One-year-old satsuma mandarin (Citrus unshiu Marc. cv. Okitsu Wase) trees on trifoliate orange rootstocks were grown in growth chambers with constant temperatures of 15, 20, 25 and 30°C and under field conditions for 6 or 8 months. The effects of temperature on root elongation, root hair development, physiological activity and free proline accumulation in the fibrous roots were investigated.
Root growth was greatly restricted at 15°C. At 30°C roots grew most vigorously, and were the longest and the heaviest. They also developed finer fibrous roots and more root hairs than at all other treatments. Length of the root hairs increased with rising temperature. The most common type of root hairs was papillate at 15°C and cylindrical in the other treatments. TTC reducing activity of the fibrous roots of trees at warm temperature (above 20°C and in the field) rapidly increased from April to June, and then decreased. However, the activity at 15°C was constant from April to June, and slightly increased from June to December. Free proline accumulated more in fibrous roots at 15°C than in other treatments. Fibrous roots of trees grown in the field accumulated much proline in December.

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One-year-old satsuma mandarin (Citrus unshiu Marc. cv. Okitsu Wase) trees budded onto trifoliate orange rootstocks were subjected to different soil temperature (15, 20, 25 and 30°C) and air temperature treatments (25°C in Experiment I, and 15 and 30°C in Experiment II) for 6 or 7 months. The effects of air and soil temperatures on vegetative growth and flower bud differentiation were investigated.
The number of flushes and total length of the shoots increased with rising soil temperatures. When soil temperatures were above 20°C, the number of flushes at an air temperature of 15°C was less than at 30°C. The length of spring shoots at an air temperature of 15°C was longer than at 30°C. However, due to the trees at air temperature of 30°C having more growth cycle flushes, the total length of the shoots did not differ among treatments. The dry weight of the trees increased with increases in both air and soil temperatures. Both low air and low soil temperatures affected flower induction greatly. At an air temperature of 30°C, flower buds developed only at soil temperatures of 15 and 30°C. At an air temperature of 15°C, flower buds developed even when the soil, temperature was 30°C. Trees with air/soil temperatures of 25/30, 30/25 and 30/30°C did not bear any flower buds. The effects of temperature on mineral nutrient content were slight. The roles of soil and air temperature on vegetative growth and flower formation are briefly discussed.

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The embryogenic callus of ‘Valencia’ orange, ‘Yoshida’ navel orange (Citrus sinensis (L.) Osbeck), Calamondin (C. madurensis Lour.), Yuzu (C. junos Sieb. ex Tan.) and ‘Ishizuka Wase’ satsuma (C. unshiu Marc.) were exposed to 1, 5, 10, 20 and 50 kiloroentgen (kR) of gamma irradiation at the dosage of 1kR/h in Institute of Radiation Breeding, Ministry of Agriculture, Forestry and Fishery, Japan.
The irradiation caused a retardation of callus growth. Callus growth was reduced to 500 or less of that in non-irradiated callus, at a dosage of 5kR in Yuzu, 20kR in ‘Valencia’ orange and ‘Ishizuka Wase’ satsuma, and 50kR in ‘Yoshida’ navel orange and Calamondin.
The irradiation stimulated embryoid formation from the callus. Optimum irradiation dosages to produce the maximum number of embryoids were 50kR in ‘Valencia’ orange, 20kR in Yuzu, 10kR in Calamondin and ‘Ishizuka Wase’ satsuma. ‘Yoshida’ navel orange produced the maximum number of embryoids at the lowest irradiation of 5kR.
The ratios of embryoid number produced at the optimum irradiation to that at non- irradiation were, 16.4, 8.4, 7.8, 6.4 and 2.7 in Yuzu, ‘Ishizuka Wase’ satsuma, ‘Valencia’ orange, ‘Yoshida’ navel orange and Calamondin, respectively.

