4th Node Research Articles

Sampling for mineral content in leaves of mango cultivar ‘Dashehari’

A rapid and continuous increase in the dry-matter and ash content in mango leaves was observed from the base to the top of the shoot up to 4 months after the leaf emergence. The levels of N, Ca and Mg in leaves increased, whereas P and K content decreased with the advancement in the age of the leaf from the base to the top of the shoot. The stabilization of all constituents was observed in leaves 4–5 months old borne on 4th and 5th nodes from the base of the shoot. Thus, while considering the nutrient status of a tree as a whole, leaves of the said age and position should be sampled. For the individual elements leaves of varying ages should be sampled, viz. 2 months old leaves may be sampled for P and Mg, while for K leaves should not be less than 3 months old. As regards Ca and N, leaves should be sampled after 4 months.

Studies on Competition and Compensation of Crop Plants : IV. Effects of the methods of cultivation on the contribution of tiller of rice plants in relation to the position

Rice plants var. Nihonbare were grown at three culture methods. Mature seedlings and young seedling and of rice plants were transplanted at a single plant per hill or the seeds were directly seeded on upland field. The number of tillers on each position of tillers and leaf area of them at several growing times were determined. The results were obtained as follows. 1. The tillers were observed to appear at nodes above the 7th node, the 3rd node, and the 4th node, in mature seedling plot (M-plot), young seedling plot (Y-plot), and direct seeding plot (D-plot), correspondingly. 2. The number of tillers in two lowest tillering nodes were markedly larger than that in higher position of nodes. The contribution of the former to total number of tillers was 64.7% (M-plot), 54.1% (Y-plot), and 60.6% (D-plot) at maximum tiller number stage, and 66.8% (M-plot), 60.4% (Y-plot), and 64.5% (D-plot) at harvesting time. 3. The sum of leaf area of the tillers in the two lowest nodes at the time of maximum leaf area was markedly large as in the case of tillers, and its contribution to total leaf area per hill was 63.8% (M-plot), 55.9% (Y-plot), and 59.4% (D-plot)

Effect of Carbon Dioxide Concentration on Growth and Dry Matter Production of Crop Plants : 1. Effects on leaf area, dry matter, tillering, dry matter distribution ratio, and transpiration

Crop plants at the 5 to 7-leaf stages possessing C3 (barley, rice, and soybean) and C4 (barnyard millet and maize) pathways of photosynthesis were cultured for 15 days in transparent growth chambers placed outdoors under 4 different carbon dioxide (CO2) concentrations from 1/2 to 10 times the normal atmosphere (ca. 350 ppm) to make clear the effects of various CO2 concentrations on growth and dry matter production. The following results were obtained: I. Increases in plant height and leaf area were promoted by high CO2 concentrations, but the degree of promotion was relatively small. At a low concentration (160 ppm), plants often elongated and had narrow drooping leaves as compared to control plants under normal CO3 concentration. 2. Increase in dry weight was promoted by high CO2 concentrations and suppressed by a low concentration. This increase proceeded up to about 3 times (sometimes 10 times) the normal concentration, and this was effected mainly through the increase in net assimilation rate. The C3- and C4-plants responded differently to CO2 concentrations, the latter giving less suppression at a low concentration and less promotion at high concentrations than the former. 3. Tillering in barley and rice was accelerated by high CO2 concentratoins and withheld by a low concentration. In rice plants, observed at the 7-leaf stage, the promotion of tillering took place at the 4th node, and the appearance of tillers was made steadier at the 2nd and 3rd nodes by high CO2 concentrations. 4. Distribution ratio of dry matter in rice and maize was in a marked contrast. In rice plant distribution to leaves was less and that to roots was increased at high CO2 concentrations, while in maize such a tendency was not observed at all. 5. Transpiration rates (dm-2 day-1) were smaller at higher CO2 concentrations. At a low concentration, the promotion of transpiration was enhanced day by day as the treatment proceeded. On fine days, the leaf temperature was about 1°C lower at a low CO2 concentration and about 1°C higher at higher concentrations as compared to control plot, but no difference was observed on cloudy days.

