1. In the previous report, the effect of the varied day length and night temperature of two or four days duration upon the sex pattern of the cucumber plant was studied. It is observed that long day and high night temperature of even such short duration influenced the physiological state around the floral primordia just going to differen-tiate sexually. Although recovering gradually by the oppositional effect of the prevailing day length and night temperature., these temporarily affected condition seemed to stand rather long even under the day length and night temperature kept to favor the pistillate flower formation. 2. In this report, α-naphthaleneacetic acid (10ppm solution) was sprayed for the purpose of indu-cing the pistillate flower against the long day and high night temperature treatment which favored to induce the masculating condition. In the fore-going report, it is shown by the authors that α-naphthalenacetic acid spray of 10ppm solution induces the pistillate flower formation. 3. α-naphthaleneacetic acid applied at the second period of the seedling development induced the first pistillate flower on the fourth node of the main stem against the prevailing long day and high night temperature. Later application. of α-naphthaleneacetic acid spray induces later-differentiation of the first pistillate flower on the main stem. 4. Following α-naphthale neacetic acid applicat-ion, even on the staminate nodes just beneath the induced pstillate flower node, on which already one-or more ordinary staminate flowers had opened, there bloomed the induced pistillate flowers. The-sex of the floral primordia of the staminate nodes. are reversed by α-naphthaleneacetic acid spray. 5. It is observed that by means of α-naphtha-leneacetic acid spray the pistillate flower differen-tiation is induced even against the adverse day length and night temperature. The effect of α-naphthaleneacetic acid appears so soon but it en-dures not so long against the adverse conditions.
In order to study the fruiting habit of “Issun” broad bean (a large seeded variety), the seeds were sown on the following dates: September 25, October 5, 15, 25 and November 4, in Awa Branch, Chiba Agricultural Experiment Station. The plants planted earlier in the fall made pretty good growth byfore the hard winter season, and even in winter the bean plants continued their development. In the latter part of March, they started to make rapid growth, then stopped their growth at about the end of April, when maximum temperature exceeded 20°C, in all plots irrespec-tive to the dates of their planting. Consequently, the amount of growth was larger in the plants planted earlier than planted later in the fall. The branching of stems was made according to a definite order. The number of stems per plant increased rapidly in the early part of May, and thereafter decreased by the death of the stems. Only 58_??_67 percent of the floower-buds bloomed, and the remainder of the buds aborted before blooming. The earlier the date of the first blooming, the earlier the date of planting was. The number of flowers increased as the temperature went up in the spring, reached its peak, then dropped down uddenly at the middle of April, when maximum temperature exceeded 20°C. Three or four flowering cycles were observed in the planted earlier, while less cycles were observed in ones planted later. 5_??_9 percent of the flowers developed into pods. As the plants planted earlier bore larger number of flowers, they produced more harvested pods. The greater part of pods developed from the first or second flowers in the cluster, and the rates of harvested pods to the flowers in the third: or higher flowers in the cluster were only 1_??_6 percent. The fruiting cycles could not be found in rela-tion to the flowering time, but was found in indi-vidual stems, in which they occured in every four or five nodes, though there were some differences according to the dates of plantings of the plants. Large pods were obtained from the flowers, which had opened between the latter part of Feb-ruary and the early part of March. The size of pods became smaller as the time of blooming was earlier or later than the above mentioned period. The time required from flowering to harvesting was 43_??_78 days, 53 days in average, and the earlier the date of blooming, the more the time required. About 790°C degreedays of heat summation were required from blooming to harvesting of pods.
