The relationship between seeded berry growth and endogenous auxin and abscisic acid-like activities in Delaware grape was studied.
1. The growth of seeded grape berry showed a typical double sigmoid curve, and was greater than that of GA-induced seedless grape berry.
2. There was a close relationship between high activity of endogenous auxin in berries and the rapid growth rate in early stage (Stage-I).
3. The concentration of endogenous abscisic acid-like inhibitors in the grape berries was low during rapid growth of the berries in stage-I and increased rapidly thereafter until veraison.
4. The application of naphthaleneacetic acid retarded ripening of the seeded grape berries. On the contrary, the applications of abscisic acid, gibberellin (GA₃) and benzyladenine did not affect ripening of such berries.

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Effects of summer water potential (ψ) of potted satsuma mandarin (Citrus unshiu MARC.) trees on fruit characteristics were studied.
1. When ψ (ψ_max) before sunrise were controlled at about-9 bars for 15 (S-9 bar) and 30 days (L-9 bar) in summer, fruit size and weight at harvest became much smaller and coloration of such fruits was much retarded compared with other treatments.
Water potential and diffusion resistance of sun leaves between 1:00 and 3:00p.m. on clear days in S-9 bar and L-9 bar (which fruit growth may be considered to stop) were -19 to -20 bars and 19.4 sec/cm, respectively.
2. In mature trees, water potential of shade leaves and diffusion resistance of sun leaves between 1:00 to 2:00p.m. at which fruit growth nearly stopped, were -16.4 bars and 16.7sec/cm respectively. These values were similar to those in the potted trees, because ψ of sun leaves is usually about 3 bars lower than ψ of shade leaves.
3. As a result of rewatering after severe water stress (i.e. ψ_max -12.2 bars), fruit growth was accelerated transitorily to a higher rate and expansion continued throughout the day. Our data suggest that rapid growth after rewatering is caused by factors aside from the resumption of contraction during the imposed drought.

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With a differential transformer, changes in leaf thickness of one-year-old potted Natsudaidai seedlings were observed throughout the year. The cyclic fluctuations of leaf thickness were at first slight but became noticeable in the middle of May. During the summer season, the amplitude was increased more. In early December, however, the rhythms became irregular with depressed fluctuations and finally disappeared when the season advanced. It was also observed that the amplitude of cyclic fluctuations quickly responded to changes in the carbon dioxide concentration in the air, i.e., the amplitude increased with increasing carbon dioxide concentration up to about 1, 000ppm. On the contrary, when the carbon dioxide concentration was lowered to that of the normal air, the original magnitude was recovered. Such responses of the leaf to changes in carbon dioxide concentration were not observed in the period from winter to spring. From the results obtained, it was postulated that root activity might considerably affect stomatal movement.

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In many vineyards of horizontal trellis, defoliation due to leaf-yellowing often occurs at the basal portion of shoots in early summer. This disorder seems to be partially caused by low light intensity on this portion.
1. In the Delaware vineyards, light intensity at the apical portion of shoots is higher than the basal portion. The leaves on the basal nodes receive a light intensity of 10% of full sun-light during mid June to late August. Defoliation was therefore greater in the basal portion of shoots.
2. When a whole shoot of a young"Delaware"vine was darkened or shaded, defoliation due to browning appeared at the apical portion of the shoot. In contrast, if only the basal portion was shaded, defoliation due to leaf-yellowing was observed at the basal portion of the shoot as seen in the commercial vineyards. There was no difference in the degree of defoliation of the apical or basal portion between bearing and non-bearing shoots.
3. In young"Delaware"vines, if the basal portion of the shoot was shaded, defoliation of the basal portion was promoted by basal application of GA₃ 50ppm and NAA 100ppm, but inhibited by BA 50ppm. In the Campbell Early vineyards, pinching and cutting back of lateral shoots were effective to prevent such defoliation.
4. In the"Delaware"vines shading of the basal portion of the shoot sharply decreased photosynthetic activity of the leaves in this portion, and increased respiration of the leaves in the apical portion. Carbohydrate content of the leaves was less in the shaded portion. Furthermore, the translocation of ¹⁴C was greater in the leaves of the apical portion receiving high light intensity than in the leaves of the shaded basal portion. From these results, early defoliation of grapevines caused by low light intensity seemed to be attributed to the competition for carbohydrates between the leaves of these two portions.

