Effects of flowering time within a tree of 20-yr-old Kawano-natsudaidai on fruit growth and acid content in the juice were examined. The numbers of fruits per tree were 308 in 1976, and 451 in 1977. Fruit size and acid content in the juice were measured in the following February of each growing season. 1) Set percentage of the fruits earlier in blooming time was low, whereas that of the fruits later in blooming time was conversely high. The number of leaves per bearing shoot was greater in the fruits later in blooming time and the percentage of leafy fruit was also higher in a group of fruits later in blooming time. 2) Fruit growth was greater in the fruits earlier in blooming time and average fruit diameters on December 6, 1976 were 100, 98, 95 and 92mm in the fruits blooming on May 13, 18, 24 and 29, respectively. Percentages of larger fruits above L size were 26.6% in 1976, and 10.2% in 1977, and the average fruit weights were 323g and 301g. respectively. Fruit weight was greater in the fruits earlier in blooming, time and the differences of average weight were 75g between the fruits blooming on May 13 and 29 in 1976, and 69g between the fruits blooming on May 6 and 23 in 1977. Fruit weight was greater in the fruits borne at the upper position of the tree, whereas it was extremely small in the fruits at the lower position, especially, inner part of the same position of the tree. Maximum differences between them were 106g in 1976 and 63 g in 1977. 3) Variation of acid content in the juice ranged from 1.6 to 2.9% in 1976, and from 1.8 to 3.2% in 1977. Their average acid contents were 2.13 and 2.39%, respectively. Acid content in the juice decreased as the number of leaves per bearing shoot increased, and was greatly influenced by the position where the fruits were attached, but hardly influenced by blooming time.
The grape berries accumulate sugar very rapidly around 4 weeks before ripening. In order to clarify the mechanism of this sugar accumulation in Delaware grape berries during Stage III, changes in sugar and organic acid content in the growing berries, effects of the number of leaves retained on and time of complete removal of leaves from a bearing shoot on sugar content in the berries, changes in sugar content in the berries detached from the shoot at Stage III, and the conversion of polysaccharides or organic acids into reducing sugars in the berries were investigated. (1) The major sugars in the grape berries were glucose and fructose. These sugars contained totally about 2% in the fresh immature berries, wheras they were about 17% in the mature berries. The ratio of glucose to fructose in the berries changed during the period from bloom to maturity. Glucose in the berries was more predominantly accumulated than fructose during the green color and the early ripening stage of their growth. This relation was reversed at the later ripening stages. (2) As in most fruits, malic acid is present in grape berries. In contrast to them, however, a large amount of tartaric acid contains in the berries, which is the characteristic of this genus. The concentrations of malic acid and tartaric acid in the berries were highest in the beginning of Stage III and the amount of both acids in the berries decreased markedly during the ripening stage, but another peak of tartaric acid concentration was found in the beginning of Stage I. (3) There were no differences in sugar content of the berries on the shoot with 8 leaves or more, as compared to that of the berries on the control shoot, but the berries on the shoot less than 8 leaves had less sugar content. Even the berries on the shoot completely defoliated still accumulated about 6% of reducing sugars. (4) During Stage III, the accumulation of reducing sugars in the berries was found even after complete removal of leaves from the shoot together with girdling at both sides of the node where the cluster was attached. (5) When the enzymes extracted from the berries during Stage III were added into the insoluble substrate prepared from the berries during Stage I, reducing sugar content in the incubation buffer solution increased. (6) When 14C-malic acid was fed into the berries of Stage III through the pedicel for 2 hours in a liquid form, 31% of incorporated 14C was found in the sugar fraction. From these results, it was cleared that the translocation of photosynthates synthesized in the leaves into the berries was most important for the rapid sugar accumulation in grape berries, and also, the translocation of sugars converted from polysaccharides in shoots into the berries and the conversion of polysaccharides and organic acids in the berries themselves into reducing sugars were found to be related to the accumulation as well.