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The tissues affected by the necrotic disorder of berries in ‘Muscat of Alexandria’ grape were examined under light and fluorescence microscopes and scanning electron microscope to determine the causal factors.
As reported previously, the disorder is classified into two types according to its symptoms, “Speck” and “Shrink”; “Shrink” can be further classified into two types, “Real Shrink” and “Scald”.
The occurrence of “Speck” is limited to the vicinity of peripheral vascular bundles. In the affected berries, small cavities which seem to have developed as a result of destruction of parenchyma cells were observed around the vascular bundles, and part of the cavities were filled with newly formed cells.
Intensive fluorescent spots were observed through fluorescence microscopy at some of the phloem cells in the browned bundles adjacent to “Speck” symptom. Starch grains were occasionally observed around the destroyed parenchyma tissues. These phenomena were also observed in the berries of other cultivars such as ‘Pizzutero Bianco’, ‘Kyoho’ and ‘Campbell Early’ but not in ‘Muscat Bailey A’ in which “Speck” rarely appears.
The initial symptom of “Shrink” appears on the shoulder of a berry. In “Real Shrink” berries, necrotic cavities were observed in the pericarp just beneath the skin, which were larger in size than those observed in “Speck” berries. The affected portions of these berries were obviously hollow. The symptom of “Scald” developed more rapidly over the whole berry than did that of “Real Shink”, when the cavity was not observed.
In “Shrink” berries, the vascular bundles at the basal portion partially or sometimes completely turned brown in color. The same phenomenon was observed in the vascular bundles of their receptacles or occasionally in those of their pedicels. In “Real Shrink” berries, vascular bundles of the affected side alone showed such changes in color. In “Scald” berries, in which the browning was usually observed at the whole basal portion of the central vascular bundles, the eosin Y solution did not permeate beyond that portion, even if the solution was injected from the cut end of the rachis under a certain pressure. When it was injected in the same manner into a cluster composed of three types of berries in terms of necrotic disorder (49%; healthy, 34%; “Speck” and 17%; “Shrink”), the percentages of berries in which the dye was detected in all the bundles at the basal portions were 75% in the healthy berries, 43% in the “Speck” ones and 0% in the “Shrink” ones.
In some browned bundles, the xylem vessels were stuffed with tylose-like substances. When part of the basal portion of the berry or part of the receptacle of a cluster on a vine was cut with razor blades made of stainless steel, or when the vascular bundles were blocked with fusaric acid, which is known as a tylose gel-inducing substance, there occurred no such symptoms as those of the necrotic disorder. However, when they were cut with steel blades at the Stage II of berry development, injuries similar to the disorder were observed. Therefore, the necrotic disorder of grape berries does not seem to occur due to a mere blocking of some bundles, but due to some unknown toxic effects.

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We carried out a comparative test with mixed planting in the same field using virus-free and virus-infected (leafroll and fleck) vines of red wine-grape cultivars, ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ (Vitis vinifera L.). Although initially virus-free vines were 7 or 8 years old, they have been reinfected.
In this paper, seasonal changes in °Brix and titratable acidity of grape juice were investigated over a 3 year period (1985 to 1987, tree age: 6 to 8 years), and we detected and identified the viruses of these cultivars.
The results are as follows;
1. At full maturity, the °Brix values of the juices of virus-free ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ were higher than those of virus-infected vines, in 1985 (6-year-old vines). However, in 1987 (8-year-old vines), the °Brix values of the virus-free varieties were lower than those of virus-infected vines.
2. Titratable acidities of the juices of virus-free ‘Cabernet Sauvagnon’ and ‘Cabernet Franc’ were lower than those of virus-infected vines at full maturity in 1985. However, in 1987, titratable acidities of virus-free ‘Cabernet Sauvignon’ and ‘Cabernet Franc’ were higher than those of virus-infected vines.
3. We found that the initially virus-free vines were reinfected by leafroll and fleck viruses. We think that in 1987, the infection by leafroll and fleck viruses caused the decrease in °Brix and the increase in acidity of juices, as well as light-colored fruits and red leaves in these initially virus-free vines.

