In the previous reports(6, 7, 13, 14), it is emphasized that the presence of fruits seems to be the dominant factor in the flowering behavior of Unshu orange trees. The presence of fruits restricts the flower formation. It follows that the flowering shoots in the following year decrease and at the number of flowers per flowering shoot tends to decrease.
In this paper, results of the experiments with Unshu orange trees on the effects of time and severity of fruit thinning and time of harvest upon the flower formation for the following season are reported.
In 1955, thinning was performed on July 12, August 11, 30 and September 16. Blossom bud per cent of total sprouted buds on the defruited shoots decreased in the following order: 42.8, 20.8, 12.5 and 4.0 (Table 2), as the fruit was thinned later in the season.
In 1956, thinning was performed on June 10, July 9, 28, August 17 and September 29. As the fruit was thinned later, blossom buds per cent of total buds on the defruited shoots decreased in the following order: 20.9, 18.9, 1.3, 1.1 and 1.6 (Table 3). The per cent of blossom buds formed on the bearing shoots, un-defruited, in the domain of the influence of the fruit thinning as above related, decreased in the following order: 1.4, 0.8, 0, 0 and 0 (Table 3). The effect of fruit thinning was reflected even to the behavior of the un-defruited bearing shoots.
In 1957, the effects of time and severity of thinning and time of harvest were examined. The results are shown in Fig. 2.
Early or heavy thinning and early harvest favored the flower formation for the following season.
It is concluded that the annual bearing can be maintained if attention is paid to balance the proper leaf with fruit year to year. As for the time of the fruit harvest, the earlier the mature fruit can be picked the greater will be the nutrient supply for the next crop.

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1. The effects of physical and chemical properties of soils weathered from different parent materials on the growth of Satsuma oranges were investigated from 1957 to 1962. The concrete frame used for the experiment had area of 3.24 square meters and depth of 1.2 meters. Soils examined were collected from main citrus raising areas in Ehime Prefecture, and they were derived from different parent materials as follows:
Sekizen soil: Paleozoic graywacke and lime stone
Futami soil: Chlorite schist
Ohira soil: Biotite andesite
Yoshida soil: Mesozoic sand stone
Ono soil: Diluvial
Idai soil: Granodiorite
2. Judging from the volume of tree crown, the enlargement of trunk diameter, growth of shoots, amounts of pruning and fruit yield, the growth of Satsuma oranges was superior in Sekizen and Futami soil, inferior in Ono and Idai soil, and intermediate in Ohira and Yoshida soil. The shoot growth in Ono, Idai, Ohira and Yoshida soil was greater in organic fertilizer (fish manure etc.) than in the inorganic (ammonium sulphate etc.).
3. Among 6 different soils examined, there were conspicuous differences in the gravel content, soil texture and other physical properties. Soil organic matter was slightly abundant in Sekizen and Futami soil. Soil reaction was slightly acidic in Sekizen soil with the high degree of cation saturation, but was strongly acidic (pH 5.0-4.5) in other soils. Cation exchange capacity was great in Ohira and Futami soil. In the inorganic fertilizer plots, soil pH of 10-30cm depth lowered remarkably, while that of top soil (0-10cm) became high by the application of dolomite in the fifth year. The lowering of soil pH was slight in organic fertilizer plots.
4. Comparing the changes of nitrate nitrogen of top soil from March to November in Sekizen, Yoshida and Idai soil, Sekizen soil was highest almost throughout the season, followed by Yoshida and Idai soil in order. In the organic fertilizer plot the content of nitrate nitrogen in top soil was higher than in the inorganic fertilizer plot especially after summer. The nitrate nitrogen content might become one of indexes which indicate the difference in growth of Satsuma orange trees. It seems that chemical and physical properties in examined soils, had a great effect on the efficiency of nitrogen fertilizers.
5. There were the great differences in fruit yield and tree vigor of Satsuma oranges even in each area where the soils of the present experiment were collected. The productivity seemed to be closely related to the available depth of soil and the physical structure and it was difficult to analyze the direct effect of chemical properties.