The composts for raising vegetable seedlings in hot beds are generally prepared by mixing soil, manure, and fertilizers in proper proportion, and leaving them to mature in pile for more than a half year before using. Since we had no standard formu-lar for preparing the composts in relation to the proportion of soil, manure or the amounts of ferti-lizers to be added, the authors intended to know the physical and chemical properties of the exce-llent composts. Twentyfive samples were collected from the gardens raising good vegetable seedlings, and were analysed. The results of analysis showed the following facts. 1. One of the most important factors in rela-tion to the texture and other properties of the com-posts was the organic matter content (loss of ign-ition). The higher the organic matter content, the lower the specific gravity and the apparent specific gravity, and the higher the porosity, mois-ture equivalent, total nitrogen, and exchangeable, capacity (Figures 1-6). 2. The composts for raising cucumber seedlings contained higher levels of organic matter (more than 20 percent in loss of ignition), while the ones for tomatoes contained rather less (12.1_??_18.7 percent). The organic matter contents in the composts for egg-plants were variable, ranging from very low to high (6.5_??_22.8 percent). 3. Hydrogen-ion concentrations of the composts were in the range of pH 5.2_??_8.O, but most of them were in pH 7±1, or nearly neutral in their reaction. 4. Available phosphorous contents were deter-mined by the TRUOG's method and the BRAY's me-thod. The amounts of the available phosphorous found in the samples were in the range of 41 to 1, 110 ppm by the TROUG's method, and 198 to 917 ppm by the BRAY's method. 5. All of the samples except one contained mo-re than 1.0m.e. of exchangeable potassium, and three of them contained more than 10m.e. of it. 6. It was not clear how high of P or K levels were sufficient for the excellent growth of vege-table seedlings, but the amounts in some of the samples, at least, were so high, that they seemed to contain surplus amounts of fertilizers. 7. It was found that fairly large amounts of nitrate and ammonium nitrogen had accumulated in most of the composts tested.
1. In order to establish the seed vernalization technique for the seed production in slow bolting spinach, the author studied the effects of the tem-perature of chilling treatment and of drying of chilled seeds on the floral initiation of spinach. Spinach seeds (var. King of Denmark) were soaked in 1/5M KH2PO4 solution and exposed to tempera-tures of 2°, 5°, or 8°C. for one, two, three or four weeks. On the other hand, some chilled seeds for 2 weeks at 2° and 5°C. were transfered into desic-cator, in which they were maintained for 7, 10, and 14 days. Those seeds were sown in soil in greenhouse flats in spring (March 5) and fall (Oct. 5). 2. The promotive effects of the floral initiation were evidenced by all chilling temperatures, and the longer the treatment period, the greater the acceleration of flowering. 3. In the first experiment (sown in March 5), the plants grown from vernalized seeds passed normally over the courses of bolting, flowering and fruiting, and obtained seeds amounting mostly to 20.3cc in average per plant ip the plots of exposure for 14 days at 2° and 5°C, their size and uniformity were both in good condition, but the obtained quantity decreased in the cases both of longer period and shorter one of treatment than the above mentioned. 4. In the second experiments (sown in Oct. 5), the time of the initiation of floral primordia in vernalized plants was markedly accelerated, but the development of flower stalks was retarded under the short-days in fall; but with the coming of long-day of spring, the plants grown from vernalized and unvernalized seeds were acceler-ated to elongate their seedstalks, those plants, however, showed abnormal flowering and produced small amount of seeds. 5. The promotive effects of low temperature treatments was not nullified by drying chilled seeds for 1_??_2 weeks, but germination of those seeds was checked remarkably.
This experiment was conducted for the purpose of studying the effects of gibberellin on growth and flowering of several ornamental plants. Gib-berellin was applied to the plants with spraying as aqueous solution and single or repeated applica-tions were made. Concentrations of sprayed solution were 20, 40 and 50ppm. Comparison was made between treat-ed plants and non-treated control plants. In many cases, potted plants were treated in glasshouse. 1. Flowering of cyclamen (Cyclamen persicum MILL.) was hastend and this influnce was more remarkable in 40ppm than in 20ppm. Further-more, flower size and length of flower stalk were significantly increased. 2. Flowering of freesia (Freesia refracta KLATT.) was also hastened, but this influence was likely to be limited only to the plants possessing flower buds of fairly advanced stage. No damage or injury caused by the application of gibberellin was found among pollen grains of treated flowers. 3. Plant height and shoot length of petunia (Petunia hybrida VILM.) were both remarkably in-creased. 4. The effect of flower hastening upon winter daphne (Daphne odora THUNB.) became manifest within a week after single application of gibbere-llin. 5. Flower size and length of flower stem of sweet pea (Lathyrus odoratus L.) were increased, but the effect of flower hastening was indistinct. 6. Concerning the experiments with Japanese cherry (Prunus yedoensis MATSUM.) and thunberg spires (Spiraea Thunbergii SIEB.) from which flower budded twigs were pruned and dipped into glass bottles containing water or gibberellin solution, bud sprouting was remarkably hastened and length of flower stem was strikingly increased, but flowering was never hastened by the appli-cation (spraying only or both spraying and dipping) of gibberellin. 7. There were hardly any effects on flowering of potted Kurume azalea (Rhododendron obtusum PLANCH.) in glasshouse, or of Japanese apricot (Prunus Mume SIEB. et ZUCC.), peach (Prunus Persica SIEB. et ZUCC.) and Japanese cherry (Prunus yedoensis MATSUM.) which were planted in the field.
