1. The studies presented here were undertaken to determine the effects of manganese in the nutrient solution and of the defoliation of old leaves on 1-year-old shoots, on the dry weight and manganese contents in each old part which had been produced before the treatments.
2. Thirty, 18-month-old Satsuma orange trees on trifoliate orange rootstocks were transferred to the greenhouse on early of November 1966, and grown in the nutrient solution lacking minor elements. On the 11th in January, 1967, when the growth of the flush started, the trees were cut to 3 shoots and allowed to grow until the treatments were started. On the 20th in May, just before the growth of the second flush started, uniform 24 plants were selected and divided into four groups. Treatments consisted of containing (+) or lacking (-) manganese in the nutrient solution in combination with defoliating or non-defoliating their old leaves. Four trees having new good flushes were harvested from each treatment on the 12th in July and were separated into each part and analyzed total manganese contents.
3. No differences numbers of new leaves on a plant were found, but dry weights of new leaves were reduced by the defoliating of old leaves, resulting in small leaves, compared with the non-defoliating of old leaves.
4. Manganese concentrations of new leaves from plants lacking their old leaves were higher significantly than those of plants having their old leaves in both manganese treatments.
5. Excluding the fine roots, manganese concentrations and absolute manganese contents in the old parts reduced greatly in the non-defoliated plants than the defoliated plants in the minus manganese treatment. While in the plus manganese treatment, absolute manganese contents were higher in almost all parts of the non-defoliated plants than those of the defoliated plants.
6. Above results suggested that the manganes was redistributed from old parts to newly developing parts in Satsuma orange trees grown under manganese stress, and that the manganese concentrations of newly developed parts were influenced by the growth ratio of new parts to old parts. In contrast, under adequate manganese, manganese in the newly developing parts was occupied with newly absorbed manganese as a result of continued distribution rather than redistribution.
7. These confirm the facts in the above field observations.

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The effects of three concentrations i.e., 0.0%, 0.1% and 0.2% of boron sprayed on guava variety‘Allahabad Safeda’in the form of boric acid were studied in Horticultural Garden, College of Agriculture, Banaras Hindu University, during 1966-1968.
Highly significant increase in extension of terminal shoot, number of leaves, leaf area per shoot and significant reduction in leaf chlorosis were recorded under 0.2% and 0.1% respectively. Significant earliness in fruit maturity and increase in yield were recorded with boron spray. The physico-chemical composition of fruits markedly improved but only fruit weight and Vit.‘C’were significantly increased at harvest. The maximum effect was exhibited by 0.1% spray.
Chemical analysis for different nutrients reflected the better balance of constituents in the leaves. There was increase in boron content, dry weight, ash and phosphorus with boron spraying and 0.2% spray gave maximum effect. Potassium content was unaffected with boron treatment. Marked reduction in nitrogen and carbohydrate content was recorded and maximum was exhibited under 0.2% spray.

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It has been reported that arbutin is one of phenolic compounds in bark, leaf and fruit of Japanese pear, and hydrolyzed into hydroquinone and glucose by β-glucosidase. Six resistant and five susceptible varieties were used to determine the relationship between arbutin content and resistance to black spot disease of Japanese pear. As a result, there was no correlation between amount of arbutin content and resistance to black spot disease.
On relationship between leaf age and β-glucosidase activity, its activity was high in young leaf both resistant and susceptible varieties, but not in mature and old leaf in both. β-glucosidase activity was higher in resistant variety than susceptible one. And its activity of resistant variety in very young leaf was 2.3 times more than susceptible one.
By injecting with host-specific toxin produced by fungus into very young and young leaves both resistant and susceptible varieties, β-glucosidase activity was inhibited in susceptible variety, but its activity in resistant one was not.
It was considered that activity of β-glucosidase in resistant variety is one of the factors of resistance to black spot disease of Japanese pear.