1. Rooting and shoot growth of hardwood cuttings of grapevines (cv. Delaware) in relation to temperature and their initial weight of 3, 5 and 7g were observed in the growth chambers controlled at 15°, 20° and 25°C in 1974, and 25°, 30° and 35°C in 1977, respectively. 2. Both rooting percentage and root numbers per cutting observed 42 days after planting were highest grown under 25°C regardless of the initial weight of the cuttings, and inferior at higher or lower temperatures. Under each temperature those were greater as the initial weight of the cuttings increased except for 5g-cuttings under 20°C and 3g-cuttings under 15°C being best among the three different sizes. 3. When the final observations were made 70 days after planting, such higher temperatures as 30° and 35°C reduced rooting percentage, especially in 3g-cuttings. The number of roots per cutting was greater with increasing the initial weight of the cuttings regardless of the temperature, 5g- and 7g-cuttings being best under 20°C and 3g-cuttings under 25°C. 4. Dry weight of the cuttings including new shoots and roots at the final obser vation stage was heavier as their initial weight increased. When compared among temperatures, it was best for 7g-cuttings under 25° or 30°C and for 3g- and 5g-cuttings under 25°C, respectively. 5. The carbohydrate contents in the cuttings at the final observation stage were highest under 25°C, being greater with increasing their initial weight. On the contrary, the nitrogen contents were lowest under 25°C, being lower with increasing their initial weight. 6. In conclusion, the heavier the initial weight of the cuttings within the range from 3 to 7g, the better the shoot and root growth regardless of the temperature, though the temperature did not exert equally on all the cuttings which were different in initial weight.
The role of roots on the head formation posture in cabbage was studied by root pruning carried out at various growth stages and in different degrees before head formation. 1. Root pruning affected both the nastic movement of leaves and the leaf shape index (length/width), but did not affect leaf area in plants sown on Nov. 27. Namely, the ratio of length to width was lowered and the leaf hyponasty and rolling of inner leaves were promoted. 2. The roots of cabbage plants, sown on April 14, were pruned on May 22, June 1 and 11 to about halves, and also the roots of the other plants were pruned to 1/4, 2/4, and 3/4 respectively on June 1. It was shown that the head formation posture was not hastened by both early and mild root pruning as compared with the control plants, although the temporary lowering of leaf shape index and promotion of leaf hyponasty in young leaves were found. However, it was remarkably promoted by both later and more severe root pruning. 3. The role of roots on the head formation posture was discussed on the basis of hormone balance.
In order to ascertain whether the growth response to K application could be accurately predicted or not with the exchangeable K content of the soil regardless of conditions, pot experiments with factorial design were carried out on three soils containing different exchangeable K. The original volcanic ash soil containing 91ppm exchangeable K (shown in Table 1) was mixed with a proper amount of K2SO4 and was left for several weeks. These soils contained 240ppm and 442ppm exchangeable K. Radishes (var. Ooakamaru) were grown in 1/2000-are Wagner pots filled with 11kg field moist soils (equivalent to about 6.5kg oven dried soils) containing 91ppm, 240ppm and 442ppm exchangeable K, respectively. Factors combined with K were the light intensity, the soil water regimes, the amount of N, P, lime, Mg and Na. (The levels of these factors were shown in Table 2. ) K treatment was consisted of 2 levels, 0g and 5g K2SO4 per pot. All pots received 2.1g N as ammonium sulfate and 8g P2O5 as superphosphate as the basal dressing except in the N or P experiment. On the soil containing 91ppm exchangeable K, significant increases in the weight of the fleshy root due to K application were obtained in all experiments, regardless of variables of factors combined with K. On the soil containing 442ppm exchangeable K, K application did not increase the weight of the fleshy root in all experiments. On the soil containing 240ppm exchangeable K, significant increases in the weight of the fleshy root due to K application were obtained only in the experiments where the levels of Mg and the soil water regimes were altered, but not in the experiments where the levels of N (calcium nitrate), P, lime, Na and the light intensity were altered. In the N (ammonium sulfate) experiment, K application did not increase the weight of the fleshy root when 2.1g N was supplied, but it increased significantly the weight of the fleshy root when 8.4g N was supplied. In the experiments where significant increases in the weight of the fleshy root due to K application were obtained on the soil containing 240ppm exchangeable K, K concentration of the youngest expanding leaves, the largest leaves and the fleshy roots in radishes grown without K fertilizer was below ca. 3.4%, 3.0% and 6.0%, respectively. Significant and non-significant increases in the top weight due to K application were obtained on the soil containing 91ppm exchangeable K, but this variability in growth responses to K application could not be explained by the levels of K concentration in radishes grown without K fertilizer.