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Changes in skin color, hardness, soluble solid and acid content of juice and respiration (carbon dioxide production) of Bartlett pears during temporary cold storage and after-ripening were studied in 1964. One lot of fruits was transported from Nagano Prefecture, where fruits were picked on August 11, and another lot from Yamagata Prefecture, where fruits were picked on August 30.
Fruits after-ripened at 20°C softened uniformly and resulting mature fruits had good appearance and high quality, while fruits after-ripened at room temperature softened unevenly, their maturing was delayed, and resulting fruits were inferior in their appearance and quality to those after-ripened at 20°C. Nagano fruits stored for 2 and 3 weeks at 4°C and Yamagata fruits stored for 11 days at 4°C before after-ripening ripened quickly and uniformly. In those fruits there were no differences in number of days to proper ripening, between room temperature and 20°C, or fruits after-ripened at room temperature ripened a little earlier than those at 20°C.
Clear climacteric rise in respiration was observed in the fruits after-ripened at 20°C, while in those after-ripened at room temperature climacteric rise was delayed and its peak was not so high as at 20°C. Respiration rates of fruits which were transferred to room temperature or 20°C after temporary cold storage rose quickly and reached their peaks promptly. In those cases respiration rates were higher at room temperature than at 20°C.
A reason why fruits after-ripened at room temperature were delayed in ripening and softened unevenly was discussed. It was assumed that room temperature, which had been fluctuating mainly between 25° and 30°C, was too high for proper ripening of fruits, and depressed production of a factor, probably ethylene, neccessary for ripening of fruits and enhancing respiration rate. This factor may be accumulated gradually in fruits during temporary cold storage, and when this factor has been accumulated to certain amount in fruits, ripening processes may proceed more quickly at room temperature than at 20°C.

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1. With 3-year-old fruiting Delaware grapes, the effect of night temperature during the ripening process on the maturity and quality of berries was observed. Plants grown in pots were kept in the respective controlled temperature chambers of 15°, 22°, 28° and 35°C at night (6p.m. to 8a.m.), and placed outdoors in the daytime from August 6 to Sept. 10 in 1962.
2. The time of maturity when the berries got full varietal specific color was as follows; August 27 at 28°C, Sept. 3 at 22°C, and Sept. 10 at 15°C, and berries never colored well at 35°C. The pigment content of the skin on Sept. 10 was in the order of 28°≥22°>15°>35°C.
3. The soluble solids content of the juice(refractometer method) increased as the berries matured. The order of the content among the different temperature treatments was 28°>22°>15°>35°C on August 27, 28°=22°>15°>35°C on Sept. 3, and 22°>15° >28°>35°C on Sept. 10. The main kinds of sugars (paper chromatographic method) were glucose and fructose. They were of nearly equal amount at the time of maturity, though glucose was surpassed by fructose with a further advance of maturity.
4. The free organic acid content of the juice (titration method) decreased rapidly with the progress of maturity, the trend being more marked in the treatments of the higher temperature. However, the content became nearly the same in all the treatments when the berries overripened. The main kinds of the free organic acids were tartaric acid and malic acid. The malic acid content decreased more rapidly than the tartaric acid with an advanced maturity and with an increased temperature of treatment.
5. Fully matured berries of Delaware grapes sent from the chief producing districts of Japan were compared concerning their quality in relation to the average air temperature of nearly one month before harvest. As a result, the lower the temperature within a range of 22° and 28°C, the more delayed the maturity, while the more increased the pigment content of the skin, and the more abundant both the soluble solids and the free organic acids in the juice. Furthermore, berries produced in the region of the lower temperature such as Nagano contained less glucose than fructose, and berries which matured in Kagawa under the highest temperature had the least malic acid.

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The investigations were conducted (i) to study the normal development of both macro- and microspores of tomato plants grown at 20°C during the experiment, considering the relation between their developmental stage and the duration expressed as the days before anthesis, and (ii) to observe the morphological abnormalities of tomato flower buds treated with high temperature of 40°C for three hours each in two days at the stages of ten to one days before anthesis. Tomato plants (cv. Fukuju No. 2), sown on March, grown in greenhouse in Tokyo, and treated with high temperature on May 9 and 10, were used as materials.
The development of normal flower buds was as follows.
Development of microspore: Nine days before anthesis, meiosis, pollen tetrads. Seven days before, pollen tetrads separated into pollen grains. Four days before, two-nucleate pollen has germinating pores. Three days before, pollen matured.
Development of macrospore: Eight days before anthesis, meiosis. Seven days before, functioning macrospore (three macrospores degenerated). Six to three days before, macrospore one, two, four, and eight nuclei. Two to one days before, antipodal cells degenerated, synergids pear-shaped, polar nuclei fused into central nucleus.
Both macro- and microspore mother cells in meiosis stages (nine to eight days before anthesis) were easily affected by the high temperature treatment. Pollen tetrads became degenerated, and were deeply stained, but in the samples fixed five days after the treatment, it was observed that their contents became empty and poorly stained. The macrospore mother cells were also degenerated and their developmental stages were delayed.
The injuries of high temperature to both macro- and microspores decreased with the advance of the stage of flower buds. In three to one days before anthesis no morphological disturbance by the treatment was observed in pollen or ovules.
High temperature might not cause any morphological abnormalities to the flower buds younger than meiosis stages.