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Investigations were carried out to clarify the effects of root temperature on carbohydrate contents in potted or benched ‘Muscat of Alexandria’ vines grafted on ‘Hybrid Franc’ rootstock. Root temperature was controlled to 13°C and 27°C from December nd from February, under forcing conditions. Seasonal changes in carbohydrate contents in unheated vines were also determined for comparison.
1. In vines heated from both December and February, the higher the root temperature, the fewer days to budbreak, the higher the budbreak percentage, and the more vigorous the shoot growth, especially in forcing from December. When forced from December, development of flower clusters was more vigorous at 27°C than at 13°C, while there was little difference between the two temperatures from February forcing.
2. In unheated vines, starch content decreased toward bursting stage in all parts, including rootlets (below 2mm in diameter), lateral roots, trunk and cane, especially in the rootlets. However, total sugar content in each part increased up to Junuary or February; after reaching a maximum level, it decreased rapidly toward bursting, especially in canes. When forced from December, total sugar content in canes increased after the start of the treatments at both 13°C and 27°C, and decreased toward bursting, especially at 27°C, where budbreak was promoted. On the other hand, there was a marked decline just after the start of the treatments on total sugar content at either temperature forced from February. Starch content in rootlets decreased markedly toward bursting at 27°C with forcing from both December and February, whereas no notable difference between the two temperatures was observed in canes. The pattern of seasonal changes in trunk and lateral roots corresponded to that in canes and rootlets, respectively.
3. The lowest concentration of total sugar in sap bled from canes was observed at bursting stage in unheated vines, whereas in heated vines it occurred just after the start of the treatments in all plots. Sugar concentration in sap was always lower at 27°C than at 13°C, regardless of time of forcing. When heated from December, content of starch and sugars in shoots was less at 27°C, at which growth of shoots and clusters was vigorous, than at 13°C, but little difference was found between the two temperatures from February.
4. From these results, it was considered that the poor growth of shoots and clusters which occurred at the low root temperature of 13°C in vines heated from December, due to the fact that the seasonal change in carbohydrate nutrients in vines was small throughout the short growing period, and that the utilization of carbohydrates in shoots was also small.

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The major cause of poor sets of normal seeded berries in ‘Pione’ grapes is that most of the pollen tubes are inhibited from growing further at the basal part of the style or the upper part of the ovary. To clarify whether this inhibition is due to self-incompatibility or not, we conducted several pollination tests and heat treatments on prebloom and blooming flower clusters.
1. Reciprocal pollination tests using pollen of ‘Muscat of Alexandria’, ‘Campbell Early’ and ‘Benizuiho’, where a number of pollen tubes grow in their pistils, showed that the number of pollen tubes growing into each part of ‘Pione’ pistils was not greater than in selfed ones. The percentage of set of seeded berries and average seed number were also not increased by cross pollination. Pollen tube growth in those three cultivars, on the other hand, was inhibited to some degree, depending on the cultivar, when crossed by ‘Pione’ pollen.
2. Repeated self pollinations every 6 hours for 2 days did not improve pollen tube growth in ‘Pione’ pistils. Pollinating every 2 hours, however, increased the number of tubes reaching the style and upper and middle parts of an ovary, though their further growth into micropyles was not affected. The set of seeded berries was also not improved by repeated pollinations.
3. Bud pollination (3 days before anthesis or earlier) and delayed pollination (4 days after or later) did not enable pollen tubes to grow into the styles or ovaries of ‘Pione’ pistils. Following pollination one day before or 2 days after anthesis, pollen tubes grow into the pistils as with pollination at anthesis.
4. Heat treatments such as 40, 45, and 50°C for 5, 15, and 30 seconds or 30 minutes on pre-bloom or blooming ‘Pione’ flower clusters did not increase the number of pollen tubes reaching each part of the pistils.
5. From these results, we conclude that the inhibition of pollen tube growth in ‘Pione’ pistils may be caused by some other mechanism than that of self incompatibility.

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The characteristics of removal of astringency of two Japanese persimmon (Diospyros Kaki Thunb.) cultivars, ′Denkuro′ and ′Hiratanenashi′, when treated with warm water, ethanol vapor and CO₂ gas, were investigated.
The patterns of the changes in peel color and flesh firmness were much the same for each treatment in both cultivars.
The astringency of ′Denkuro′ and ′Hiratanenashi′ fruits was removed with both warm water and CO₂ treatments. Decrease of soluble tannin occurred earlier in ′Denkuro′ than in ′Hiratanenashi′ in warm water treatment. In the ethanol treatment, astringency of ′Hiratanenashi′ was removed gradually and thoroughly, whereas there was almost no decrease of soluble tannin in ′Denkuro′ for 6 days.
Ethanol and acetaldehyde accumulated in the flesh earlier and their levels were a little higher in ′Denkuro′ than in ′Hiratanenashi′ fruits when treated with warm water. The patterns of ethanol and acetaldehyde accumulation were almost the same in CO₂ treatment in the two cultivars. In ethanol treatment, much more ethanol accumulated in ′Denkuro′ than in ′Hiratanenashi′ fruits, but only little acetaldehyde was detected in ′Denkuro′, while a small but obvious amount accumulated in ′Hiratanenashi′. The decrease of soluble tannin was, on the whole, closely related to the level of acetaldehyde accumulation in both cultivars.
The responses of fresh juice to acetaldehyde vapor seemed almost the same between the two cultivars.
From these results, the cultivar differences between ′Denkuro′ and ′Hiratanenashi′ and their regulative mechanisms in removing astringency were discussed.