Location of Fruit on Grapevines in Relation to Cluster Size and Chemical Composition1

Abstract This paper reports an extensive study on fruiting habit of 15 grape cultivars representing different species and interspecific hybrids. Blossom records of 4 cultivars showed highly significant differences of up to 3.5 days between full bloom dates of the 1st and 4th flower clusters on a node. Significantly more crop was produced on the 9th node than on the 1st node and also on the 5th node than on the 1st node for 13 out of 14 cultivars. Only slight and generally nonsignificant differences in acid and solids content were found between fruit on the 1st, 5th and 9th nodes. With most cultivars there were significantly fewer fruit clusters on the 1st and 2nd than on the 4th to 8th nodes on a 10-node cane; numbers of fruit clusters tended to be constant from the 4th to the 9th node on a cane. Characteristic numbers of flower clusters per node are reported for different cultivars. With 8 out of 14 cultivars, wt of fruit on an individual node decreased significantly from proximal to distal cluster, in some cases the 1st cluster was more than twice the wt of the 4th. Significant decreases in solids and increases in acid content were found between proximal and distal clusters only in 4 cultivars.

Studies on Set Germination and Early Growth of Sugarcane : I. Relation between the development of above-ground parts and shoot roots of growing young cane

Experiments were undertaken to clarify the relation between the development of above-ground parts and shoot roots of growing young cane. Five varieties of cane cuttings were planted under various conditions (soil, vermiculite, age of cuttings, date of planting and fertitiy of soil). After germination, the emergence of leaves and shoot roots were observed. The results obtained were summarized as follows: 1. The first shoot roots did not emerge until the 13th leaf (8 leaf scales plus 5 complete leaves) emerged, and the first shoot roots originated from the 6th basal node of young shoot. This relation was recognized at all the conditions examined. Basing on the above finding, the rooting of the shoot roots may be predicted by counting the leaves of above-ground parts. 2. The shoot roots of a given node emerged and elongated simultaneously with the leaf of a node which is higher than the former by seven. In other words, when a leaf was emerging, the 7th node counted downward from the one to which the leaf was attaching, posessd the ability of rooting, and this relation was maintained throughout the whole growing stages of cane. This fact may give a scientific foundation to the usual practices for preparing cuttings from a sugar cane shoot.

Some factors affecting the Hill reaction activity in cotton chloroplasts.

A method of plant culture was developed for growing large leaves of glandless cotton on single stems. Chloroplasts isolated from these leaves actively reduced ferricyanide when assayed for the Hill reaction. Hill reaction activity increased 133% when the 0.5 m sucrose isolation medium was replaced with 10% (w/v) polyethylene glycol, both buffered at pH 7.6. The presence of 2 or 5% (w/v) bovine serum albumin in the sucrose buffer did not increase Hill activity. Ferricyanide reduction in the dark occurred in all assays, and the possibility of gossypol as the reductant is discussed. Half-life of the chloroplasts stored in 10% glycerol at -23 C was 23 days. The ammonium ion at 0.01 m enhanced Hill reaction activity up to 171%. Leaves containing chloroplasts with the highest Hill reaction activity were found near the 8th node below the apex. Leaf water potentials less than -28 bars reduced the activity about 50%. Daylight conditions during the winter months in the greenhouse reduced the activity about 30%.

Studies on the Wilting Treatment of Corn Plants : III. The influence of the artificial auxin control in nodes on the behavior of rooting