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In general, composts used for raising seedlings of vegetable crops in hot beds are piled outdoors in midsummer, turned and repiled two or three times in the following seasons and allowed to stand until next early spring to decompose the applied organic materials. It is generally believed that application of organic materials increases soil aggregates, and then improves the physical properties of composting soils. In order to ascertain the changes in soil aggregates during piling, the following studies were undertaken.
1. The sample varying in the soils and applied organic materials were collected at intervals from three locations near Tokyo. In A compost (volcanic ash soil+fresh grass weeds) percentage of aggregates >0.25mm increased markedly after piling. then finally decreased, in B compost (sandy loam +dried rice straw and husk) the aggregates increased progressively, and in C compost (volcanic ash soil + rotted farmyard manure) there was little change in aggregation during piling.
2. In the second experiments, six composts were pilied, which varying in the added organic materials, amount of nitrogen applied and method of piling. In the straw-composts, percentage of aggregates increased accompany with the degree of the decomposing of straw, before long reached its then decreased. In the leaf-mold commaximum, posts, there were little changes in aggregation during piling.
In the straw-compost, to which large quantity of calcium cyanamide was added as a nitrogeneous fertilizer, the decomposition of straw was slow and the time required for maximum aggregation was lengthened.
With respect to piling method, it was evident that the compost for which soil, cutted-straw and fertilizer were mixed well when they were piled, formed aggregates earlier than the one for which soil, non-cutted-straw and fertilizer were piled in layers, but there occured deterioration of aggregates in the former compost by the rapid decomposition of straw.
3. The above mentioned results indicated that the soil aggregate formation or deterioration during piling was affected by types of soils and organic materials, quantity of fertilizer added and methods of piling, and was regulated with the decomposition of organic materials by micro-organisms.

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In order to obtain the physiological data concerning the flower head initiation of cauliflower plants by low temperature, this experiment was carried out with Nozaki-wase grown in the experimental field and with Early Snowball A grown at various temperatures in the phytotron, analysing auxins and gibberellin-like substances in the apical part and chemical constituents in the stem of plants.
1. Seedlings planted early in spring received the effect of low temperature immediately after transplanting, while seedlings planted in summer grew for a while under favorable condition for vegetative growth following the transplanting and then were exposed to low temperature. Thus the latter were larger than the former at the stage of flower head initiation.
The following analytical results were noted with these materials.
(1) Carbohydrates and nitrogen compounds gradually increased with the progress of age and especially soluble sugar was accumulated remarkably in the stem of both plants sown in spring and summer, resulting in the highest level at the stage of flower head initiation followed by a rapid decline.
(2) A temporary decline of auxins, especially in the Rf value of IAA, was clearly shown immediately before flower head initiation in both plants sown in spring and summer.
(3) The content of gibberellin-like substances was small amount at the vegetative stage and increased considerably after flower head induction.
(4) DNA content was fairly constant at the vegetative stage in spite of the different size of seedlings sown in spring and summer, but thereafter gradually increased following flower head induction, while RNA increased rapidly with the progress of age, resulting in a peak immediately before flower head initiation, corresponding with the time of a temporary decline of auxin.
From the analyses of nucleotide components of RNA in apical parts of plants at the vegetative stage and reproductive stage, it was found that the ratio of purine base to pyrimidine base was high at the vegetative stage in contrast to the low value at the reproductive stage.
2. When Early Snowball A seedlings were exposed to 10, 17 and 25°C respectively, the flower headd ifferentiated after five days at 10°C and after ten days at 17°C, but did not differentiate in the Plants grown at 25°C.
Corresponding with those responses to temperature treatment, the following analytical data were obtained.
(1) In the stem of plants grown at 25°C, carbohydrates and nitrogen compounds accumulated gradually, whereas the former rapidly increased and the latter decreased with the decline of treated temperature. And the highest vahle of carbohydrales and nitrogen compounds were shown at the stage of flower head induction of plants grown at each temperature.
(2) It was observed that the gibberellin content considerably increased following flower head induction, in other words, from the 10th day after the exposure treatment to 10°C and from 15 th day to 17°C respectively.
(3) Litlle DNA was found in apical parts of Plants grown at various temperatures during the course of vegetative growth followed by a gradual increase at the reproductive stage.
On the other hand, a rapid increase in RNA was found in apical parts of plants grown at 25°C with the progress of age, whereas 10°C and 17°C treatments did significantly decrease the RNA level, the decrease being earlier and greater with the decline of treated temperature.
3. From the above-mentioned results it may be suggested that the flower head initiation of cauliflower plants is induced by the qualitative conversion of RNA, that is, relative increase in pyrimidine base and decrease in purine base of RNA component due to a temporary decline of auxins in apical pazts of plants by low temperature.