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Cucumber seedlings were grown at various intensities of blue and red lights at the constant temperature of 25°C in a phytotron and the hypocotyl length and the distortions in cotyledons were observed.
Spring-cucumbers of South Chinese type except‘Ochiai’form showed a remarkable distortion and were more sensitive to blue light than other groups in hypocotyl elongation, although their hypocotyl length itself was shorter than other groups′.
Summer-cucumbers of South Chinese type showed a slight distortion and their hypocotyl was longer than that of Spring-cucumbers. Summer-cucumbers of North Chinese type except‘Sanjaku’cucumbers showed a slight cotyledon distortion and their hypocotyl was longer than that of Spring-cucumbers of South Chinese type.
Both summer-, and Spring-cucumbers of Cross-bred type in this experiment showed a slight distortion. They had longer hypocotyl than Spring-cucumbers of South Chinese type and were not so sensitive to blue light in hypocotyl elongation as Spring-cucumbers of South Chinese type.
In‘Ao-fushinari’strain belonging to Spring-cucumber of South Chinese type, cultivars of‘Ochiai’form showed a slight distortion, although those of‘Ao-fushinari’and ‘Hyuga’forms had a remarkable distortion.‘Sanjaku’cucumbers of North Chinese type showed a remarkable distortion. They had a shorter hypocotyl than other cucumbers of that and were sensitive to blue light in hypocotyl elongation as Spring-cucumbers of South Chinese type.
Considered these from the standpoint of cucumber pedigree, it is suggested that cultivars belonging to‘Ao-fushinari’and‘Hyuga’forms and to‘Sanjaku’cucumbers owe their character of remarkable distortion in cotyledon and of sensitiveness to blue light in hypocotyl elongation to‘Hanjiro’strain of Spring-cucumbers of South Chinese type.

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The present studies were carried out to ascertain the organ sensitive to daylength condition affecting flower initiation and to clarify the role of the organ in the process of flowering in egg plants.
Results were as follows;
1. The plants whose cotyledons were removed, as compared with the unremoved control plants, bore the first flower at higher nodes. Defoliation from the first to the fifth node tended to lower the node with the first flower. From these, the cotyledons themselves may be sensitive to inductive conditions.
2. The node with the first flower was hightened by removal of a pair of cotyledons and not done by removal of the complementary half or two halves of cotyledons. This indicates that external conditions given to the complementary half or two halves of cotyledons on a plant will have the same effects on flower formation as the entire plant had been accepted.
3. The treatment of cotyledon removal on the second and the fifth day after their expansion tended to raise the number of node with the first flowers. The plants whose cotyledons were removed on the tenth day or more after their expansion bore the first flower at the same node as the unremoved plants. The flowering is apparently promoted by the cotyledon under favorable conditions within ten days after their expansion.
4. The temperature was set at the night temperature of 20°C (warm), and 17°C (cool). The daylength consisted of two groups, namely, 20-hour (long-day), and 8- hour photoperiod (short-day). To clarify the sequence of flowering processes, plants were transferred from long-day and cool or relatively low temperature condition to short-day and warm temperature condition {(LD+CT)→(SD+WT)}, and vice versa {(SD+WT)→(LD+CT)} at varied dates after expansion of cotyledons. Control plants were grown under the condition of (LD+CT) or (SD+WT) during the period of the experiment. Plants were grown under the condition of {(SD+WT)→(LD+CT)} bore the first flower at higher node than those under the condition of {(LD+CT)→(SD+WT)}. Differences of the nodes with the first flower among plants grown under the former condition were not significant.
Floral initiation was delayed by the treatment of long-day and cool temperature condition (LD+CT) for five days after cotyledon expansion. Floral initiation, however, occurred early if plants were grown under this condition for ten days or more after cotyledon expansion.
Differences of the node with the first flower among the treatment periods of ten days or more, were not significant.
In conclusion, the organ perceiving temperature and light especially the light-responsive organ, is the cotyledon in egg plants. Froral induction occurs under long-day and cool temperature conditions for ten days after cotyledon expansion. Thereafter. the response of plants to their environment may be involved in a photoperiodic “after-effect”, resulting in flower developing.