The authors reported in previous paper that on the corn plants wilted temporarily at young stage about 6 leaves age or successively at the early stage of stem elongation about 9∼12 leaves age, the growth and fodder yield showed the tendency to increase by growing under the adequate soil moisture condition after rewatering, and that even at the stage of rapid stem elongation about 15∼18 leaves age they did so in case of a rapid drought of soil moisture. It was reported in last paper that (1) the number of roots from the nodes on which rooting occurred after rewatering increased, on the corn plants wilted successively for few days or sprayed gibberellin, (2) the rooting from the upper nodes on which it didn't take place under the normal condition was accelerated, (3) there was the regularity in the behavior of rooting on the corn plants, it was related to the closing an internodal elongation. Considering from these phenomena, it may be thought that the rooting and internodal elongation are carried away by auxin level in the neighboring nodes, and that the wiling treatment is concerned with the auxin level in the neighboring nodes. In present experiment, the auxin level in the neighboring nodes was changed artificially by using a few ways i.e. lodging, added NAA or TTP to 6th, 7th and 8th nodes and X-irradiation. Then these treatment shows the same influence as the wilting treatment on the behavior of rooting. 1. On the corn plant lodged, the lower parts of each internode which is elongating are bended and the plants pick themseves up. This phenomenon is due to undergo a change in the auxin level in the neighboring nodes, thereafter to impede the growth of internodal parenchyma in inner side of bending stem and to accelerate it in outer side. Further it is observed that the rooting from the inner side of bend is impede and the rooting from the outer side of it is accelerated and that the rooting from the upper nodes on which it doesn't take place under the normal condition is promoted, too. 2. As NAA or TTP is supplied on 6∼8th nodes, the rooting from those nodes is accelerated, thereto the rooting from the more upper nodes which it doesn't take place under the normal condition is observed, too. 3. For the investigation used drought and X-irradiation at the same time, though the development of brace roots is accelerated by drought, the number of brace roots which develop after X-irradiation decreases even if the previous treatment is drought or not. 4. These auxin variations in the neighboring nodes made the rooting and internodal elongation accelerate. It may be very interesting because it's able to consider that hydrolysis of protein is progressed under the wilted condition and then TTP or IAA increase in the corn plants. As the result of the raising of the auxin level in the neighboring nodes these morphological changes are brought on.

Air and Soil Temperature and Phosphorus Effects on Mineral Uptake and Distribution in the Pea Plant1

Abstract The effects of 4 air and soil temperature regimes and 3 levels of P on the concentrations and total contents of N, P, K, Ca and Mg in pea plant tissues were investigated in controlled environments. There were generally no significant interaction effects between temperature regimes and applied P when contents of these minerals were expressed as per cent of dry matter. When contents were expressed as total uptake into the various tissues there were significant interactions for all 5 minerals. At the pre-fruiting growth stages, tissue concentration of P generally increased with applied P, particularly at the highest rate. P concentration responses at the 10th node stage were similar to those at the 6th node, but there was a reversal of these effects at full bloom. The warm air temperature of 30°/21°C (day/night) generally increased P concentration but depressed total uptake compared with a temperature of 21°/13°. The increases were largely due to concentration effects resulting from smaller plants. Increases in P concentration at the high soil temperature of 18°, compared with 10°, were absolute because they occurred regardless of plant size. Applied P increased the total uptake of minerals as well as their translocation into the seed.

Air and Soil Temperature Effects on Growth Response of Peas to Phosphorus Fertilization1

Abstract The effects of 4 air and soil temperature regimes on plant growth and pea yield responses to applied P were investigated in controlled environments. The plants were grown in a low-P (4 ppm) Monroe silt loam, and harvested at 4 predefined stages of plant development. At the 6th node stage applied P increased vine (leaf and stem) weight only at the 21°/13°/18°C day/night/soil temperature regime. At the 10th node and full bloom stages P increased vine weight at all temperature regimes. Increases due to P were greater at the high soil temperature of 18° than at 10°. The increase due to P at the high soil temperature was greater at the cool air temperature of 21°/13° than at 30°/21°. At estimated marketable maturity of peas, P increased the dry weights of the root, vine, pod and pea seed at all temperature regimes, but the magnitude of such increases depended on the tissue and the temperature regime. Efficiency of P in promoting pea yield was greater at the high soil temperature, particularly at cool air temperature. The nearest optimum temperatures were a day/night air temperature of 21°/13° and a soil temperature of 18°. The nearest optimum P rate was 50 kg/ha.

Flowering pattern, floral abscission and yield attributes in soybean influenced by GABA

An experiment was carried out in the field laboratory of the Department of Crop Botany, Bangladesh Agricultural University, Mymensingh, to investigate the flowering pattern, floral and pod abscission under untreated and GABA (mixture of GA3 and Abscissic acid) treated soybean and their trends concern to yield. The variety of soybean PB-1 (Shohag) was used in the investigation. GABA at 0.5, 1.0 and 2.0 mg L-1 of water with a control (only water) were used for foliar spray. Flower and pod initiation started from 54 and 60 DAS in all plants irrespective to GABA treatment. Flower production trend showed a deltoid pattern where pod production was gradually increased and slowed down at 74 DAS but not in GABA treated plant. The 4th node produced the highest number of flowers, then decreased and got zigzag pattern in upper nodes. GABA treated plants produced more nodes per plant and followed lower trend in flower and pod abscission indicated the efficacy of higher yield. Keywords: Flowering pattern; Floral abscission; Yield; Soybean; GABA DOI: 10.3329/jbau.v8i1.6394J. Bangladesh Agril. Univ. 8(1): 29-33, 2010

