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Volume 73, Issue 860
Displaying 1-7 of 7 articles from this issue
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IV. Further Studies on the Light Preceding the Inductive Dark PeriodAtsushi TAKIMOTO, Katsuhiko IKEDA1960 Volume 73 Issue 860 Pages 37-43
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESS1) Five minutes of red light of 3000erg/cm. 2/sec. given at the 2nd to 4th hour of a long dark period does not inhibit flower initiation, but that given at the 8th hour does so.
2) Eight-hour daylight fluorescent light of 10lux (FL) preceding the dark period inhibits flower initiation a little when the dark period is 16hours or more, but promotes when the dark period is 12hours or less. Red light of 5minutes following the 8-hour FL inhibits flowering response strongly irrespective of the duration of darkness. Probably, the red light has a light-break effect, because the first process of the inductive dark period is considered to proceed under the FL.
3) Eight-hour FL mixed with far-red light of 120 erg/cm. 2/sec. (FL+FR) preceding the dark period inhibits flower initiation if the dark period is 14-16 hours, but promotes if the dark period is 10hours or less. The red light of 5minutes inserted between them reduced the flowering responses when followed by a dark period of 14hours or less, but increased flowering to some extent when followed by a 16-hour dark period.
4) Red light following the FL+FR is considered to have a dual effect:
i) It reverses the flower inhibitory effect of FL+FR preceding the inductive dark period.
ii) It has a light-break effect, i.e. a flower inhibitory effect, through counteracting the first process of the inductive dark period, a process which presumably proceeds under FL+FR. The observable effect of red light following FL+FR depends on which effect is the stronger.View full abstractDownload PDF (763K) -
Narumi WATANABE1960 Volume 73 Issue 860 Pages 44-50
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESS1. When Sprillum japonicum is cultured in a medium, it has two kinds of vegetative cells: one type has many conspicuous undulations and forms an exocyst, the other is shorter in length and looks like a rod-bacteria having a slight undulation and forms an endocyst.
2. The organisms of the first type with “conjunction capsule” growing at the extremities form a radiate arrangement. This phenomenon is the cellular fusion which should be assumed as a kind of conjugation. 50 Bot. Mag. Tokyo Vol. 73
3. The protuberance absorbing the protoplasm of each fused cell develops into a globular exocyst. Both the endocyst and the exocyst are deposited motionless in the medium as precipitate. The protoplasm in resting stage in the cyst displays itself as the spiral structure before germination. A new organism grows out of the cyst as the unipolar germination.
4. The life cycle of Spirillum japonicum is indicated in the diagram.View full abstractDownload PDF (2646K) -
Plasmolysis Pattern in Coccophora Eggs.Singo NAKAZAWA1960 Volume 73 Issue 860 Pages 51-54
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSAs a result of plasmolysis experiments in eggs of Coccophora Langsdorfii, the
following was revealed. (1) The permeability of the egg protoplasm to NaCl and to
saccharose decreases after occurrence of the fertilization. (2) plasmolysis is liable to
occur at the pointed end, i.e. the rhizoid pole, after the egg was transformed to an
ovate form by the morphogenetic movement. (3) After occurrence of the first nuclear
division, the plasmolysis occurs along the equatorial zone as well as at the rhizoid
pole, though the form of the egg is identical with the former stage. This indicates
that a certain change in the physical properties of the cytoplasm is taking place locally
in that zone. (4) At an early stage after the first segmentation, the wall of segmentation
is not firmly connected with the wall of the mother cell, so that it can be
separated from the latter with contraction of the protoplasm upon plasmolysis.View full abstractDownload PDF (598K) -
Toshiro SAEKI1960 Volume 73 Issue 860 Pages 55-63
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESS1. In order to find a practical means of estimation of the production of matter in a plant community and to give a logical explanation to the variability of directly measured values, theoretical analyses have been advanced of the interrelationshipsbetween leaf amount, light distribution and total foliage photosynthesis
2. Inside foliage relative light intensity received by the leaves is not always the same as the light intensity measured at horizontal plane at the same height (Fig. 1). In homogeneous stands the former can be derived from Equation (3), when leaf transmissibility is known and extinction coefficient (K in Equation (2)) is obtained beforehand by 'stratifying clip method'.
