Effects of the longitudinal split of the shoot apices of the germinating embryo and the seedling in Sesamum indicum L. upon the development of the first leaf were studied. The incisions were made in the plane running through the first leaf primordia. When the operation was made one day after sowing, the first leaves were almost normal both in shape and position, double-leaf being not formed. Following the operation made two to four days after sowing, the first leaf developed into an odd shape defective of lamina on the cut side. Comparing the leaf blade deficiency caused by the operation with the stages of development of the leaf primordial at the time of operation, the following are evident: when the leaf primordium of the buttress stage is split into two halves, both of them are capable of developing complete leaves; the leaf primordium under apical growth is still partially capable of developing leaf blade when it is split; but after the apical growth is over and the laminal development has begun, the half of the split leaf primordium is no longer potent of blade formation on the cut side. The decrease of the potency accompanying the growth of the leaf primordium is suggested also by the incompletely organized vascular system of the midrib. When the time of operation was delayed the differentiation of the branch bundle on the cut side from the median bundle was omitted. After the operation the vascular bundle was differentiated deep in the center of the midrib, although the procambium must have been laid bare on the cut surface when the leaf primordium was split by the operation.
Paper-chromatographic analysis of anthocyanin occurring in flower, stem and fruit-coat of eggplant showed that Burma, Sendai-naga No. 1, Shin-kuro, Hetamurasaki and Emerald contain an acylated anthocyanin, whose Rf values agreed with nasunin, whereas Black Beauty contains delphinidin 3-glucorhamnoside as major component. Within a single variety, the main anthocyanin proved to be the same one in stem, flower and fruit-coat. The complex anthocyanin of Burma-type was shown to be p-hydroxycinnamoyl derivative of delphinidin 3, 5-diglucoside combined with rhamnose. In the crossing experiment, it was observed that the F1 hybrid between Burma and Black Beauty produced an acylated anthocyanin of Burma-type and in F2 generation Burma- and Black beauty-type segregated in accordance with the simple Mendelian ratio of 3:1. Accordingly, two biochemical characters, i.e. the acylation and glycosidation in anthocyanin molecule are shown to be controlled by a single pair of genes.
The occurrence of gibberellins in the extracts of mature dry seeds from 18 different species of dicotyledonous plants was examined by means of paper chromatography and rice seedling methodGibberellins were evidently found in the seeds of sunflower, head lettuce, ucumber, water melon, towel gourd, dodder, morning-glory, cypress vine, sweet potato, common moonflower, balloon vine, garden nasturitium, yellower lupine, broad bean, and apple, but not in those of tomato, natsudaidai, and Japanese radish The seeds of the Convolvulaceae contained considerably higher concentrations of gibberellins and their contents were equivalent to 0.1-1μg. gibberellin A pergram of dry seed The writer wishes to thank Prof. T. Miwa and Dr. T. Hayashi for their guidance
1) Dwarf and tall strains of Japanese morning glory, Pharbitis Nil Chois., were treated with gibberellin. 2) Differentiation of leaf primordia at the growing point is accelerated by the treatment. 3) The longitudinal diameter of the cells of the treated plants increases than that of the control, and both of radial and tangential diameters of the internodal cells decrease. Gibberellin affected on both cell division and cell elongation and the effects vary in compliance with the age of the treated organs. 4) Cambial activity is ceased almost entirely in the first internode of the treated plant, and the thickening of the cell walls of pericycle and xylem is re- markable. These thick-walled elements are lignified.
Photosynthetic activity and dry matter production during winter were investi- gated in the excised twigs of Sawara cypress Chamaeeyparis pisifera, compared with those in the other seasons. 1. In winter, the chlorophyll content of colored leaves of this conifer, which were brown in appearance, had been reduced by half of that of the leaves remaining in green. 2. Net photosynthetic rate of green twigs in winter was positive, though it was at a low level of one third of summer rate. The colored twigs showed more remarkably depressed net photosynthetic rate, and their light compensation point ascended markedly. 3. A positive productivity of green twigs in winter can be observed only in the case of moderately low temperature; under an optimal condition in winter, it was estimated at 3.1 mg. dry matter/g. fresh weight/day, i. e. about one sixth of summer maximum productivity. The colored leaves could have a productivity of only one fifteenth of the summer value.