Studies on the First Jointing Stage in Rice Plants : Morphogenetic Phases of Stem Development in Rice Shoots

The present paper is a report on the formation of first internode and beginning of internodal extention in rice shoots, and it also describes the varietal differences and ecological responses to the varying times of cultivation. Definitive nodes and internodes are here defined as those that are clearly delimited in longitudinal median sections of living shoots as observed using dissecting microscope. By these easy methods, the first discernible internordal lacunae are considered here as an index of internodal extension. From the results of this observation on the morphogenetic process, the author proposed that the stem development may be divided into the following three phases; viz. previous phase of internodal lacunae formation named "Primitive phase", process of subtle elongation of basel telescoped lacunae (Crown-internodes) named as "Primary phase", and the following phase showing the rapid and long extension of upper internodes (Culm-internodes) named as "Secondary phase". It is observed that the stage of first internodal formation in the Primary phase may correspond to time far previous to differentiation of panicle primordium. The plant-age as measured by the number of leaves is about 5.5. And in most plants, first extended internode is that between 5th and 6th node, however, the locus of this node keeps lower in short-term varieties and in plants planted late, but upper in long-term varieties and in early planted plants. The number of extended internodes in Primary phase may be found 5 or 6 in most plants, and are less in short term varieties but more in long-term varieties. However, ecological variations due to the varying of planting times are a little. These internodes are 1-2 mm in length at the beginning of formation, and are extended just about 3 mm in full length. And the internodes which are extended over 3 mm in length may be regarded as the internodes of Secondary phase. At the stage of onset in Secondary phase, the panicle is 0.4∼1.0 mm in length, and the stage ranges from the branch differentiation to early time of spikelet formation. And the plantage is 11.0∼14.0 leaves, leaf number index is 83 to 87, and the Secondary extension of internode begins from the node of 10∼13th leaf. Each above-mentioned value is revealing the range of varietal differences. It seems that the "crown" of Grasses may be divided into two types with or without of "crown-internode"-Rice-type crown (with) and Wheat-type crown (without). From the results of this studies, the author stated that the simple method using dissecting microscope may be useful for identifying the internodal formation and extension not only at the Secondary phase but also at the Primary phase, without any trouble as by paraffin method.

Gibberellin Effect on Tryptophan Metabolism, Auxin Destruction, and Abscission in Coleus

AbstractApplication of gibberellic acid (GA) to the apical region of the stem enhances 14CO2 release from tryptophan‐l‐14C in cell free preparations of the apical region. Although GA when applied to the apical region markedly accelerates abscission rates of debladed petioles at the 4th node, the enhancement effect on tryptophan metabolism appears to be restricted to the apical bud region. The increased levels of diffusible auxin in Coleus stems, observed earlier by Muir and Valdovinos (1965), appear to be due to the GA effect on auxin precursor conversion rather than to an altered rate of auxin destruction. GA pre‐treatment does not significantly alter destruction rates of auxin in the stem tissue. This is demonstrated by the release of 14CO2 from IAA‐1‐14C by sections of internode tissue.While a multiple deblading pattern retards abscission of debladed petioles considerably, application of GA to debladed petioles at the basal region of the stem restores the normal rates of abscission at debladed distal nodes. No significant change in the abscission rates at treated nodes is observed. The GA effect on abscission at distal nodes is attributed to the effect of the growth substance on auxin precursor conversion in the apical region. In these experiments, as in the case of plants treated in the apical region with GA, auxin destruction rates in the stem are not altered significantly.

Studies on Starch Contained in the Tissues of Rice Plant : IX. Distribution of starch near the shoot and root apices.

