Somatic chromosome numbers of the cultivated and wild butterburs collected from various localities of Japan were counted in order to elucidate the origin of cultivars, and relationships between polyploidy and their characteristics or geographical distribution were studied.
1.“Aichiwasebuki”and“Mizubuki”, two commonly grown cultivars, were found to be triploid with 2n=87, and the gigantic cultivar called“Aichiwasebuki”, subsp. giganteus KITAM., was found to be diploid with 2n=58. The local strain“Akitaaobuki”was consisted both of triploid and diploid plants. (Table 1, Figs. 1, 6, 7.)
2. In the wild butterburs, 437 diploid plants were collected from 142 different habitats and 191 triploid plants from 62 habitats. Gigantic wild butterbur“Akitabuki”which distributed in Hokkaido and Tohoku districts were found to be diploid with 2n=58 without exception. Diploid and triploid plants showed a marked difference in the geographical distribution. That is, diploids distributed widely in any localities of Japan, while triploids which were not found in Hokkaido district showed a gradual increase toward south. In Kyushu district, southern part of Japan, the number of triploid plants collected was larger than that of diploid ones. (Table 2, Figs. 2-5, 8-10, 11)
3. There is no possibility of the triploid plants being hybrids between diploid and tetraploid plants, since no tetraploid ones have been discovered both on cultivars and wild butterburs. The interspecific hybridization may be also impossible, because only one species of genus Petasites has been found in Japan. Consequently, the triploid butterburs must have been derived form fusion between unreduced and normally reduced gamates of diploiod butterburs, and the triploids are presumed to be autotriploid.
4. The completely sterile male and female plants were found to be triploids and differed morphologically in the individual floret or inflorescence from diploid plants. Namely, the style of triploid male plants was markedly shorter than that of diploid ones and the anther did not open. Of triploid female plants, the ovary and pappus did not develop at all, and the inflorescences or individual floret turned brown in appearance in an early stage of its development. (Figs. 13, 14)
5. The sex expression of butterburs was not influenced by environmental factors and in spontaneous triploid plants sex expression was not related to polyloidy. In the triploid cultivars, however, more female plants were found, which suggested that more female plants has been introduced to cultivation accidentally and propagated vegetatively.
6. Triploid butterburs, both cultivars and wild ones, were distinguished from diploid ones by their earlier sprouting, larger leaves and more vigorous growth habit. (Table3, Fig. 12)
7. The results mentioned above suggested that cultivars of butterbur have been derived from triploid wild plants and not from diploid ones.

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1. Effect of thermoperiods on the vegetative and reproductive response.
Tomato seedlings were grown and tested under each of six thermoperiods: all combinations of day temperatures (24°C and 30°C) with night temperatures (17°, 24° and 30°C).
High day temperature induces the vigorous growth followed by the acceleration of the flower differentiation and its development, whereas higher night temperature restricts the plant growth, being followed by the retardation of the flower bud differentiation, the increase in the number of leaves to the first inflorescence and the decreased number of flowers with the retardation of their developmental growth.
It may be concluded that the most favorable thermoperiod for the plant growth, flower formation and fruit production is day temperature 24°C: night temperature 17°C
2. Effect of low night temperature at various stages of plant growth on flowering behavior.
Tomato seedlings were subjected to the low night temperature of 17°C at various stages of plant growth, and after the treatment the night temperature was raised to 26°C. During the course of this experiment the day temperature was maintained at 24°C.
It was found that exposure of seedlings to low night temperature for at least 2 weeks just after cotyledon expansion resulted in the least number of leaves to the first inflorescence.
The flower numbers in the first, the second and the third inflorescence reach the maximum respectively by three, five and seven week-exposure to low night temperature from the cotyledon expansion.
These results show that the flower formation of the respective inflorescence needs a long temperature treatment previous to the morphological flower bud formation. This is determined by the observation, under the microscope.
3. The stem width and the temperature as related to the flower differentiation.
In general, the first inflorescence differentiates at the time when the stem diameter just below the cotyledon reaches 2.4-2.8mm, but it does not always follow that the seedlings grown under any environmental conditions form flower buds when they reach this critical size. Lower night temperature stimulates the earlier flower formation, the vegetative growth being somewhat suppressed. The flower bud differentiation is not necessarily associated with the sum of the daily mean temperature from the cotyledon expansion.
4. Relationships detween the flower formation and chemical constituents in tomato seedlings.
The results of the chemical analysis in the top of seedlings grown under the various combinations of day and night temperature for 50 days from the cotyledon expansion show that the higher the content of carbohydrates, especially total sugars and nitrogen compounds especially protein, the greater the increase in the total number of flowers up to the third inflorescence. The flower bud differentiation and the flower bud development are favored by a high level of carbohydrates and nitrogen compounds.
It is concluded that the seedlings, having been grown under the favorable thermoperiods, are heavy in weight in contrast to the plant height, high in total sugar and protein contents, bloom earlier and produce a high yield.