The process of leaf development of chinese cabbage was observed morphologically and histogenetically to clarify the mechanism of head formation. 1) Seedlings of chinese cabbage (cultivar; Nozaki-Kohai No.3) were used in this study and were grown in a phytotron at temperatures of 23°C during the day and 18°C during the night. For histological observations slides were prepared from different parts of the leaves collected at different growth stages of the seedlings by paraffin microtechnique. 2) The leaf shape changed with node positions. The ratio of length to width of the leaf decreased and the number of vascular strands in the midrib increased as node position number inrreased, counting from the basal point. 3) The leaf consists of two distinct parts; lamina and midrib. Midrib includes several parallel veins (with one or several vascular bundles) in the parenchyma massive on the adaxial side. Each vascular bundle is composed of cambium, xylem, phloem and some supporting tissues. Epidermis of midrib consists of one layer of cells. 4) Trichome, an outgrowth of an epidermal cell, is an unicellular hair situated over the veins. The initial cell of the trichome has dense cytoplasm, a larger nucleus and a larger nucleolus as compared with those of other epidermal cells. 5) The epidermis of lamina consists of one layer of cells. Palisade and spongy parenchymatous cells contain abundant chloroplasts. Stomata are differentiated from an epidermal cell of lamina, and distributed at random. The type of stoma complex is anisocytic, having three subsidiary cells surrounding the stoma. The lamina has fine-netted venation. Parenchymatous cells surrounding the thick vein run parallel with the axis. These parenchymatous cells appeared white in the absence of chlorophyll, similar to those in the midrib. 6) During the early stage of development the successive plastochrones in the shoot apex shortened from 1.3 to 0.5 days. In the leaf primordium, the procambium differentiates at the tip of the leaf buttress. With the development of the primordium, the procambium extends into the apical and marginal parts of the leaf before the initiation of vascular bundle differentiation. The interfascicular cambium was observed up to the 11th or the 13th leaf primordium. After the initiation of midrib-like tissue in the leaf primordium, the marginal meristem starts to differentiate leaf lamina, which continues to develop prominently until the attainment of full size. 7) The direction of leaf outgrowth changed with ages. At the lower nodes leaf primordia grew upright, whereas at the higher nodes they folded the shoot apex inward, forming “small head.” 8) A tiny projection composed of larger cells is present between two leaf primordia. It is about 0.5mm long and 1mm wide. Each cell has a large nucleus and nucleolus, having denser cytoplasm as compared with other meristematic cells.
Tomatoes, peppers, eggplants and strawberries were grown in soils fumigated e (MBr) to determine the effect of MBr on the growth and yield, bromine (Br) content in the plants and the content of water soluble Br in the soils. The growth and yield of 4 tesded crops were not affected by MBr fumigation. Br content in the plant parts of 4 crops tended to increase with increasing amounts of MBr. On a dry matter basis Br content in the fruit of 3 crops at 0, 100, 200 and 400g/m3 MBr treatments was as follows: in tomatoes 99, 113, 129 and 186ppm; in peppers 77, 104, 181 and 282ppm; in eggplants 72, 124, 213 and 364 ppm, respectively. Br content in the fruit of strawberries at 0, 200, 400 and 800 g/m3 MBr treatments was 154, 179, 210 and 285ppm, respectively. Water soluble Br in soil just after fumigation was significantly increased with increasing amounts of MBr. It was markedly decreased one and a half months after MBr fumigation at 200, 400 and 800g/m3, and thereafter gradually decreased with time at 400 and 800g/m3.