Using several varieties of japonica rice, the auther observed the distribution of polysaccharides or starches near the shoot apex and the root tip under the microscope. The sections cut by paraffin method were stained chiefly by Schiff's reagent. The results are summarized as follows: 1. Normally two parts, 2-layered tunica and corpus can be recognized in the vegetative shoot apex. No polysaccharide granule can be found in the parts where the cells have much proteins and dividing activity; that is tunica, outermost layer of corpus, and leaf primordia just after differentiation. However, in later when the primordia of 1st order panicle branches cease to differntiate and shoot apex does not grow any more with only one tunica layer, small granules of polysaccharide appear even in the tunica and outermost corpus layer. In the vegetative shoot apex, cells in the 4th layer, that is the 2nd layer of corpus, begin to contain minute polysaccharide, and thereafter the cells of corpus located inwards and downwards contain gradually larger granules. It is suggested that sugars translocated from the leaves reach to the shoot apex, being consumed immediately by the active cell division without remaining any stock-polysaccharide, but that in the older cells which are relatively weak in cell division, sugars are stored as polysaccharides for a while. These polysaccharide or starch grains become larger as the cells become older and larger until the cells grow very rapidly into large ones consuming almost all starch contained there. 2. The axis is continuous from the corpus, but the differentiation of nodes and internodes are not clearly observed before the insertion of leaf-3 in which a band of starch begins to be recognized. Transitory starch grains are abanduntly stored in the nodal regions being larger as the nodes become older. At the VII node, the nodal plate grows into stellate parenchyma and the stored starch disappears, thereafter it does not store starch. Starch is also found in the internodes, but its amount is less than that in the nodal plate, especially in the central part which becomes lacuna later on. The cells in the VI-VII internode elongates so rapidly, consuming stored starch probably, that there can not be found any starch in the internode just after the completion of lacuna formation. However, the internodes gradually restore large compound starch grains soon which are dissolved and translocated to the other parts, especially to panicle, during the ripening period. 3. The base of young leaves also contain starch. The older the leaves become, the larger the starch in the size, and the largest starch can be seen in the base of 5th leaf. The starch in the 6th leaf base abruptly disappears, and this is probably due to the consumption caused by the rapid elongation of the cells. In this stage the leaf elongation almost ceases, adcompanying lacuna formation, and then the leaf-sheath restores much starch grains till they are translocated to the other parts, especially to panicle. 4. It is an interesting fact that the 6th leaf sheath, VI-VII internode, and VII node elongate very rapidly almost simultaneously accompanying tiller elongation and rooting from the VII node, and the temporarily stored starch in the above tissues disappears abruptly with their rapid elongation. 5. Root cap always contains much falling starch, but meristems of root tip scarecely have polysaccharide granules except the regions which Dr. Clowes called "Quiescent Center". In general, relatively great size of starch grains exist in the young metaxylem cells, and smaller ones in the cortex parenchyma, but in either case starch disappears with the rapid elongation of these cells, and thereafter they do not restore starch any more. But in the cases when much starches are forced to be stored in the tissues of shoot, restored starch can be seen in the cortex parenchyma in the base of each matured root. 6. [the rest omitted]

Studies on the tillering in genus Allium. VI

In this paper, the mechanism and mode of the tillering of Chinese leek were studied using var. “Oba-Nira” under natural conditions. 1. The mechanism of the tillering of Chinese leek is similar to that of the welsh onion with the exception of the following single point mentioned in 2. 2. The 1st and 2nd leaves of the tiller are usually formed on the phyllotaxy plane of the mother plant, however the 3rd and subsequent leaves are not formed on this plane. Soon after the commencement of tillering bud formation, the phyllotaxy plane of the mother plant changes its direction unmethodically. Namely, while the phyllotaxy planes of tiller and mother plant are on the same plane at first, later they become separated from each other. 3. In a plant which has fully developed in tillerings, the tillers are arranged in a circle or elliptical group. In this case, there is no rule as to the arrangement of these tillers. 4. The indications of flower bud differentiation are quite similar to those of the welsh onion. The initial stages of involucre formation becomes discernible in middle June, and flower cluster development progresses rapidly until the flowers commence to bloom in early or middle August. Soon after the beginning of involucre formation, a new vegetative axillary bud is formed at the base of the primordium of the flower cluster stalk. This bud developes in parallel with the flower cluster and grows into a perfectly developed mature plant. 5. Under natural conditions, the first tiller of seedling appeared at the 6th or 7th node of the main plant, and the percentage of appearance at the 6th node was 71.4 and that at the 7 th node was 28.6. Most of the 2nd and subsequent tillers appeared at the 1st, 2nd or 3rd node after the preceding tiller had occurred, and the frequency of appearance at the 2nd node was the highest. 6. The average number of tillers coming from a seedling in a growing season was 23.6, and that of differentiated leaves was 150.5. 7. At times, the development of a tillering bud was so slow that the tiller appeared from the leaf sheath of preceding node too late to be normal. These abnormal tillerings were frequently observed in the late stage of the growing season. No examples of other types of abnormal tillerings were observed in Chinese leek.