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1. Influences of deep plowing on growth and yield of several vegetable crops and effects of subsoil condition which counteracts the favorable effect of deep plowing were investigated on vegetable crops comparing with some cereals and forage crops, in order to know their adaptability to the cropping systems under deep plowing.
2. The studies were performed in the field of volcanic ash soil. The crops investigated were tomato, cucumber, pumpkin, Chinese cabbage, Welsh onion, Japanese radish, taro, sweet potato, soybean, upland rice, corn, and barnyard millet.
3. It was recognized that deep plowing had an favorable effect on growth and yield of most vegetable crops and it was more effective with heavy application of fertilizers. The raw subsoil was unfaborable to growth and yield of cereals and forage crops, but most vegetable crops with heavy fertilization were not so sensitive to the inhibition caused by subsoil. Moreover, most vegetable crops showed excellent growth and yield on the subsoil which was improved by exposing to frost action in winter and by heavy application of fertilizers.
4. In pot-cultur the growth of most vegetable crops was inhibited in the poor subsoil, but it was vigorus in the fertile subsoil with heavy fertilization. Some of them showed rather better growth in subsoil than in topsoil with the same amout of fertilizers.
5. It was made clear that the crops which gained high yields under deep plowimg were not so affected by poor nutritive condition of subsoil and the yields of vegetable crops did not decrease remarkably in the raw subsoil when it was heavily fertilized.
6. Moreover, it was suggested that the sensitiveness for Al toxity and deficiency of nutritive elements, especially of phosphorous, was concerned with the adaptability of crops for subsoil conditions.
7. After all, it was concluded that most of vegetable crops showed a good result under deep plowimg because their roots developed well and the absorption of nutrients became active in response to good soil aeration after deep plowing, and also unfavorable conditions of raw subsoil could be overcome by the heavy application of fertilizers. It was also made clear that they were adapted to the cropping systems under deep plowing.

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The experiments were carried out to ascertain the influence of storage temperature and harvest time on the chemical quality and pigment contents of fruits from 1959 to 1961 at the Agricultural Faculty, Shinshu University. The varieties used were Kurihara in 1959 and Mitsuoka in 1960 and 1961.
1. Fruits were harvested on the 38th day after flowering, and were stored at 15°C, 22°C, or 30°C. Control fruits were allowed to mature on plant. The number of days from flowering to coloring was smaller for the fruits stored at 30°C, and larger for the fruits stored at 15°C, than those matured on plant. Acidity of the fruits stored at 30°C was the highest of all. As to pigment contents, the fruits stored at 22°C contained most and those stored at 15°C contained least lycopene than those stored at other temperature.
2. Fruits were harvested on the 15th, 25th, 35th, 45th and 55th day after flowering, and were stored at 25°C. The number of days from flowering to maturing was smaller when harvested earlier. Acidity of fruit was higher in early harvested fruits and the sugar content was greater in late harvested fruits. Lycopene contents were larger in fruits harvested on the 15th day after flowering than other fruits, while smaller in fruits harvested on the 35th day after flowering. A similar tendency was observed for carotene and xanthophyll contents.
3. Fruits were harvested on the 38th day after flowering, and were stored at 35°C, 30°C or room temperature (23-28°C) for 16 days. Furthermore, each group of fruits was stored at room temperature (23-28°C) for 7 days. Viscosity of juice from fruits stored at 30°C was larger than that from other fruits, and it was the same for those stored at room temperature for 7 days. Lycopene contents were small in fruits stored at 35°C, and fruits at room temperature contained more lycopene than other storage fruits. But fruits stored at 35°C, followed by storage at room temperature for 7 days produced lycopene. Carotene and xanthophyll contents were greater in fruits stored at room temperature and less in those stored at 35°C.