In the previous paper (6) it was reported that when hypocotyl segments of lettuce seedlings were precultured for a week on the medium including 2, 4-D and kinetin (KIN), adventitious buds were formed successfully in the hypocotyl segments. The present paper deals with the effects of various concentrations of 2, 4-D and KIN added to the White's basal medium singly and in combination on the formation of adventitious buds. The previously defined terms, i.e., ‘initial’ media and ‘transfer’ media, are conveniently used also in this paper. The results obtained are as follows: 1) For the induction of adventitious buds, favorable concentrations of 2, 4-D and KIN added to the initial medium were estimated to be 0.1 to 1.0mg/l and 0.5 to 5.0mg/l, respectively. 2) For the bud formation, it seemed requisite to supply both 2, 4-D and KIN during the entire course of preculture. In fact, if 2, 4-D was singly added to the initial medium during the first 4 days of the preculture, the formation of adventitious buds was completely inhibited even up to the completion of subsequent subculture. This inhibitory effect caused by 2, 4-D, however, was alleviated by subjecting the cultures to continuous illumination. When 2, 4-D was added to the initial medium during the first 2 days of the preculture, its inhibitory effect was alleviated also by extension of the subsequent subculture period, about 10 days, along with the use of culture media supplemented with both 2, 4-D and KIN. 3) By subculturing on the transfer medium supplemented singly with 0.05 to 0.5mg/l KIN, sufficient numbers of adventitious buds were formed, though addition of 2, 4-D to the transfer medium exerted some inhibitory effects on the bud formation in every combination with different KIN concentrations. 4) KIN exhibited the most pronounced inductive effect on the formation of adventitious buds by its supplementation during the period from the first to the second week of the subsequent subculture. 5) From the results obtained, it is suggested that the processes of the adventitious bud formation in the lettuce hypocotyl segments cultured in vitro consist of three distinctive phases, i.e., (1) bud induction that is brought about when precultured for a week on the initial medium including both 2, 4-D and KIN, (2) bud initiation that occurs during the transition period prior to shifting the cultures to the transfer medium containing KIN alone, and (3) bud development that has been completed on the transfer medium.
In the previous paper (10), it was assumed that the induction of adventitious buds in the lettuce hypocotyl segments cultured in vitro was stimulated in the presence of 2, 4-D and kinetin added to the initial medium. In the present investigation, effects of growth factors added to the initial medium on the induction of adventitious bud primordia were compared among the auxins, cytokinins, and cytokinin-ribosides used. The results obtained are as follows: 1) Maximum bud formation was achieved by the addition of 2, 4-D to the initial medium at concentrations from 0.01 to 0.1mg/l, whereas IAA, β-indolebutylic acid (IBA), and NAA did not show any stimulative effects even within a broad range from 0.05 to 10.0mg/l. 2) Various cytokinins were added each to the initial medium at 0.01mg/l and were in order of stimulative activity of bud induction; zeatin (ZIN)>2-isopentenylaminopurine (2ip)>6-benzylaminopurine (BA)>kinetin (KIN). When they were applied in the dark at a concentration of 0.1mg/l, the activity order was partially altered, i.e., ZIN>BA>2ip>KIN. Under adequate illumination, all of the cytokinins tested produced adventitious buds in all hypocotyl segments cultured. 3) As for the cytokinin-ribosides, all ribose derivatives except zeatin-riboside (ZR) failed to produce adventitious bud primordia when applied at the concentration of 0.01mg/l. The cytokinin-ribosides that produced adventitious buds were in order of their stimulative activity; benzyladenine-riboside (BAR)=ZR>2-isopentenylaminopurine-riboside (2iPR)>kinetin-riboside (KR). KR, in particular, was the least active of all the cytokinin-ribosides tested, and little, if any, induction of adventitious bud primordia was achieved by the application of every concentrations of KR. 4) So far as this experiment is concerned, induction of adventitious buds tended to be stimulated more in the light than in the dark, though both 2iPR and KR seemed almost inactive even under artificial illumination.