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It is well known that the parasitic activity of root-knot nematodes is considerably influenced by temperatures. This study was done in 1971 to clarify the influence of different temperatures on the level of infestation by Cotton root knot-nematod, Meloidogyne incognita var. acrita and Northern root knot-nematode, M. hapla, and to find out the vegetable crops resistant or tolerant to these nematodes. Results are as follows:
1. In order to secure the relationship between the level of nematode-infestation and the soil temperatures, more reliable data were obtained under the conditions of constant temperatures than under those of alternating temperatures. The trend of maximum soil temperatures in a time series, without taking the average of temperature measurements, served as a measure fitting to investigate the level of infestation under the conditions of alternating soil temperatures.
2. Increase in the level of festation by M. incognita var. acrita and in the degree of injury to plants was found under the conditions of alternating temperatures having the mean of extremes of 32°C.
3. If the amount of infestation by nematodes is observed at the time of visible root-knot formation, the infestations were most severe at a constant temperature condition of 27°C in both nematode species. However a rise in the constant temperature to 32°C remarkably decreased the level of infestation by M. hapla and, contrary to this trend, a full in the constant temperature to 18°C remarkably decreased the level of infestation by M. incognita var. acrita.
4. Among the vegetable crops, tested species resistant to both nematodes were sweet pepper, green soybeen, chinese cabbage, and leaf mustard, and species to relativcly resistant to them was taro. Considerable infestation by M. hapla was observed in the root of watermelon var. Otome.

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These experiments were carried out to establish a method of anther culture of asparagus. Special efforts were made to clarify the effects of developmental stage of anthers, method of sterilization and concentration of growth regulating substances on callus and organ formation. The medium was prepared by adding 20g/l sucrose, 7.0g/l J-agar and growth regulating substances (N⁶-benzyladenine and NAA) to Murashige and Skoog′s medium (MS medium). The cultures were incubated at 25°C under 16 hours illumination (4, 000lux) a day with fluorescent lamps of daylight type. The experimental results are summarized as follows:

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Kroh (1966) reported that self-incompatible pollen grains after being placed for a short time on the stigmatic surface of foreign plants were able to penetrate the self-stigma, in Arabis arenosa and Brassica nigra. She concluded that the cutinase of the pollen was activated irreversibly during the short contact of pollen grains with a foreign stigma. On the other hand, the results of Kanno et al. (1967) with Diplotaxis ercoides and Brassica nigra disagreed to those of Kroh.
In these experiments two cultivars of self-incompatible and cross-compatible Japanese radish, Shogoin and Minowase, were used as materials. Pollination and the transfer of pollen from one stigma to another were carried out at 22°C using a fine needle. Since some of the pollen grains germinated within 35-40 minutes after cross- pollination, the transfer of pollen after self-or cross-pollination was started 20 minutes after the pollen grains were brought on the stigma. Pollen and stigma were combined as follows (after Kroh): I (crossing→crossing), II (selfing→crossing), III (selfing→selfing) and IV (crossing→selfing). The behavior of pollen on stigmas was examined by the following procedure: The pistils were collected 24 hours after pollination, fixed and stained with 0.5 percent lactic-blue for fourhours, differentiated with lactic acid for about 24 hours and finally mounted with glycerine.
The results obtained were presented in Tables 1-3. In the experiment of 1967, the results of combination IV disagreed to those of Kroh (Table 1). Only two experiments, combinations III and IV, were performed in 1968. However these experiments were unsuccessful because of poor technique (Table 2). Through training for pollination technique, the identical experiments were carried out in 1969 and 1971. Table 3 shows that the percentage of pollen germination in combination IV was much superior to that in combination III. Some compatible pollen grains whose tubes penetrated the stigma were found in combination IV, but few in combination III. However the tubes of compatible pollen were generally short. A few emptied pollen grains which had transferred their contents into their tubes were recognized in combination IV.
These results are in agreement to those of Kroh. It seems probable that the inactive enzyme of the pollen is to some extent activated irreversibly, during the short contact of pollen grains with a foreign stigma.

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Effects of hydrogen-ion concentration in the culture solution on the growth of spinachs were examined using gravel culture technique. The degree of acidity of the solution was maintained at pH 3, 4, 5, 6, 7, and 8 by adding HCl or NaOH.
Spinach growth was normal at pH 5, 6, and 7 but downward at pH 3, 4, and 8. At pH 3 and 4 leaves became darker green and at pH 8 they tended toward the occurrence of a yellowish green coloring.
Chemical analysis revealed that calcium and magnesium contents were low at pH 3 and 4, while iron, manganese, and boron contents decreased significantly as pH increased.