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Promotion of development of cucumber fruit (Cucumis sativus L. cv. Chojitsuochiai No. 2) was achieved by the application of gibberellin A₃ (GA₃) and gibberellin A₄₊₇ (GA₄₊₇) to its flower. The promotive activity of GA₄₊₇ was much greater than that of GA₃. Their activities increased in parallel with higher concentrations. The promotive activities of gibberellin A₄ (GA₄) and gibberellin A₇ (GA₇) were also higher than GA₃.
The level of endogenous gibberellins in the placental tissue and the sarcocarp of parthenocarpic fruits was examined in relation to their development by using thin layer chromatography (TLC) followed by the rice seedling test. Three zones of gibberellin activity were found in the acidic and the nonacidic fraction from each of the fruit tissues. These zones were co-chromatographed on TLC with GA₃, GA₄/GA₇ and gibberellin A₉ (GA₉). Total amounts of three gibberellins in both placental tissue and sarcocarp increased with development of the fruit which fitted with a role for gibberellins in promoting development of cucumber fruit. Existence of larger amounts of the gibberellins in the placental tissue suggests a potential for production of parthenocarpic fruit in this variety of cucumber.

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Respiratory response of detached roots to lower temperatures was compared between a chilling-sensitive species, cucumber (Cucumis sativus L. cv. Suyô) and a less sensitive species, figleaf gourd (Cucurbita ficifolia Bouchè), which were grown at a root temperature of 20°C. Respiration of figleaf gourd roots was less susceptible to low temperature than that of cucumber roots. It was mainly the cytochrome respiration that was responsible for the differential susceptibility of root respiration. Experiments with 2, 4-dinitrophenol(DNP) indicated that the oxidative phosphorylation rate was higher in figleaf gourd than in cucumber roots at low temperature. These results strongly suggest that the response to low temperature of the cytochrome respiration of roots, coupled with oxidative phosphorylation, is an important aspect of differential root-chilling tolerance between cucumber and figleaf gourd.

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A method was developed for the quantitative determination of 4-methylthio-3-butenyl glucosinolate, which is predominantly contained in daikon root, using gas chromatography (GC) after enzymatic conversion to its isothiocyanate. This method is based on the extraction of glucosinolate with ethanol, purification with anion exchange resin, and hydrolysis with crude myrosinase which was prepared from daikon root. The formed 4-methylthio-3-butenyl isothiocyanate was dissolved into methylene chloride, and measured by GC. The coefficient of variance of 5 samples from one daikon root was about 4% through all procedures in this method.

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Eggplants, cv. Hayabusa, Kokuyou and Beikokudaimaru, grown either on their own roots or on the rootstocks, cv. VF, Akanasu and Torubamu, were used to study the effects of rootstock on the yield of eggplant in relation to the number of thick roots, mineral flux and hormone levels in xylem sap.
1. All of three varieties grafted on VF showed the highest yield and the most vigorous growth, and more thick roots were found on those plants. Own-root plants produced lower yields with fewer thick roots than grants. There was a close positive correlation between the number of thick roots and yield.
2. Xylem exudation rate and mineral flux in xylem sap were the highest in the plants grafted on VF. The mineral flux, especially nitrogen, was closely correlated with yield.
3. Cytokinin, gibberellin-like substances and indole-acetic acid levels were the greatest in the xylem sap of plants grafted on VF rootstock, which produced the highest yield. The difference in yield between rootstocks was significantly attributed to difference in cytokinin production, depending on the number of thick roots.
4. From these results, it may be concluded that the growth and yield of eggplant was affected by mineral absorption and hormones especially cytokinin production of rootstocks via many thick roots.