Studies on Blooming and Fruiting in Soybean Plants, especially on the Relationship between Blooming and Fruiting on Each : Node in soybean plants and weather conditions and production practices.

The variety, Norin No. 4, were seeded on 15th May and 30th June in 1958 and 1959 with two stands, light and heavy. The blooming and fruiting in each node were observed. The results obtained are as follows: 1) The weight of leaves and stems and the number of pods were larger on the early seeding plot than the late one, on the plot of light density than the heavy stand and in the test in 1958 than 1959 especially on the early seeding plot. The percentages of fruiting were not constant with plots. 2) There were a fundamental type of blooming and fruiting in each node of both of the main stem and branches of the plant, the largest number of flowers and pods were observed on the top node and the 6th to 8th node from the top, and the fruiting percentage and mean weight of a seed were high on the node of the second to 5th node. 3) However, there were some differences with production practices, the number of flowers and pods in the branches were changeable in each node but on the main stem they were favorably constant especially on the second to 5th node. Higher yields were obtained when the nodes with many flowers and pods were shown on relatively lower position. The more differences were shown between the most efficient node of flowering and podding the lower fruit-setting percentage were observed. 4) Such differences of flowering and fruiting came mainly from the differences of the duration of sunshine, the light intensity on the lower leaves and the growth of leaves and stems. Consequently, the number of flowers depended upon the amounts of the reserves of assimilates untill the period of the differentiation of flower buds and the pods number depended upon the amounts of the assimilates during 30 days after the blooming stage. 5) It was clarified that the important period and leaf position to decide the number of flowers and pods were different and there were some changeable nodes in the number of flowers and pods with production practices. The data shown might be very important to promote the soybean yields.

稲線虫心枯病罹病株の高位節からの異常分枝について

On thc rice plant affected with Aphelenchoides bessevi, are often observed abnormal tillers which shoot out from higher nodes of mother culms, mostly from the 2nd to 4th nodes, being counted from up to down. The abnormal tillers occurred more frequently in the case of rice plant that absorped excess amount of nitrogenous fertilizer, during the development of ears of the mother culms. It was noticed that the abnormal tillers produced unripe ears and the mother culm was restricted its growth, causing reduction of the weight of ear, due to branching tillers.

On the Development of Branch-roots on Successive Nodes of Rice Plants

In the present experiment the author wanted to obtain some further understandings on the relations existing between development of the branch-roots and emergence of the leaves, and on the growth mode of the branch-roots under lowland conditions in comparison with that under upland conditions. 1. The author noticed two kinds of branch-roots (bigger and smaller). Diameter of the smaller one was 0.035∼0.075 mm and that of the bigger 0.25∼0.30 mm. The bigger branch-roots branched further but the smaller didn't. 2. Development of the primary, the secondary, the tertiary and the fourthly branch-roots etc. on successive nodes proceeded at the same pace as the period of leaf emergence in the similar way as has been seen in wheat plants. 3. The roots under upland conditions made many branches waving conspicuously, and the number of big secondary roots (mentioned at 1) was twice to three times that under lowland conditions. And branching was repeated so much as to make even fourth order branch-roots under upland conditions, while it did not go further than to have tertiary branch-roots under lowland conditions. Mat roots developed vigorously at the nodes higher than the 8th node under lowland conditions, but they were not observed under upland conditions. Under lowland conditions the root maintain its activity for a shorter period becoming to decrepitude earlier than upland conditions.