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When freesia corms are stored at low temperature (13-15°C) after harvest, the corms do not sprout but consume their food material to form new corms above the old ones. This phenomenon is called pupation-pupa formation, and little works have been done in order to estimate the cause of pupation. The present study was designed to clarify the effect of temperature on induction and process of the pupation for cormlets of‘Rijnveld′s Golden Yellow’.
The results obtained were summarized as follows:
1. When freesia cormlets were stored at different degrees of constant temperature, 13°C was most effective to pupation and the temperatures lower than 2°C or higher than 20°C showed no effect.
2. In the second experiment, the cormlets pretreated with various degrees of temperature (2-21°C) and durations of the treatment (10-50 days) were stored under warm conditions. The chilling pretreatment at 5-17°C was always effective to pupation, and the pretreatment at 9-10°C for 30-50 days was also effective highly and produced large pupa.
The longer the period of chilling the more effective, and the duration of 10 days was seemed to be the lower limit for pupation even with optimum temperature.
The cormlets treated with chilling below 2°C did not form pupa even 50 days treatment. On the contrary, higher temperature than 21°C inhibited the induction of pupation.
3. In the third experiment, the cormlets were treated with chilling at 2-9°C for about 1-3 months and were moved into another thermostat of various degrees of temperature and lastly they were stored for about three months.
In the lots of storage at warm temperature of 19-21°C, pupation was accelerated and large corms were formed. While the pupation of the cormlets stored at the temperature lower than 15°C were delayed, almost no pupation was seen in the lots of 5°C.
4. It seems that there are two thermo-inductive processes (phases) in corm formation of freesia, viz., the process of induction of physiological state for corm formation and the process of development of corm as the thickening growth of stem. It was recognized that the treatment of low temperature especially about 9-10°C was apparently effective for the induction of physiological state for corm formation and warm temperature at about 20°C promoted the development of freesia corm. Consequently the effectiveness of the low temperature for induction of corm formation increased with the duration of treatment within certain limits.
5. On the basis of the results mentioned above, it is estimated that the optimum temperature for corm formation is closely related with the climate of native land of the wild Freesia refracta. There is no doubt that“the acquisition or acceleration of the ability to corm- and bulb-formation by a low temperature treatment”is the general characteristics in the tuberous and bulbous plants which produce the corms or bulbs in early summer, and this phenomenon resembles to vernalization in flower formation.

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1. Flower bud formation in Phalaenopsis amabilis cultivar‘Doris×Does Pueblos’ hybrid was studied.
2. The plants were grown under the ordinary orchid greenhouse at Chuo Agricultural High School, Kanagawa Prefecture, Japan.
3. Flower bud samplings were made at one or two week intervals from Sep. 11 to Dec. 25, 1970.
4. Stages of the flower buds were observed under the stereo-scopic micro-scope by scale stripping method.
5. Inflorescence shoot began to grow on Oct. 20, and the first floret primordium was formed at the sixth to seventh node of the inflorescence shoot, on Oct. 30.
6. Then the flower buds developed to sepal formation stage (Nov. 13), petal formation stage and column formation stage (Nov. 27), pollen sack and stigma formation stage (Dec. 11), and pollen formation stage (Dec. 25). And the first flower bloomed on Jan. 17, 1971.

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Effects of carbon dioxide concentrations on‘Jonathan’and‘Ralls’apple fruits were studied. Fruits were stored in the air mixed with 0, 1, 3, 5, 10 and 20% CO₂ both at 4°C and at 20°C.
Jonathan
At 4°C, yellowing and softening were retarded at the concentrations above 10% and above 5% CO₂, respectively. At 20% CO₂, more decrease was obtained in the oxygen absorption rates and the acidity. Off flavor was found at 10 and 20%. So, the best eating quality was obtained at 5% CO₂. At 20°C, yellowing was retarded at 3-20%, and softening, decreases of the acidity and the oxygen absorption rates were retarded at 5-20%. Off flavor was found at the levels above 5% CO₂.
In 20% CO₂ at 4°C, carpellary tissues browned without cavities (Fig. 3). The flesh below the stem cavity browned and accompanied with the browning above mentioned (Fig. 4). In 20% CO₂ at 20°C, the dry brown spot with the cavity was found on the core line (Fig. 4).
Ralls
At 4°C, yellowing and softening were retarded at the levels above 1% and above 3% CO₂, respectively. Off flavor developed at 3-10%. At 20°C, yellowing and softening were retarded at the levels above 1% and above 3%, respectively. The abnormal flavor developed at 10 and 20%.
In 1-20% CO₂ at 4°C, brownings in the carpellary tissues spread into the receptacle (Fig. 5). The severer were found at the higher CO₂ levels. In 5-20% CO₂ at 20°C, dry brown spots with cavities developed (Fig. 6). The severely browned fruits softened and had the low acidity.
At 4°C, optimum CO₂ levels for CA storage seemed to be 5% in Jonathan, however, unclear in Ralls because of the brownings at the lower CO₂ levels. Discussions were made about the relations between brownings and the temperature.