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A long-term preservation of germplasm of fruit trees is becoming increasingly important. This study was designed to develop a routine method for long-term preservation of apple dormant buds in liquid nitrogen. One-year-old twigs of apple (Malus pumila Miller var. McIntosh Red) were collected in late December and were subjected to an artificial hardening regime which consisted of holding samples at -3°C for 20 days, -5°C for 5 days and -10°C for 3 days to induce maximum hardiness. After hardening the twigs enclosed in polyethylene bags were cooled at 5°C increments each day to -30°C and then to -90°Cin 10°C increments at two hours intervals. At selected test temperatures during this procedure, twig samples were removed from the freezer aftr 16 hrs and thawed in air at 0°C.
In apple twigs, major differences between the hardiness of different tissues were observed. The least hardy tissues are the xylem and pith which are marginally hardy to -40°C. The cortex and leaf buds are most hardy tissues, resisting to -90°C. Twigs prefrozen to different temperatures from -15 to -50°C were immersed in liquid nitrogen for 2 hrs, and were then rewarmed slowly in air at 0°C. In the twigs prefrozen to -40°C, little or no injury was observed in the leaf buds and cortex. When the leaf buds from the twigs immersed in liquid nitrogen for 2 hrs were grafted on the two-year-old seedlings, most of the buds normally developed and continued their shoot growth. Thus, this prefreezing method is applicable to the long-term preservation of leaf buds of apple twigs in liquid nitrogen.

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The variations of flower types and the characteristics of berries derived from each flower type were observed in Muscat Baily A, a hybrid between Baily X Muscat Humburg. The effects of flower type on the GA-induced seedlessness were also observed.
Conversion of flower type was attempted by the prebloom application of 6-benzy-ladenine (BA), which is known to induce sex conversion in male clones of Vitis species.
1. This cultivar usually shows variations in the size of female organs in bloom. So, the flower types were classified into three types: perfect-hermaphroditic flowers (male and female organs develop completely), imperfect-hermaphroditic flowers (male organs are normal but female ones are incomplete), and male flowers (lack of female organs). The frequency of male, imperfect-and perfect-hermaphroditic flowers was proved to fluctuate year to year and by the method of pruning.
2. Removing all male flowers, flowers of each of the remaining two types were retained in each cluster and allowed to set. Imperfect flowers displayed poorer berry set, smaller berry size and more seed number than perfect ones. By GA treatment, perfect flowers produced more seedless berries than imperfect ones.
3. The development of pistil was promoted by BA application 2-3 weeks before anthesis, which increased the frequency of perfect flowers, while by the application 4 weeks before anthesis, the frequency of imperfect ones was increased. The ratio of seedless berry formation was increased by GA in combination with the former BA application, especially remarkable with BA application 2 weeks before anthesiswith 125, 250ppm (above 95 percent), while by GA in combination with the latter, the ratio was decreased.
4. Therefore, it seemed that the occurrence of imperfect flowers is responsible for the ratio in GA-induced seedless berry formation in this cultivar.