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The contents of capsaicin and its analogues and their constitution were studied, in the fruits of interespecific hybrids of Capsicum annuum and C. chinense. Results obtained are as follows.
Interspecific hybrids were obtained between sweet varieties of C. annuum and C. chinense ‘No. 3341’ which was rarely pungent. Capsaicinoid content was very high in the fruit of the hybrids. Changes in capsaicinoid content during fruit development of the hybrids, were comparable to those of common pungent varieties of C. annuum. Capsaicinoid constitutions in the hybrids were all identical.
Interspecific hybrids were obtained between pungent varieties of C. annuum and C. chinense ‘No. 3341’. Their capsaicinoid contents were higher than, nearly the same as, or lower than the pungent parents.
Capsaicinoid contents were much lower than that of the pungent parents, in the progenies from intraspecific crosses between ‘California Wonder’ and pungent varieties of C. annuum. No capsaicinoid was detected in cases from crosses between ‘California Wonder’ and sweet varieties.

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Maturity of netted muskmelons (Cucumis melo L., var. reticulatus, cvs Earl′s Favourite and Napoleon) is difficult to estimate by their appearance. Ethylene and flavor volatiles production of the melons were found to be good indicators in estimating maturity.
Keeping qualities of the melons during postharvest storage were highly dependent on the fruit′s maturity and on storage methods. Modified atmosphere in seal-packaging with polyethylene bags and ethylene-removing treatment on seal-packaging were effective to maintain qualities of the melons which were at proper maturity stage for harvesting (ethylene production: <0.1μl/kg/h), but were not satisfactory for physiologically more aged melons which were properly matured for eating (ethylene production: >0.3μl/kg/h).
Keeping-quality periods of the melons were 1 week at 20°C, 2 weeks at 10°C or 3-4 weeks at 4°C, and were not prolonged by low pressure storage.

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In order to establish a reasonable culture procedure for edible asparagus (Asparagus officinalis L.) in the warm regions of Japan, it is necessary to determine its physiological and ecological characteristics.
This paper reports on the photosynthesis of asparagus, which plays the basal role for growth, development, and dry matter production for the following season.
1. Photosynthesis in asparagus was mainly observed on cladophylls into which stems turned. The main stem, and lateral shoot to which cladophylls were not attached also photosynthesized. Especially, the net photosynthetic rate of lateral shoots of 0.5-1mm diameter reached about 30% of that of cladophylls measured as mg CO₂ per 1g dry weight per hour. The net photosynthetic rate of main stem was 0-3% of that of cladophylls.
2. Respecting the effect of light intensity on net photosynthesis, net photosynthetic rate of most plants at the early and middle stages, and at the late stage of development was saturated at 40-50klx and 10-20klx of light intensity respectively. Light compensation points of them were ranged from 1.5 to 2klx.
3. Respecting the effect of CO₂ on net photosynthesis, when measured by increasing the CO₂ concentration (400→1400ppm), CO₂ saturation was observed between 400 and 1000ppm. On the other hand, when measured by decreasing the CO₂ concentration (1400→400), CO₂ saturation was not observed in the range from 400 to 1400ppm. The photosynthetic rate measured with the latter procedure was less than that of the former, compared at each of the same CO₂ concentrations.
4. The favorable range of temperature for photosynthesis was 20±5°C.
5. The response to light, CO₂ and temperature for net photosynthesis was similar among plants at early, middle and late stages of development. Diurnal fluctuation of net photosynthesis was clearly observed when intact plants were measured, and the net photosynthetic rate decreased in the afternoon. On the other hand, cut plants did not show this fluctuation.

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Effects of quantity and temperature of storage roots on the elongation rates of spears were studied using 1-year-old asparagus.
1. The elongation rates were affected by the sizes of crowns. The spears from normal-sized crowns grew exponentially, but those from small-sized crowns grew almost linearly.
2. The spears grew exponentially while storage materials were plentiful in storage roots, but grew linearly and then parabolically as the materials were exhausted.
3. The elongation rates of spears were influenced by root temperature. Rates were highest at 20 or 25°C. The more the temperature deviated from these levels, the more the rates decreased. But spears grew exponentially even at aroot temperature of 5°C. It was probable that root temperature affected the elongation growth of spears not directly, but indirectly by modifying the temperature of spear and/or rhizome.
4. The temperature treatments of buds for about 2.5 days before sprouting did not influence the subsequent elongation growth of spears.
5. The ratios of water-weight: dry-weight in spears grown at root temperature of 10°C were lower than those at 15 or 20°C.
It was suggested that as long as available storage materials were plentiful, spear growth was mostly influenced by spear and/or rhizome activities rather than by root activity.

