on the contents of free amino acids, sugars and phenolic acids throughout the growing stage. 2. In four kinds of plant materials examined, four kinds of free sugars are present in common. Among them, glucose is a major component throughout the growing stage. Some quantitative difference may be noted in that both sucrose and fructose are present in larger quantity in the red root than in the white. 3. Seven kinds of phenolic acids are detected in all plant materials examined. Most of them are in a 'bound' form. The total amount of acids is larger in the red root than in the white one. 4. In red roots, the amount of C6-C3 acids increases gradually in parallel with the progress of anthocyanin synthesis. 5. Eighteen kinds of free amino acids are common to the roots of all plant materials examined. The percentage of individual amino acids to the total was higher in valine, leucine, arginine, (methionine), asparagine and glutamine in white roots, whereas the values for aspartic acid, glutamic acid and tyrosine are higher in red roots. 6. In red roots, sugars and amino acids decrease in amount temporarily at a time of rapid anthocyanin formation. 7. Anthocyanin production in the seedlings of the red varieties is stimulated by the administration of several amino acids such as leucine, phenylalanine and valine, and also by aspartic acid and threonine.
This paper deals with the results of the karyological studies on seventeen moss species belonging to the family Thuidiaceae. In the karyological studies, metaphase and heteropycnotic chromosomes in mitotic cells of gametophyte were observed. In sixteen species of the family, excluding Tetracladium molkenboeri (n=22), the same chromosome number, n =11 was counted. The karyotypes of these sixteen species were so much alike with each other that they were represented by the same karyotype formula. The karyotype formulae of the seventeen species are as follows: Haplohymenium pseudo-triste H. sieboldii H. triste Herpetineuron toccoae Claopodium aciculum C. assurgens C. gracillimum C. nervosum C. pellucinerve Haplocladium microphyllum H. strictulum H. subulaceum Thuidium bipinnatulum T. cymbifolium T. glaucinum T. kanedae}K(n)=11=V(H)+V+J+7(5v+2j)±m(h) Tetracladium molkenboeri……K(n)=22=2V(H)+2V+2J+14(10v+4j)+2m(h).
1. Root nodules and root tips of nine leguminous species in four genera, Vicia, Lathyrus, Pisum (Tribe Vicieae) and Trifolium (Tribe Trifolieae) were studied cytologically. 2. Same chromosome number was found in both root nodules and root tips of Viciafaba. It was the first finding in plant species that there were root nodules having only diploid cells. 3. Tetraploid cells were common in root nodules of the other eight species studied. In some species, however, few diploid cells and very few octoploid cells were observed in root nodules. 4. No aneuploid cell was observed in root nodules of all species studied. 5. It was found in each of nine species that the karyotypes of diploid or tetraploid cells in root nodules were similar to those of root tip cells, thus indicating no morphological aberration of chromosomes in root nodules.