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Eight species of vegetable crops were grown in solution culture in order to investigate the effect of potassium and calcium concentration in the nutrient solution on manganese toxicities in vegetable crops. Manganese was supplied at levels of 0.5, 30, and 100ppm. At each manganese level potassium or calcium was supplied at rates of 2, 6, and 18me/l. The pH of the nutrient solution was adjusted to 5. Plants were grown under different treatments for about three weeks.
1. Manganese excess induced interveinal chlorosis on upper leaves in bean, eggplant, pepper, and spinach, and marginal chlorosis on lower leaves in cabbage, lettuce, and celery. In Welsh onion chlorosis was induced on lower leaves. Increasing the supply of potassium and calcium reduced the severity of manganese-induced chlorosis. This beneficial effect was generally more marked with calcium than with potassium.
2. Increasing the supply of potassium and calcium was effective in alleviating the growth reduction of vegetable crops due to manganese excess. This effect also was more marked with calcium than with potassium.
3. With increasing manganese level in the nutrient solution the manganese concentration in leaves of vegetable crops increased. Increasing the supply of potassium and calcium inhibited excessive accumulation of manganese in leaves. The influence of calcium was stronger than that of potassium. In any of the vegetable crops tested, regardless of potassium and calcium treatments, manganese concentration in leaves was closely related to manganese toxicities; the more the accumulation of manganese in leaves increased, the more the severity of manganeseinduced chlorosis and growth reduction increased.

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Cabbage plants were water-cultured under a combination of 4 levels of magnesium (0, 5, 25, 125ppm) and calcium (4, 20, 100, 500ppm), and the effect of the elements supplied on the growth and nutrient status of the plants was studied.
The dry weight of a whole plant (plant-top+roots) and inner leaves increased with increasing levels of Mg from 0 to 125ppm when the concentration of Ca in the culture solution was high, whereas it decreased at higher levels of Mg when the concentration of Ca was low. The contents of Mg and Ca in the plants increased with increasing levels of each element, and an increase in the content of one element caused a decrease in the content of the other element. The plants high in Mg or Ca were liable to suffer from deficiency injury involving Ca or Mg. The critical contents of Mg and Ca in outer leaves resulting in deficiency injury were about 0.1 and 1.3% on a dry matter basis, respectively.
A suitable range of the Ca/Mg content ratio as well as adequate contents of Mg and Ca in each organ is considered to be favorable for the growth of cabbage plants.

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This experiment was carried out to study the thickening of turnips, by morphological, anatomical and histochemical methods.
The process of the elongation and thickening of hypocotyl was observed from the morphological point of view, the anatomical changes of hypocotyl from the anatomical method, and the changes of the content of mono- and polysaccharide, nucleic acid and lignin from the histochemical point of view.
The results were as follows: The elongation of hypocotyl stopped by the 6th leaf stage in all varieties used, while the beginning of thickening depended upon the variety used. In Yorii-kabu and Kanamachi-kokabu, thickening began at the 4th leaf stage. And at the 6th leaf stage, the thickening of the hypocotyl was visible to the naked eye. But, Koiwai-kabu did not begin to thicken even at its 10th leaf stage.
Through the observation of the thickening of turnips, it was found that thickening began from the central part of hypocotyl and after that the thickening of the upper and lower part began. On the other hand, in the case of radishes, the main root was the first to thicken.
In anatomical studies on the thickening of turnips, the following was observed: New phloem was formed at the xylem parenchematose tissues, which were situated inside the cambium ring which had been formed by about the 4th leaf stage, and became active. These active cells of the new phloem cut the cambium ring, and as the result, the tissue of the hypocotyl began to thicken. This phenomenon was not observed in other Brassica (B, pekinensis, B. oleracea, B. juncea…).
In the histochemical observation of the hypocotyl of turnips even after the 4th leaf stage, the reaction of mono- and polysaccharide and nucleic acid was stronger than in those of non-thickened varieties. On the contrary, the hypocotyl of turnips scarcely showed the reaction of lignin, while the hypocotyl of those which had non-thickened varieties showed a very remarkable reaction.
In another observed point of radishes and turnips, the cortex which had formed at their germinating stage was cracked and dropped out when their thickening began. It may be safely said that this phenomenon occurred because primary cortex could not stand the physical changes (thickening) of the inside tissue, which was confirmed both anatomically and histochemically.