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The growth and flowering of cucumber plants after treatments with BCB were detailed in this paper. The treatment was consisted of one application of 250ml of BCB solution at the concentration from 10^-2M to 10^-3M, poured into the soil of 1/5000 are WAGNER'S pots soon after the expansion of cotyledons.
1. With regard to BCB treatment, the stem elongation of cucumber plant was inhibited and more lateral shootings and greener and crapier leaves were observed.
2. With regard to BCB treatment, the node locations of the first female flower and the first continuous females were lowered, and the number of female flowers per plant increased as compared with that of the control.
3. The first flowering of femaler flower and the harvest of first fruit were accelerated by BCB treatment, and the node location of the first fruit was also lowered as compared with that of the control.
4. With regard to BCB treatment, the node location of male flower was raised, a little, and its flowering was also retarded a little as compared with that of the control.
5. After being treated with BCB for only two weeks, transplanted cucumber plants were influenced in the same way as observed in a non-trans plantation test.

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The investigations on manganese deficiency and its control were carried out from 1955 to 1957 on different kinds of citrus growing in Kanagawa Prefecture.
The manganese deficiency symtoms were clear in June when the spring-flush leaves had reached the full size. The interveinal tissues of the leaves turned yellow, leaving a band of green tissues on both sides of the main veins and the mid rib. The contrast in the color of the main veins and adjacent tissues with the interveinal chlorotic portion was not so clear as in zinc deficient leaves. Such leaves were observed throughout the tree, irrespective of the directions in which the orchards were sloping.
The severity of manganese deficiency seems to vary from variety to variety, i.e., Naruto (C. medioglobosa Hort.) and Natsudaidai (C. natsudaidai HAYATA) showed the severest symptoms, Unshiu (C. unshiu MARCOV.) showed them moderately, while early Unshiu and sweet oranges were slightly affected.
Manganese content in spring-flush leaves increased till August, and thereafter remained fairly constant. Leaf analyses were done in order to find out the manganese content of leaves in 150 Unshiu orchards located in Kanagawa Prefecture. Close relationship between the severity of deficiency symptoms and the manganese content of leaves was recorded. All orchards with leaf manganese less than 15ppm on dry weight basis showed the deficiency symptoms, and 77 per cent of the orchards with leaf manganese less than 20ppm also showed these symptoms.
Manganese content in citrus leaves of Kanagawa Prefecture were comparatively lower than those of the other districts, i.e., 71 per cent or more of the orchards in this Prefecture had manganese content lower than 25ppm on dry wight basis. Manganese deficiency symptoms were found in 67 per cent orchards on volcanic ash soils, where average leaf manganese content was 16.01ppm; in 27.3 per cent of the orchards on volcanic gravelly sandy soils the average leaf manganese content was 20.91ppm; and in 36.8 per cent of the orchards on gravelly clay soils it was 21.5ppm.
Contents of different elements in leaves collected from 100 orchards in 1956 ranged as follows; nitrogen, 2.88-4.14 per cent; phosphorus, 0.14-0.24 per cent; potassium, 0.762-44 per cent; iron, 95-375ppm. A positive correlation was noted between manganese and phosphorus contents in the leaves and it was statistically significant at 1 per cent level.
To contral manganese deficiency, one or two sprayings of 0.4 per cent solution of manganese sulfate before the leaves of spring-flush reached the full size were found effective. Mixture of lime and the above solution appears to be less effective in controlling the manganese deficiency.
The soil applications of manganese fertilizers showed no favourable effect on the plants. Foliar applications of manganese to the deficient trees increased manganese content in young spring flush leaves sampled a year after spraying as compared with leaves of the same age from unsprayed trees.