The high temperature treatment of tulip bulbs is known to be an effective method for making the bulbs blind and inducing rapid multiplication of new bulbs. This study was carried out to ascertain the most effective date and length of the treatment on the two varieties, Farncombe Sanders and Prince of Wales. In 1952, the 35°C treatments were started from Aug. 8, Sept. 8, or Oct. 8, for 13, 15 and 17 days. It was found that 20 days treatment started from Aug. 8 had almost no effect, but the treat-ment started from Sept. 8 induced about 50 percent blind, and the treatment started from Oct. 8 did 100 percent blind. In the 1953 experiment, 20 days treatment start-ed from Sept. 15, 13_??_15 days treatments started from Sept. 30, and 10 days treatment started from Oct. 15, respectively, had almost same effect on the bulbs and induced 100 percent blind. The observation revealed that the apical bud in the bulbs were injured by the high temperature treatment, and the axillary buds were promoted to growth, thus the number and the weight of new bulbs were increased. But when too long treat-ments were applied, new growth was impaired, and the yields of the new bulbs were decreased. It seemed that the growth of the axillary buds was promoted by the loss of the apical dominancy in the bulbs with the high temperature treat-ments. The effectiveness of the treatments was varied depending on the date the bulbs were treated or on the varieties used. This may due to the degree of growth or dormancy of the bulbs when they were treated. From the experiments, it was cle-ared that the most successful treatment was about 13 days treatment of 35°C degree started from early October, and when the treatment was start-ed earlier, the bulds should be treated a little longer.
(1) Cuttings of wild rose (Rosa multiflora) were done on various media, i.e. sand, vermiculite, heavy clay soil, and artificially conditioned mold. This mold contained 3.5% organic matter and, 37.7% clay. The rootings and the further growth after transplanting were compared among among these plots. (2) The cuttings on sand, vermiculite and heavy soil rooted slowly and produced thick, un-branched and brittle roots. On the conditioned mold, treated with the soil conditioner (0.05% VAMA or 0.1% HPAN ), the cuttings rooted rapidly and produced fine and branched roots. Moreover, after transplanting to the field the new plants from the sand or vermiculite plots were seemed to be stop-ped their growth, while those from the condition-ed mold continued their growth successively. (3) The advantage of rooting on the conditioned mold was mainly due to the good water-holding and also to the good availability of nutrients of this medium. While the undesirable rooting was probably due to poor available moisture in sand, but to less air-capacity in vermiculite and heavy soil. In vermiculite and heavy soil medium, the cuttings had greater percentage of rooting and more branched roots when they were received a light irrigation. (4) The water-stable aggregates gained by the treatment with the soil conditioner were sifted into seven fractions, i.e. 6-8mm, 4-6mm 2-4mm, 1-2mm, 0.5-1mm, 0. 22-0.5mm, and smaller than 0.22mm in diameter. Then each fraction was used as a rooting medium to determine the rooting res-ponses of the cuttings to the moisture and aera-tion in each plot. For, in this case, factors such as acidity, presence of nutrients, and size and shape of the particles of the media were seemed to be eliminated. (5) In the case of the heavy irrigation, the plot of the 0.22-1mm aggregates were most suitable for rooting, namely the highest percentage of rooting, and. the best root-system were obtained; whereas the plot of the larger or smaller aggre-gates were not better media. In the case of the light irrigation, on the plot of the 1-2mm aggre-gates a lower percentage of rooting was shown. But the cuttings on the plot of the smaller aggre-gates than 0.22mm had a higher percentage of rooting than those irrigated heavily. In the plot of the 0.22-0.5mm aggregates, rooting was scarcely-influenced by the light or heavy irrigation. The finner the aggregate, the less air-capacity was given. The medium which have about 10% or more air-capacity was seemed to be suitable for rooting of the cuttings. (6) Conditioned mold was compared with un-treated mold as a rooting medium. The treatment with the conditioner increased markedly the air-capacity, and subsequently increased the rooting of the cuttings and also the development of their root system.