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The Indian Lotus, Nelumbo nucifera GAERTN. has two kinds of leaves. They are the standing leaf that stands at the surface of the water and the floating leaf that rises to the surface of the water. The first leaf which is formed in the first node of the main stem growing out of a terminal bud of the seed-rhizome (a storage stem) becomes the standing leaf, or the floating leaf. What conditions will make the first leaf in the first node of the main stem the standing leaf, or the floating one?
The present investigation is aimed at the effect of the amount of applied fertilizer (zero, standard, and double) and shading treatment with cheesecloth (roof type shading and tunnel type shading) on these leaves. The result may be summarized by the following points:
1. Both at the control and at the roof type shading, the first leaves formed in the first node of the main stem have become the standing leaves. But by the amount of the standard and double fertilizer applied with the tunnel type shading, they have become the floating leaves respectively, where the relative humidity was remarkably higher than other treatment.
2. The thickening grade of the cell wall, that composes the hypodermis in the petiole of the first leaves of the main stem, was more remarkable in the standing leaves than in the floating leaves. The Phloroglucin Hydrochloric Acid Reaction was in proportion to the thickening grade of the cell wall; namely in the remarkable thickening in the petiole of the standing leaf the Phloroglucin Hydrochloric Acid Reaction was remarkable. Slight thickening at the petiole of the floating leaf was not remarkable.
3. The thickening grade of the fibrous cell, that composes the hypodermis in the petiole of the first leaves of the main stem, was more remarkable in the standing leaf than in the floating leaf. The morphology of the fibrous cell in the petiole was almost the same as in both the standing leaf and floating leaf. The thickening of the fibrous cell in the standing leaf was remarkable and in the floating leaf it was slight. It was found that the histological difference of the standing leaf and floating leaf depended upon the thickening grade of the fibrous cells.

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Relationships among fruit weight, number of seeds and several characteristics, such as number of locules and weight per seed, which was related to the two characters, fruit weight and number of seeds, were statistic-genetically studied by a variety test consisting of ten varieties which were grown under five conditions of environment in order to elucidate the role of seed on the tomato fruit.
Higher positive genotypic correlations were recognized among fruit weight, number of seeds and locules, and positive genotypic correlations seemed to exist between days to flowering and fruit weight, number of seeds, seed weight per fruit, respectively. On the other hand, multiple regression analysis was conducted upon some characteristics, in which fruit weight was assigned to dependent variate and number of seeds, and locules, weight per seed and days to flowering were selected as independent variates. These results revealed that the number of seeds (seed weight per fruit) had a very close genetic relation with fruit weight, and the number of locules followed secondly. It proved, however, that the close relation between the number of locules and fruit weight was combined without any influence on other characteristics such as the number of seeds and days to flowering, while the influence of the number of seeds on fruit weight was divided into the two path ways, that is, the indirect effect by number of locules, days to flowering and weight per seed, and the direct effect by the number of seeds itself.
Positive genotypic correlations seemed to exist in the two combinations of weight per seed and percentage of seed germination, and fruit weight per seed and the number of locules. On the other hand, negative genotypic correlations seemed to exist between the number of locules and weight per seed, percentage of seed germination, respectively.
Environmental correlations were generally smaller than genotypic correlations and also fewer in the number of combination in which correlation was found. A positive environmental correlation was found between fruit weight and number of seeds (seed weight per fruit), but not found in the following combinations: the number of locules and fruit weight, and the number of locules and number of seeds (seed weight per fruit). Also, the effect of developed and undeveloped seed on fruit weight was discussed.
In this study the within-variety correlation between fruit weight and number of seeds again showed varietal difference. Furthermore, it was inferred that there were two kinds of varieties which had a comparatively stable or instable correlation under several environmental conditions.