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In an inoculation experiment of P. digitatum against orange fruits, when phosphate buffer solutions of different pH, ranging from pH 2 to pH 8, were used as the media for spore suspension, affected area (macerated area) developed rapidly with the acidic spore suspension, while slow development was resulted with neutral to alkaline spore suspension.
Spore germination, mycelial growth and PG activity were more vigorous in weakly acidic (pH 4-5), and no relationship was observed between the growth of the fungus and the development of affected area. Consequently it was concluded that the factor governing development of the affected area seems primarily to be acids produced by the fungus, and not to the fungal growth itself or its PG activity.

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A long term experiment on the effect of application of green manure on Satsuma orange has been set up, and the results of the effects of treatments on yield, tree growth, and soil properties were previously reported. This report deals with the results of their effects on the mineral composition of leaves.
1. Analytical results of leaves sampled by the ordinary method from 1951 to 57 revealed that there were no differences in nitrogen, phosphorus, and potassium contents of leaves among 100%, 50% and 0% green manure plots. Calcium and magnesium contents were higher in leaves of the plots receiving larger amounts of green manure (100 and 75 plots).
2. Analysis of both new and old leaves was carried out in August of 1960. It was impossible to find out significant differences in nitrogen, phosphorus and potassium contents of leaves among 100%, 50% and 0% green manure plots, because of large deviations of contents of those elements even in the same plot. Calcium and magnesium contents in the leaves of 100% plot were significantly higher than those of 0% plot, and those of 50% plot were intermediate between those of 100% and 0% plots, or rather close to those of the plots receiving a larger amount of green manure.
3. Analysis of leaves sampled monthly from April to September of 1961 showed that difference was scarcely found in the contents of nitrogen, phosphorus and potassium of new leaves between 100% and 0% green manure plots. In old leaves, there were slight differences in phosphorus and potassium contents from April to July, but these differences disappeared in August or September.
4. It was impossible to find any correlation among yield, tree growth, quality of fruit juice and N, P or K content of leaves, while there were significant correlalions between citric acid content of fruit juice and calcium content of leaves, and also between exchangeable calcium content of soil and calcium content of leaves.

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1. A small amount of alcohol was added to the solution in which pollen of pear, apple and persimmon were suspended for the purpose of a intaining their viability. This solution was tested under laboratory of field condition.
2. In the case of pear, 7% alcohol added to the suspension inhibited pollen germination in suspension and was effective to maintain its viability. A particularly favorable result was obtained when the alcohol sucrose suspension was used.
3. The germination percentage of apple pollen was quite low in the suspension containning 5% alcohol during 2-3 hours after pollen was immersed, and a high percentage of pollen germination and good growth of pollen tube were observed on the germination media.
There was no difference in the set percentage of Golden Delicious apple between the flowers pollinated with mixed pollen of American Summer Pearmain and McIntosh varieties suspended for 3 hours in the solution and those pollinated with intact pollen. And no significant difference in the number of seeds per fruit was observed.
4. The pollen of persimmon in the suspension containing 5% alcohol showed a low percentage of germiation in the solution and a high per centage of germination and vigorous growth of pollen tube on the media. The most suitable time for using the suspended pollen for pollination is within one hour after the suspension is prepared. The pollen suspension sprayed one hour after the preparation showed a similar degree of fruit set as the intact pollen.

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1. A root promoting substance (or substances) was demonstrated in the leaves of Portulaca. This substance moved from leaf to the cut end of stem cutting after the stem was cut.
2. The substance moved more slowly from leaf to stem in darkness than in light, but the movement of substance itself doesn't require light.
3. The rooting substance was detected in higher concentration in the leaves just after cutting, and decreased there after, transferring to the base of stem.
4. Root promoting powers of sucrose, IAA, IBA, 2, 4, 5-TP and kinetin were compared with that of the substance in Portulaca leaves, and their similarity to the substance was discussed.

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