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The authors reported in the previous reports that mixed solution of NAA and gibberellin was more effective on the inhibition of flower bud differentiation in chrysanthemum than NAA alone, and that the inhibitory action of the mixed solution was pronounced under reduced light intensity.
The present study deals with the influence of application time for gibberellin or mixture of gibberellin and NAA on flower bud inhibition. The chrysanthemum plants, var. Shintoa, were given solution of NAA, gibberellin or mixture of NAA and gibberellin during the first four days of each week after the treatment of short day of critical day-length (14h.) was started.
The stems of the plants elongated most vigorously in the third week of short day treatment which was given from the middle of July. The NAA and gibberellin spray made during the third week were more effective in inhibition and promotion respectively of their growth than those made during other weeks.
Budding was inhibited most effectively both by NAA spray and by the spray of a mixture of NAA and gibberellin during the 2nd week of short day treatment. It is likely from this result the cell division for flower initials which just had begun one week after the start of short day treatments, was suppressed by the growth substances applied.
The similar effect of inhibition caused by growth substances was obtained in a case when the plants which were received short day treatment for six to ten days, were shifted under normal long day condition.
NAA spray during the 1st through the 3rd week reduced the number of pistilate flowers. Especially, the result during the 3rd week was remarkable.

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Experiments were conducted to determine the most favorable medium for germination and growth of seedlings on sterilized culture of Cymbidium, The results obtained are as follows:
1. KNUDSON′S C solution or BURGEFF′S Eg-1 solution gives better growth than both KNUDSON′S B solution and tomato juice medium for non-symbiotic germination.
2. Fish soluble medium with pepton added accelerates the growth of protocorms and seedlings of Cymbidium.
3. The growth of embryos is enhanced in existence of KNUDSON′S C solution containing L-alginine or L-asparatic acid but not containing glutamic acid. Of the vitamins used as the additive, riboflavin and ascorbic acid also promote their growth.
4. Potassium salt of l-naphthaleneacetic acid (NAA) in the medium inhibits the germination of seed and growth of protocorms in a short term culture. However, the injection of NAA solution on the medium after the germination resulted in an promotive effect of growth of seedlings. It seems that NAA affects more inhibitory on germination than on later development. It is elucidated by the fact that if NAA solution of lower concentration (0.1-1.0ppm) is given in the medium, it promotes the growth of seedlings in the later stage of growth. Especially in the transplanting medium NAA has a good effect on the growth of seedlings.
5. Extract of silkworm-pupa as the additive stimulate, but extract of globule powder has no effect on the growth of protocorm and seedlings.

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The authors reported that marketable cut flowers of dahlia were obtained in winter season when plants were grown under a favorable day-length of 13 to 14 hours, using young plants propagated by cutting, in the previous paper.
In the present experiments, the effects of mature leaves left at basal positions of the main stem and of the position of the bud from which lateral shoot elongated after pinching, on the growth rate of the lateral shoot and flowering were examined. Lateral shoots at the first or third node were allowed to elongate after decapitation, with 0, 2, 4 or 6 leaves left on the main shoot.
The elongation of lateral shoots from the stem with no leaf was very slow, and their flowering was retarded over 20 days in comparison with flowering of those with leaves. Although there were slight differences, stem elongation and flowering were delayed most in the plants with two leaves among the plants with two or more leaves.
Flowering of the shoots from the first node was earlier than flowering of those from the third node, without reference to the number of leaves on the main stem. Length, weight and number of leaves of the lateral shoot from the stem with two leaves were a little less than those of the lateral shoot from the stem with four or six leaves. On the contrary, length, weight and number of leaves of the lateral shoot from the first node of the main stem without leaves were remarkably great. Length and weight of the lateral shoot from the third node of the main stem were less than those of other lots, except that number of nodes of shoots from third node without leaf was slightly larger.
Judging from the quality of the cut flower, the lateral shoot from the first node was better than that from the third node. There were two flowering periods 75 days apart in the lateral shoots from the third node. The lateral shoots that reached the first flowering period had shorter and lighter stems and a smaller number of leaves than those of shoots that reached the second flowering period. The number of nodes of shoots that flowered in the earlier period was similar to that of shoots from the third node of the main stem with two leaves.
The fact mentioned above suggests that flower primordia are formed in an early stage of development of the lateral bud. And, the lateral shoots from the third node may be just in the inductional stage for flower formation.

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