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The results of trials with strawberry cv. Donner that was given a flat cover of a white cheesecloth of about 85% permeability for the winter season after being planted in the open in October, indicated that the covering particularly improved leaf production rate and leaf area and this consequently increased the fresh and dry weights of covered plants. The relative differences of plant growth between flat covered plot and exposed one were reflected in their carbohydrate contents and fruit yields thereafter. 36.1 fruits per plant were obtained in the flat covered plot and 28.1 in the exposed one, respectively. However, the average weight per fruit in the former was less as compared to that in the latter.

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Effect of light and plant growth regulators on anthocyanin formation of seedlings of waterpepper, Polygonum hydropiper L. was investigated.
1. The seedlings were irradiated from daylight fluorescent lamps and then incubated at 20±3°C in the dark for 2 days. The anthocyanin content in the seedlings was remarkably increased by 15-min irradiation. Furthermore, by irradiation over 15-min, the anthocyanin content was gradually increased in proportion to the length of irradiation.
2. Maximum of action spectrum for anthocyanin formation was 660nm.
3. IAA and GA₃ application after irradiation markedly inhibited anthocyanin formation, but 2, 4-D and NAA had no effect.
4. B-9 and CCC application after irradiation promoted anthocyanin formation, but MH had no effect. B-9 application before irradiation did not promote anthocyanin formation.
5. BA application before and after irradiation markedly promoted anthocyanin formation.
6. In the practical culture of seedlings of waterpepper, soaking the seeds in BA solution for 4 days before germination improved pigmentation. Such treatment with BA was effective to promote pigmentation even under adverse conditions such as high temperature or low light intensity.

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The problem of whether species or cultivars of seeds of Allium spp., cucumber and melon, carrot, pea or garden bean could be determined by analysis of electrophoretic patterns of seed protein or seed enzymes was studied.
Electrophoresis was carried out with acrylamide gel disc.
The results obtained are summerized in Table 1.
1. Allium species: Four species of Allium were distinguished from one another by electrophoretic patterns of protein, LDH, GDH, SDH, α-GPD and CA, provided that the distinction of Welsh onion and leek or A. tuberosum was not clear in zymograms of α-GPD, and also that the distinction of Welsh onion and onion was impossible in zymograms of CA. Cultivar Hana-nira(flower-eating cultivar) in A. tuberosum showed different electrophoretic patterns in ADH, α-GPD and acid phosphatase compared with other leaf-eating cultivars.
2. Cucumber and melon: Electrophoretic patterns of protein, LDH, esterase, acid phosphatase, SDH and CA were available for separation of cucumber and melon seeds.
3. Carrot, pea and garden bean: No difference of electrophoretic patterns of protein or enzymes was observed among cultivars or groups of cultivars within these respective species.
4. Comparing the possibility of distinguishing species of several genera tested in this report II and former report I, Allium species were most easily detected with electrophoretic method, and Brassica species and Cucumis species were next in order. Comparing the protein method with the enzyme method, the latter is more useful owing to its simplicity of the handling procedures involved. Among enzymes, esterase was most widely available for the detection of many species of seeds.

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The aqueous solution of GA₃, GA₄₊₇, BA or IAA was applied by spraying the ovary of an opening flower on the main stem of cucumber, Cucumis sativus L. cv. Chozitsuochiai No. 2, which was grown in the greenhouse in autumn and winter. GA₄₊₇ and BA were found to be highly active in promoting the fruit setting and development. GA₃ was less active and IAA was not active. The fresh fruit treated with GA₃, GA₄₊₇ or BA at 100ppm was three, ten and five times greater in weight than the control, respectively. The promotion of GA₄₊₇ or BA on fruit growth was obtained by treatment of the ovary at different stages of flower development.