1. Old peach soil was diluted by virgin soil from 100.5 to 105 times (for example, the soil dilut-ed to 10 times consists of 1 part of peach soil and 9 parts of virgin soil) and peach seedlings were planted in 6-inch pots containing those soils. As the result, the growth in original peach soil was inferior to the control (virgin soil), and the more diluted the soil, the more excellent the growth, and the maximum growth was in 103 times plot. But in the case the soil was more diluted than in this plot, the growth was gradually reduced, and approached to the growth level in virgin soil. 2. On pouring the peach leaf extracts diluted by water from 3 to 1000 times respectively (ori-ginal extract was prepared by immersing the fresh leaves in 10 times water for 24 hours), the peach seedling showed the minimum growth in original extract plot and the maximum in 100 times plot. 3. In sand culture, the ether extract of peach leaves (original extract was prepared by extracting 50g of fresh leaves with ether, and evaporating ether, then dissolving the residue with 50ml of nutrient solution) and its solutions diluted from 10 to 105 times by nutrient solution, were poured on peach seedlings respectively. As a result, the peach growth responses showed the same tendency as in the two tests stated above. The growth in 10 times plot was far inferior to the control (ether extract not supplied) and the growth in 104 and 105 times plot was superior. 4. Generally in these experiments, when peach seedlings were grown in old peach soil or in soil supplied with peach leaf extracts, the seedling growth showed depression, and on the contrary, showed promotion in more diluted plots. It seems that one of its causes is in the presence of some substances which are not nutrient.
1. In order to estimate the amounts of the nutrient elements absorbed by 2 years old (Koyo-hakuto) and 7 years old (Mishima-hakuto) peach trees, all parts of these trees were separated, and trunk, branches and roots were divided into new and old tissues of bark and wood, and weighed, analysed. In addition, the roots system of these trees were researched by the circle form method. 2. Average dry weight of new tissues in these trees were as follows. _??_ 3. The amount of these new tissues was about 89% of the total weight of 2 years old tree, and about 59.2% in 7 years old tree. While, the sum of leaves, one year old branches, flowers and fibrous roots was about 64.5% of the total new tissues, and about 44% in 7 years old tree. 4. Analytical data showed that one year old branches had the highest contents of N, P2O5 and K2O in top parts of the tree, and these contents have a tendency to gradually decrease from 2 years old branches. There was every indication that new bark content was higher than old bark and new wood was higher than old wood in each partitions. Root parts was the same trend to top parts on each partitions, but in each parts the tendency was obscured. 5. Average total amounts of nutrient elements contained in new tissues were as follows. (per tree) _??_ *2 years old tree were planted at a rate of 75 trees per 0.1 hect and 7 years old tree were planted 48 trees per 0.1 hect. and yield of fruits was 1761kg (458kan) The amounts of absorbed nutrient elements, when yield of fruits was 100kan (375kg) per 0.1 hect. (1 tan) 7. Range of roots in 2 years old trees were not observed more than radius of 1m. and at a depth of 90cm, and sum of roots in a partition of radius of 1m and at a depth of 30cm was about 85% of the total roots weight. In the case of 7 years old trees, range of roots were not observed over a depth of 90cm, but the horizontal spread were found to radius of 3 or 4m, and sum of roots in a partition of radius of 1 m and at a depth of 30cm was about 67.8% of the total roots weight.