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The rate of weight loss of Satsuma mandarins (Citrus unshiu MARKOVITCH, cv. Katayama, and cv. Ishikawa) was measured under various wind velocities during curing. The quality of cured fruits was compared organoleptically with that of non-cured fruits during the storage at 7.5°C for 100 days.
1. The rate of weight loss of Satsuma mandarins (cv. Katayama) was not influenced by the wind velocities in the range from 20cm/sec. to 180cm/sec. at 10±1.5°C and 62±2% relative humidity. The rates of weight loss for 6 days of the fruits under wind velocities of 20±2.5cm/sec., 60±7.5cm/sec. and 180±12.5 cm/sec. were 4.19±0.64%, 4.41±1.27%, and 3.98±1.28%, respectively.
2. The same tendency was observed in the rates of weight loss of cultivar, Ishikawa harvested at different times. The fruits covered by double layers of polyethylene film (0.05mm) except the bottom area of 3cm in diameter lost their weight by about 0.7% for 8 days. The rate was reduced to approximately one-seventh compared with non-covered one.
3. The average rate of weight loss of fruits cured under the wind velocity of 20-25cm/sec. was 2 to 3 times as high as that of fruits stored under a very weak wind (below 5cm/sec.).
4. The quality of fruits cured under the wind velocity of 20-180cm/sec. was inferior organoleptically to that of non-cured fruits during storage at 7.5±3.5°C and 90±2.5% relative humidity.
The data indicate that the wind velocity of 20cm/sec., or less must be used for the curing of Satsuma mandarins in order to prevent physiological breakdown and decay as little as possible and to keep the fruits in a good quality during storage.

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The experiments were carried out to clarify the metabolism of glutamic acid (Glu) and γ-aminobutyric acid (γ-ABA) and the changes of their metabolism during the ripening of tomato fruits. As a result of the experiment using L-Glu-¹⁴C (U) and γ-ABA-1-¹⁴C in tomato slices, Glu was converted into γ-ABA by decarboxylation and γ-ABA was metabolized into the acids in TCA cycle. The ¹⁴C-activity incorporated in the acids from γ-ABA-1-¹⁴C was higher in succinic and malic acids. This incorporation rate was higher in immature stages and decreased with ripening.
These results suggested that the metabolic pathway of Glu to succinate via γ- ABA (and succinic semialdehyde) existed and this pathway might play an important role in ripening process of tomato fruits as a by-pass of the α-ketoglutarate-suc cinate step of the TCA cycle.

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A study was conducted to determine the effects of low temperature on the changes of the phenylalanine ammonia-lyase (PAL) activity of pepper seeds and the ethylene production of pepper fruits. Especially, the relation between the ethylene production of pepper fruits and the PAL activity in the seeds was discussed.
1. The activity of PAL in the seeds as a key enzyme of biosynthesis of phenyl- propanoids increased to a maximum after 18 hours of low temperature storage (1°C) and then showed a constant level till 48 hours, but it did not increase in the lot of 20°C.
2. The rate of ethylene production by pepper fruits increased before the increase of PAL activity during the low temperature storage. The activity of PAL in the seeds was rapidly enhanced by the treatment of 300ppm ethylene at low temperature but not by the treatment at 20°C.
3. It is emphasized that ethylene may be a factor concerning the increase of the PAL activity of pepper seeds under the stress of low temperature.

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