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Studies of in vitro tissue culture were carried out to make a comparison of the responses in adventitious bulblet formation between tissues excised from different parts of parent bulbs. The culture medium used was White′s supplemented with 2% sucrose and 0.8% agar. No exogenous growth regulators were supplemented. All cultures were maintained at 25°C under dark. A preliminary test showed that 25°C and 30°C were best for the culture, and that illumination was not necessarily required for bulblet formation itself, though it hastened the growth of the bulblets formed. The test also demonstrated that the cultures showed no seasonal response with respect to regeneration.
1. Longitudinal position on a scale. Segments containing both tissues of scale base and basal plate produced bulblets from the proximal end of the scale and roots from the basal plate tissue at a high rate. Segments of the extreme base of scale also produced bulblets and the bulblets rooted later. In these cases, a higher regenerative rate was found for outer scale segments than for inner ones. Segments whose proximal end had been located 2mm above the junction of the basal plate produced bulblets at the rate of only 3% and no regeneration was found from those 3mm and more above the junction. Explants of bulb plate tissue alone regenerated neither roots nor bulblets.
2. Position around a scale base. For all circular scales (leaf bases), the leaf-blade-extended-side is thicker than the opposite side. As successive leaf blades extend 180° apart around a bulb, the thicker part of a scale and the thinner part of the next scale are arranged alternately. In the culture of segments of a single scale base, either with or without basal plate tissue, no difference in regenerative rate was shown between those excised from the thicker and thinner parts of a scale. In segments, each containing two thin and thick scale base fragments attached to basal plate tissue, bulblets developed at a higher rate and more rapidly from the position between the scale fragments than from either of the scale surface exposed sides. In a comparison of the two scale fragments with respect to regeneration from the surface exposed sides, the thinner one showed a clear tendency to produce bulblets at a higher rate than the thicker one. Lower regenerative ability of the thicker part, which was not clarified by the culture of a single fragment, appeared to be due to competition of the two segments.
3. Dorsiventral polarity of regeneration. Although some explants with basal plate tissue planted with the adaxial surface upwards regenerated bulblets from the adaxial side of the scale base, most explants regenerated bulblets from basal abaxial areas alone, regardless of the orientation of segments When segments of a scale base with basal plate tissue were bisected parallel to their two surfaces and cultured, more than 60% of the adaxial halves which were planted erectly or with the adaxial surface upwards regenerated bulblets at their proximal end. When segments having both surfaces were cultured in a liquid medium by a reciprocating and a rotary shaker, 17% and 10% of the segments, respectivly, produced bulblets on the adaxial side. These results suggest that some substance involved in the regenerative response and transmittable across the tissue may be more richly concentrated in the abaxial side than the adaxial side of the scal base.

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In order to study the chemical properties of clay pots, constant-boiling hydrochloric acid-, water- and ammonium acetic acid extractable minerals were determined.
1. Among the minerals extracted by constant-boiling hydrochloric acid, Al₂O₃ and Fe₂O₃ were comparatively high, whereas SiO₂ was very low in each sample notwithstanding its high contents in the raw material. Two samples of Tokyo (A and B) had the highest contents in each extractable mineral, but that of Kitaibaraki (D), the lowest.
2. Water-extractable K₂O, Na₂O, CaO and MgO were relatively high, whereas the other elements such as SiO₂, Al₂O₃, Fe₂O₃ and P₂O₅ were very low. Two samples of Tokyo (A and B) had the highest quantity of each water-extractable mineral, while samples of Kitaibaraki (D) and three districts of Aichi pref. (E, F and G) had much less in water-extractable CaO and MgO. Increased extraction of these minerals was found with the increment of water ratio to pot materials from 2: 1 to 20: 1, especially between 10:1 and 20:1.
After the first extraction by water at the ratio of 10:1, the second extraction was done at the same ratio. These secondary water-extractable minerals were considerably less than the first one except P₂O₅. Contents of K₂O and Na₂O dropped to about 60-20% of the first extract, while those of CaO and MgO decreased more remarkably.
3. The contents of NH₄OAc-extractable K₂O, CaO and MgO were more than those of water-extractable ones, except Na₂O. These exchangeable cations of samples of Tokyo (A and B) were considerably higher than those of the other districts, as in the case of the constant-boiling hydrochloric acid- and the water-extractable ones.
4. The results obtained in this experiment suggest that minerals which can be absorbed by plant roots are K₂O, Na₂O, CaO and MgO, but the extractable quantities of these minerals from clay pots seem to vary considerably with chemical compositions of raw materials the firing temperatures and so on.