Ecological Studies of Fruiting Behaviours of Azuki Beans : Phaseolus angularis W. F. Wight

Experiments were conducted on fruiting behaviours of Azuki beans, and although final conclusions could not be made with regards to all the varieties, the following points were observed in the variety Wase-maruba which is commonly cultivated in Hokkaido. 1) Blossoming commences usually from the 1st node of the 5th and the 7th branches, and succeeds upwards until the last node is reached, whereas in the 3rd branch blossoming starts from the 2nd or 3rd node and in the 4th branch from the 2nd node. In every inflorescence the blossoming almost invariably commences from the basal flower, whereas the ones which appear in its lower sites are actually the growth of adventitious buds. 2) Blossoming period ranges for over a month, but mainly is for 3-4 weeks. 3) The blossoming curve for the 1st week from the initial blossoming is comparatively low, in the slope and is followed by a rapid rise with a peak continuing for 2 weeks upon which the curve gradually descends. 4) Fluctuations in the number of dropping flowers and pods during flowering are as follows : whereas the number is almost negligible until the 1st half of the blossoming peak, the number gradually increases and after the 2nd half on a sudden rise in numbers is seen. The pod dropping continues even after the termination of blossoming, but the majority drop within 1 week. from the beginning of flowering. 5) In regards to flower and pod dropping with reference to stem-node order, the rate is the lowest in the 6th, 7th and 8th middle nodes and is medium in te 5th, 4th and 3rd basal nodes and also in the 9th, 10th and 11th tip nodes. In the nodes upper than the 12th the rate rises rapidly. Thus it may be said that the pod-setting on main stem is influenced remarkably by the site on it. 6) In the majority of flowers it was observed that the embryo-sac formation as well as the fertilization were, almost completely functioned, and therefore the causality for above-mentioned flower-and pod-dropping should not be failures in those functions.

Studies on the Development of the Ventilating System in Relation to the Tolerance against Excess-Moisture Injury in Various Crops. : VII. Comparative studies on the ventilating pressure in lowland and upland rice plants growing under flooded and under water economized conditions. : VIII. On the ventilating system and the ventilating psessure in various plants growing on lowland and on upland.

Further studies were made on the ventilating system in various plants in relation to the ventilating pressure, the results being summarized as follows: 1) A highly developed ventilating system was observed in various lowland plants, wherever they might be grown, They exhibited a lower ventilating pressure, varying almost in accordance with the metabolic activity of their roots. 2) On the contrary. feebly developed ventilating systems were observed in upland plants, as far as they were growing under dry conditions. They could accomodate themselves to over-moist haditats, by means of reconstructing the ventilating system likely enough to make it possible for their roots to receive considerable amounts of oxygen from their tops. Considerable degrees of reformaticn in the ventilating system and renewal of the root system were observed when they met with over-moist conditions. 3) Referring to the POISEUILLE's and FICK's laws, a theoretical explanation of the relation between the significance of the ventilating pressure and the gaseous diffusion from the top to the root was presented. Explanation of figures The dotted portions in all the figures refer to the intercellular spaces containing much air or the tissue having those spaces. The abbreviations are as follows : Ca, cavity; co, cortex or hypodermis; en, endodermis; ep, epidermis; ha, hair; ly, lysigenic space; pi, pith; rh, root hair; rv, reinforced vascular bundle; sv, separated vascular bundle; sz, sizogenic space; va, vascular bundle. Rice plant (common to the lowland and upland rice pldnts). Fig. 1. Internode of the peduncle. Fig. 2. The 1st internode (the uppermost). Fig. 3. The 2nd internode. Fig. 4. The 3rd internode. Fig. 5. The 4th internode (the lowest elongated one). Fig. 6. Not elongated internode in the 5th order. Such an internode is a component of the so-called tillering portion, totaling about 12 internodes in succession. Barn-yard grass and other grasses. Fig. 7. Internode of the peduncle. Fig. 8. The 2nd internode. Fig. 9. The 4th internode. Fig. 10. The 6th internode (the lowest elongated one). Fig. 11. The stem of Ranunculus sceleratus. Fig. 12. The stem of Veronica Anagallis. Corn plant growing on upland (12 leaf-stage). Fig. 13. Middle portion of the 4th green leaf-sheath. Fig. 14. The 4th node to which the 4th green leaf-sheath is attached. Fig. 15. The 6th internode. Fig. 16. Root zone with a crown root. Fig. 17. Basal portion of a crown root. Fig. 18. Middle portion of the crown root. Corn plant kept flooded (12 leaf-stage). Fig. 19. Middle portion of the 4th green leaf-sheath. Fig. 20. The 4th node to which the 4th green leaf-sheath is attached. Fig. 21. The 6th internode. Fig. 22. Root zone with a crown root. Fig. 23. Basal portion of a crown root. Fig. 24. Middle portion of the crown root.