Experiments were conducted to determine the effect of diluted sea water on the germination, growth and yield of tomatoes. 1) The germination percentage of tomato seeds decreased even at 100ppm Cl 2 days after the test was started. The germination percentage in 6 days was not significantly different among 0 to 1000ppm Cl. Yet, germination at 2000 and 3000 ppm Cl was 80.5 and 21.5%, respectively, and was significantly lower than among 0 to 1000ppm Cl. 2) Transpiration rate of tomatoes transferred to diluted sea water with Hoagland′s soln decreased with increasing sea water concns. 3) Tomato seedlings were grown in water culture with sea water diluted with Hoagland′s soln for 40 days from the 2 leaf stage. The fresh wt of leaves was greater at 250 and 500ppm Cl than that at 0 and 100ppm Cl. The fruit wt was greatest at 0ppm Cl. One plant died at 6000ppm Cl. The osmotic potential of leaves decreased with increasing sea water concns. 4) Tomatoes were grown in sand culture with sea water diluted with Hoagland′s soln. Chlorosis and necrosis occurred on the lower leaves at 2000ppm Cl. These symptoms were markedly severe at 3000ppm Cl and developed from lower to upper leaves. One plant died during the growing period at 3000ppm Cl. Fresh wt of leaves and fruit yields decreased with increasing sea water concns. The leaf content of Cl and Na increased with increasing sea water concns. 5) Tomatoes were grown in soil culture with sea water diluted with tap water. The marginal necrosis in lower leaves was found at the higher concn of sea water. However, plants did not wither even at 3000ppm Cl. Fresh wt of leaves and fruit yields decreased as sea water concns increased. The content of N, P, K, Na, Mg and Cl in the leaves tended to increase with increasing sea water concns. The content of Cl, exchangeable Na and Mg, and EC value of the soil increased as sea water concns increased.
Effects of low temperature treatments of seeds on curd formation and development were investigated, using several cultivars of cauliflower and broccoli, in temperature-controlled and field conditions. 1. Cauliflower plants, ‘Nozaki-wase’, of the 7th or 8th leaf stage were vernalized. Curds were formed at 15°C and 30 days after the start of growing but not formed at 20°C and 25°C until 48 days. 2. After the germinated seeds were chilled at 0°C in the dark for 30 days, cauliflower plants, ‘Nozaki-wase’ were grown at the constant temperatures of 15°, 20° and 25°C. Curds were formed at 20°C in plants when seeds had been chilled, but not in plants when seeds had not been chilled. Therefore, the germinated seeds could be vernalized with the low temperature treatment. There was no effect of chilling treatment of seeds on curd formation at 15°C, where plants formed curds regardless of chilling of seeds, and at 25°C, where plants did not form curds even with chilling of seeds. 3. Under field conditions, the time of curd formation and maturation of seven cultivars of cauliflower, differing in time of maturation, and one cultivar of broccoli was promoted hardly at all with the low temperature treatment of seeds. 4. As the treatment was lengthened, however, the number of leaves from cotyledon to curd and the stem length at curd maturity decreased in all of the cauliflower cultivars. Those of broccoli also slightly decreased. 5. Curd weight and diameter of the cauliflower were slightly inhibited, as the treatment was lengthened, but those of broccoli were promoted. In broccoli, weight and number of lateral flower heads per plant were also promoted with the longer treatment.
The seedlings of benitade (Polygonum hydropiper L.) are used as the garnish for sliced raw fish of white flesh, due to their purplish red appearance. In connection with their appearance, effects of nitrogen, phosphorus and potassium were studied on the anthocyanin and chlorophyll contents of seedlings grown in pots filled with washed sand. Growth measurements, nitrogen and carbohydrate determinations were also made. Seedlings supplied with deionized water only were the control. 1. Seedlings supplied with sodium nitrate, ammonium nitrate and urea, respectively (2, 5 and 10me/l as N), exhibited greenish tinge on their cotyledons and hypocotyls, and had more growth, higher chlorophyll, and lower anthocyanin contents at each nitrogen level, in comparison with the control seedlings exhibiting purplish red appearance. Nitrate seedlings were affected even at 1me. On the other hand, the seedlings supplied with 2me of ammonium sulfate didn′t show any differences compared with the control, and even at 5-10me effects of ammonium nitrogen were less than those of other forms of nitrogen. However, in another experiment ammonium seedlings at 2me had somewhat more growth, higher chlorophyll, and lower anthocyanin contents than the control. 2. Application of sodium dihydrogenphosphate (0.75, 1.5 and 3me as PO4-P) or potassium sulfate (0.5, 1 and 3me as K) showed no differences in seedling growth, chlorophyll and anthocyanin contents compared with the control. Even in case they were applied with nitrate or ammonium nitrogen, any additive effects to those of nitrogen were not found. 3. Seedlings supplied with 2me of ammonium, nitrate and urea, respectively, had higher total and protein nitrogen contents and lower contents of carbohydrates such as total and reducing sugars and starch, however, the difference from the control was the least in ammonium seedlings. Nitrate seedlings were lower in carbohydrate contents even at 1me. The decrease of anthocyanin in the seedlings supplied with nitrogen was discussed with relation to the decrease of carbohydrate contents due to the increment of nitrogen fractions.