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1) The embryo culture technique was applied to the immature hybrid embryos for the purpose of enhancing their growth. The embryos used as materials were from 2 crosses between distantly related species or hybrids: L. longiflorum X L. 'Sugehime'and L.'Shikayama'X L. henryi.
2) The Murashige & Skoog medium was recognized as the most suitable among the three basic media for the culture of immature embryos when it was adjusted at pH 5.0 and supplemented with 20-40g/l sucrose. Higher sucrose concentrations than the above mentioned generally enhanced root growth and inhibited shoot growth.
3) The addition of 10^-4-10^-2mg/l NAA to the basic media was effective for the direct germination of immature embryos and the addition of BA tended to lead them to calluses in some degree. Higher NAA concentrations than the above mentioned promoted root growth and inhibited normal shoot growth, while the higher BA concentrations sometimes gave the reverse result to NAA.

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To study the role of photosynthesis in rooting of the cuttings during propagation, changes in the rate of apparent photosynthesis after planting were investigated in relation to some other factors. Five plants, viz. Camellia japonica L., Camellia sasanqua Thunb., Viburnum awabuki K. Koch, Forsythia suspensa Vahl. and Chrysanthemum morifolium Ramat. were used for these experiments. The rate of apparent photosynthesis was determined by measuring the quantity of CO₂ using an infrared gas analyzer.
1. Time courses of the rate of apparent photosynthesis after planting for the above five plants showed a similar tendency, i. e. the rate declined temporarily immediately after planting. However, the extent was much grater in Forsythia suspensa Vahl. and Chrysanthemum morifolium Ramat. which are easy to root.
2. The effect of light intensity on the rate of apparent photosynthesis was investigated at different stages of propagation with the cuttings of Camellia japonica L., Forsythia suspensa Vahl. and Chrysanthemum morifolium Ramat. In general, the rate was greatly stimulated as the intensity was increased to reach a maximum at about 20 klux, and after that it began to decline.
3. To clarify the relationship between the change in the rate and the number of leaves per cuttings, the rates were measured periodically at various stages of propagation with the respective cuttings of Camellia sasanqua Thunb. having one, two and three leaves and those of Viburnum awabuki K. Koch having one, two and four leaves. Almost on difference in the rate was found among those cuttings at the time of starting, while a remarkable decline occured after planting in 3- and 4-leaf cuttings rather than in 1- and 2-leaf cuttings. When compared on the basis of a whole cutting, the rates showed a proportional relation of the number of leaves. A marked decline was also recognized in 3- and 4- leaf cuttings.
4. Canges in water content in the leaves of the cuttings of the five plants showed a similar tendency to those of apparent photosynthesis. The chlorophyll content in the leaves of the cuttings of Camellia japonica L. continued to decrease gradually during propagation.

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Citric acid metabolism in Satsuma mandarin fruit was investigated during storage for 90 days after harvest by injecting with citric acid-1, 5-¹⁴C into the fruit segment. The cumulative radioactivity of respired ¹⁴CO₂ continued to increase after injection with the substrate and the curve nearly leveled off after 10 days. The substrate was metabolized rapidly to cationic and neutral fractions and proteins in both peel and segment of the fruit. The content of titratable acid in the peel and pulp of the fruit continued to decrease gradually during storage. The specific activity of citric acid in the pulp, therefore, decreased to one tenth within 10 days after injection, and retained a constant specific activity for the subsequent 50 days. It is concluded that the rate of turnover of citric acid in the fruit may be considerably high during storage period.

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