3. If photosynthetic capacity in the active leaf and mean respiration rate of all the leaves in a stand are known, the mean total daily photosynthesis of whole foliage is estimated by Equation (5). An example in representative herbaceous species is presented in Fig. 5, where it is clearly indicated that with lower 'leaf area index' daily production in foliage is indifferent to inclination of leaves, while with increase of leaf amount the role of inclination in the production becomes very remarkable, upright leaves being more efficient than horizontal ones under full daylight as demonstrated by Watson and Witts.
4. Compensation light intensity and 'optimum leaf-area index' (Fopt-leaf amount February 1960 SAEKI, T. 63 in the form of LAI for the highest production) are calculated from the photosynthetic capacity in the active leaf and respiration rate of the lower leaf (Equations (6) and (7)). The obtained values seem to be quite reasonable in consideration of the minimum light intensities and 'leaf area indexes' in the natural communities.
5. The highest daily production in a plant community, Pmax, calculated with Equation (8) was discussed in relation to the extinction coefficient and incoming radiation (Figs. 7 and 8). An approximate coincidence was recognized between the calculated values and the highest net production in crop fields collated by Blackman and Black.
The author should like to express his sincere thanks to Prof. M. Monsi for hisView full abstractDownload PDF (1193K) -
Tohru HASHIMOTO, Toshio YAMAKI1960 Volume 73 Issue 860 Pages 64-68
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSComparative effectiveness of gibberellins A1, A2, A3 and A4 (GA1, GA2, GA3
and GA4) in promoting the elongation of rice seedlings, in accelerating the expansion
of green radish leaf disks and of etiolated bean leaf disks, and in inducing the dark
germination of tobacco seeds, was investigated. These four gibberellins were all
active in every investigated phenomenon, but different in comparative activity. In
the leaf expansion and the tobacco seed germination, unlike in the elongation of rice
seedlings, GA4 was especially active and new orders of effectiveness such as GA4_??_
GA3>GA1>GA2 or GA4_??_GA1>GA3>GA2 were observed. It appears that gibberellins
show different effectiveness with different physiological phenomenaView full abstractDownload PDF (553K) -
Yasuo HOTTA1960 Volume 73 Issue 860 Pages 69-74
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESS1. Effect of nitrogenous compounds on the morphological differentiation of gametophyte of a fern, Dryopteris erythrosora, was investigated. Studies were carried out for the most part about the effects of nitrogenous compounds on “the two-dimensional differentiation” (conversion of the filamentous organization to the plate-like one).
(i) In the nitrogen deficient culture the two-dimensional differentiation does not occur.
(ii) NH4-salts are more effective than NO3-salts for the induction of the two-dimensional differentiation. NaNO3 reveals many deleterious effects.
(iii) Several amino acids, which were used in this experiment, are classified in the following three groups according to their effects on the two-dimensional differentiation: a) those which induce the differentiation earlier than in the standard culture, b) later than in the standard, and c) the same as in the standard.
2. Analyses of amino acids both in the alcohol soluble fraction and in residual fraction were carried out at various stages of the gametophyte differentiation. Ten amino acids and two amides were detected in the alcohol soluble fraction; some of them showed characteristic changes in their amounts corresponded to the development of the morphological differentiation. Twenty amino acids including 4 substances of unidentified nature were detected in the residual fraction; significance of the change in their amount is discussed in connection with the two-dimensional differentiation.
3. The author's view (1958) that the qualitative change of protein may be responsible for the induction of the two-dimensional differentiation, is also supported by the results of the present experiments.View full abstractDownload PDF (717K) -
Takeo NISHIBAYASHI, Shumpei INOH1960 Volume 73 Issue 860 Pages 75-80
Published: 1960
Released on J-STAGE: December 05, 2006
JOURNAL FREE ACCESSThe development of sorus of Undaria undarioides (Yendo) Okamura, Eckloniopsis radicosa
(Kjellman) Okamura and Ecklonia cava Kjellman has been observed. In all of three
species both the zoosporangia and paraphyses originate from the meristoderm of the blade.
In Undaria undarioides and Ecklonia cava, the mode of the development of sorus is Laminaria-
type. In Eckloniopsis radicosa, the cuticle of the superficial cells is stripped on the
way of sorus development. This fact seems to suggest that Eckloniopsis radicosa is identical
in the mode of sorus development with Chorda filumView full abstractDownload PDF (759K)
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