In the present work, effects of 2, 4-D and kinetin of various concentrations in the medium on adventitious bud formation and its subsequent development in the excised scale of tulip was studied in relation to the morphogenic potential of differently aged bulbs. The concentration and combination of 2, 4-D and kinetin with other ingredients in the culture media were modified to find out effective compositions of media that bring about the differentiation of adventitious buds. When excised scales of bulb, cv. ′Apeldoorn′, were cultured on Murashige-Skoog′s medium, the most suitable combination of auxin combined with kinetin was 1.0-1.4mg/l 2, 4-D for this purpose and that of cytokinin combined with 2, 4-D was about 3mg/l kinetin. The initiation of adventitious buds in the scales cultured in vitro was greatly affected by the age of mother bulbs. The cultures failed to initiate bud formation unless cultured explants were taken from the suitably aged bulbs, even when the other conditions were favorable to it. August for ′Apeldoorn′ and May for T. hageri were the most suitable time for sampling each bulb scale culture. Lower concentration of growth substances in the medium were more effective to the subsequent development of newly formed buds when cultured in the light for additional 3 months. As a result, small bulbs were formed eventually at the base of the adventitious bud.
Green soybeans, a common crop in Japan, is harvested at the green-pod stage and its somewhat immature seeds are eaten as a snack etc. The taste of the seeds, however, deteriorates much more rapidly than the visual quality. This paper reports the investigation on the factors concerning the post-harvest quality deterioration and the means of keeping quality, especially applicable under non-refrigerated conditions for practical use. Shirayama-and Komagi-dadachamame cultivars were used and their pods were packaged in perforated polyethylene (PE) bags and held at 0°, 5° and 20°C, respectively. Organoleptic test showed that the taste of soybean became flat in 2 days at 20°C. Yellowing or browning of pods began after several days at 20°C, and 2 weeks at 5 °C. At 0°C, the loss of freshness of pods was noticed after about a month, while green color remained. Sugar content, index of free amino acid content (ninhydrin-positive substances), and L-ascorbic acid content in seeds drastically decreased in 2 days at 20°C. At 5 °C, marked decrease in sugar and amino acid was found after a week. At 0°C, amino acid considerably decreased after 2 weeks of storage while sugar content showed little change. Post-harvest deterioration in the taste of the green soybeans is supposed to be principally attributable to the decrease of sugar and amino acid. When metabolic inhibitors were applied to the seeds by vacuum infiltration, change of the sugar content was retarded with NaF and 2, 4-dinitrophenol (DNP), and that of amino acid with cycloheximide and DNP. Some other pods were packed in PE bags of 0.07mm film-thickness, and the atmosphere in bags was replaced by N2or CO2, or withdrawn under vacuum. These treatments brought about a retardation of sugar loss, and an increase of amino acid in contrast with a sharp decrease in non-treated pods. Simple sealing also had a comparable effect to the a bove-mentioned treatments, showing high CO2 and low O2 concentrations in the bag during the days succeeding the sealing. At 20°C, however, shelf life reduced to 3-4 days since a symptom of gas injury developed on the surface of pod and seed. At 5°C, no injury was found during 2 weeks of storage and loss of sugar and amino acid was considerably retarded. Packaging of a whole plant with leaves and pods attached in a PE bag of 0.03mm-thickness exhibited a marked effect on keeping quality, and preferable taste was kept for several days even at 20°C. External appearance was also maintained by this means, and pod color remained green without any gas injury for more than 10 days at 20°C.