In the description of plants some observations from the standpoint of the lifeform were not uncertain. We discussed some of ambiguous types of life-forms in the previous paper (Report II, 1956). After Raunkiaer, “Geophytes include land plants whose surviving buds or shoot-apices are borne on subterranean shoots at a distance from the surface of the ground” (1934, p. 64). On the contrary, “all hemicryptophytes have their surviving buds or shoot-apices situated in the soil-surface” (p. 41), and “the buds do not come above the surface of the ground” (p. 40). The difference between the expressions “at a distance from the soil-surface” and “in the soil-surface” is sometimes very nice, especially in shallow geophytes. We measured as many individuals of doubtful species as possible at different habitats (Figs. 1-10, Tables 1-3). That explains the matter there are variable species such as Desmodium racemosum and Vicia unijuga, and little-variable ones such as Ligularia tussilaginea. In the former a geophyte in a statistical meaning is sometimes like a hemicryptophyte or a chamaephyte as shown in Table 2. And the type of the life-form of species forming a dead centre (Figs. 1-2) is too apt to be misjudged in a season when the clonal connection breaks. The position characteristic of the surviving bud of variable species (Table 2) is considered to some extent as an indicator criterion, but in other plants the value as an indicator is little.
1. The photoperiodic responses of a short-day plant, Salvinia natans, were studied by supplying with the organic acids of citric acid cycle. The acids used were citric, succinic, fumaric and malic acids, added to the culture solution only during the dark period. 2. The developments of the sporocarps were inhibited by the citric acid of all Nov.-Dec. 1959 Bot. Mag. Tokyo, Vol. 72, Nos. 857-858 465 the concentrations tested, while in succinic, fumaric or malic acid of lower concentrations their developments were more or less accelerated, especially by the succinic acid. 3. The inhibiting effect of citric acid on the photoperiodic induction was not found when the other acids were also used at the same time. These facts seem to suggest that the effect of citric acid on a process of the photoperiodic induction was antagonistic with that of the others, though all the acids used were available as the substitutes of carbohydrate required for the development of the sporocarps. 4. The malonic acid combined with the acids other than citric acid made some decreases in the photoinductive effect, whereas it was notably increased when the former acid was used alone. In citric acid, however, no such decreases were observed. 5. These facts seem to indicate that a relative quantity of the organic acids in the plants may be an important factor for an alternation from the vegetative to the reproductive phase.
The spores of 193 strains of Streptomyces were observed with an electron microscope. There are some relationships between the morphology of sporophores classified by Pridham et al and the electron microscopic fine structure of the surface of the spores. The morphological observation with the electron microscope may be available and feasible for the classification of Streptomyces. 1. Shapes of the spores were classified into three groups, namely, spherical, ellipsoidal and cylindrical. These three shapes change continuously. The shape and uniformity of the spores were not constant even in one spore chain. 2. Markings of surface of the spores were classified into such groups as smooth, rough, granular, short-spiny, spiny and hairy. But the present authors could not observe wrinkled spores. 3. It is a remarkable fact that all of the twenty strains which show clear marking of surface of the spores belong to the spira.
1. The present work was carried out to investigate experimentally if the germination percentage and the pollen tube growth are different among various densities of pollen grains put on sucrose agar media. 2. These pollen grains of the following plant species Camellia sinensis, C. japonica, Iris pseudacorus, Lathyrus odoratus and Oenothera Lamarkiana were used for this purpose. 3. The greater the number of the grouping grains became the more the germination percentage and the tube growth increased. The difference of the tube growth was most conspicuous when a single isolated grain was compared with the two grains grouping set side by side. 4. A group consisting of five or six pollen grains secures the best growth of the pollen tube on agar media, whereas more grouping grains are required to gain the best germination percentage. 5. It was discussed that certain substances might take part in the increment of germination percentage and the acceleration of pollen tube growth.