Studies on tillering in paddy rice. : 1. Increae system of tillers.

The authors made an experimental study on tillering in paddy rice under the cultural conditions of direct sowing and transplanting. With variety Rikuu 132, cultures by both of these methods were practiced in 1947. Sowings were done on May 5. Transplantings were made on June 9 in one plot and on June 19 in another. Each plant was given a space of 1.2×0.4 shaku either in direct-sown or in transplanted plot. The numbers used for investigations per Plot were 40. In the direct-sown culture the first tiller appeared quite usually from the 2nd node (the 1st normal-leaf node) on main stem, while in the transplanted one some lower nodes remained dormant in most cases and the frst tiller appeared usually from the 4th or 5th node. Moreover, in the former, tillers appeared quite regularly in order from the lowest one to the succeeding upper ones, while in the latter, such regularity was not the case with some lower ones. In the former, however, the last tiller on main stem was that from the 9th node, while in the latter the 10th node shooted it. Lateral tillers in the transplanted culture were apparently less in number than in the direct-sown culture. Tillers appearing from a main stem are named 1st-order tillers, those from a 1st-order tiller are named 2nd-order tillers, and so on. A node on main stem and certain nodes on tillers bear mutually a corresponding relation regarding their loci. When the 1st tiller appears, from the 2nd node on main stem (node 2), the node 2 has no corresponding node. Corresponding relations of upper nodes on main stem with nodes on 1st-order tillers are: Node 3 (3rd node on main stem) with 1 node, 2p (the 1st or prophyl node on the tiller from node 2); node 4 with 2 nodes, 22 and 3p; node 5 with 3 nodes, 23, 32 and 4p; node 6 with 4 nodes, 24, 33, 42 and 5p; node 7 with 5 nodes, 25, 34, 43, 52 and 6p; and so on. WhenY=number of corresponding nodes on tillers, n=the node number of a given node on main stem, n'=number of nodes from 1st node to n-node, and loman figure I shows 1st-order tillers, then YnI is n'-2 in this case. In a case where the 1st tiller is from the 3rd node on main stem, YnI is n'-3; and in a case where the 1st tiller is from the 4th node, YnI is n'-4; and so on. So, the number of corresponding nodes on tillers is presented by a formula YnI=m, where m=n'-number of nodes from 1st node to 1st-tiller node on main stem. Corresponding relations of nodes on main stem with those on 2nd-order tillers are: When the 1st tiller appears from node 2, neither node 2 nor node 3 has corresponding node. Node 4 corresponds with 1 node, 2pp; node 5 with 3 nodes, 2p2 22p and 3pp; and node 6 with 6 nodes, 2p3, 222, 23p, 3p2, 32p and 4pp. Thus, node 7 corresponds with 10 nodes, node 8 with 15 nodes, node 9 with 21 nodes, and so on. The general formula is YnII=m(m-1)/2. Smilarly, the number of corresponding nodes on 3rd-order tillers is presented by a formula YnIII=m(m-1)(m-2)/6. Consequently, the total number of nodes on tillers of all orders corresponding with a given node on main stem is: Yn=YnI+YnII+YnIII+······or Yn=m+m(m-1)/2+m(m-1)(m-2)/6+······. Among the nodes belonging to the same group regarding corresponding relation, there is a difference in their physiological activities giving a phenomenon that new tillers from the nodes on later-order tillers as well as from those on upper tillers of the same order are apt to appear later and to be weaker. However, in spite of the fact that the prophyl node is the 1st node on a tiller, it bears in a few cases merely a comparatively weaker tiller. In the present experiment, tillers from prophyl nodes appeared rarely in the transplanted culture but none was in the direct-sown culture. The phenomenon of tillering caused by the difference of physiological activities among nodes is quite regular in the young stage of plant. [the rest omitted]