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Changes in carbohydrates of the storage roots of asparagus on sprouting were studied.
1. In the storage roots, fructose, sucrose and fructans were present consistently, but glucose was rarely found. Fructans as storage carbohydrates were identified from 3 to 13 degrees of polimerization.
2. There was a carbohydrate concentration gradient along the storage root 2 days after sprouting. Concentrations of fructose and sucrose increased toward the root apex, but those of fructans decreased.
3. In rhizomes, concentrations of fructose and glucose were almost equal, and the concentration of sucrose was 5 times that of hexose.
4. Before sprouting, concentrations of fructose and sucrose in the storage roots decreased, but those of fructans did not change remarkably by 1 day after sprouting.
5. After sprouting, the concentration of fructose in the storage roots began to increase from 5th day at 20°C and from 8th day at 10°C. The increasing rate was higher at 20°C. Concentrations of sucrose and fructans did not change much.
6. In the detached root segments, no changes were detected in carbohydrate concentrations regardless of temperature.
7. Exogenously applied plant hormones such as GA₃, GA₄ and IAA did not influence carbohydrate concentrations in the detached root segments, regardless of temperature. It was suggested that breakdown of fructans in intact storage roots was not influencedby plant hormones.

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Studies were carried out to elucidate the effects of 4-CPA (4-chlorophenoxy acetic acid) on translocation and distribution of ¹⁴C-assimilates in fruits growth of tomato.
The distribution pattern of ¹⁴C-assimilates from the leaves just above and just below the 1st inflorescence was changed by 4-CPA (15ppm) treatment. The accumulation of ¹⁴C-assimilates to the 1st inflorescence started earlier and increased rapidly. However, the magnitude of the effects to the distribution pattern was different according to the leaf position. The pattern from the leaf just below the 1st inflorescence was extremely affected by 4-CPA but not from the leaf just above the 1st inflorescence, because the role of leaf to 1st inflorescence is different. That is, the sympodial branching system and the degree of connection of vascular bundles affect the distribution pattern. These phenomena were also found in the various leaf positions in other experiments.
From these results, it can be shown that 4-CPA is the activator of the sink or activates the sink earlier. However, it is probable that the increase in accumulation of assimilates to the inflorescence is not a direct effect of 4-CPA, because the effects sometimes do not appear by the fail of timming of 4-CPA treatment.
It seems that the latant ability of the flower itself for development is fully brought out by the activation of the sink or the acceleration of accumulation of assimilates with 4-CPA treatment.

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Glutamate oxaloacetate transaminase (GOT), isocitrate dehydrogenase (IDH), phosphoglucose isomerase (PGI) and phosphoglucomutase (PGM) isozyme banding patterns were investigated in 27 cultivars of Allium wakegi, 3 cultivars of A. ascalonicum (shallot), 7 cultivars of A. fistulosum (Welsh onion or Japanese bunching onion) and 2 cultivars of A. cepa (onion). Although there is distinct morphological and ecological intraspecific differentiation in A. wakegi, almost no zymographic variations were observed among the cultivars except Ginoza′. Our findings that some PGI bands in ′Ginoza′ are seen only in A. fistulosum cultivars and others are common in all A. wakegi cultivars and that some morphological and ecological characters in ′Ginoza′ differ from those in other A. wakegi cultivars (reported previously) suggest that this cultivar may have originated as a backcrossed plant between A. wakegi (A. fistulosum×A. ascalonicum) and A. fistulosum.
A. wakegi is easily separable from A. ascalonicum, A. fistulosum and A. cepa though the discrimination between A. ascalonicum and A. cepa seems to be difficult by the isozyme patterns investigated here, showing the similarity between these two species.

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Seedling emergence of carrot was compared among four presowing seed treatments imbibition, priming, pregermination, and pregermination following priming. Five experiments in pots were carried out in plastic houses in seasons at lower and higher temperatures. The effects of seed treatments were evaluated under different daytime temperatures or under different soil moisture conditions.
Percentage seedling emergence in the seasons at lower temperatures was improved with all tested seed treatments when daytime temperature was lower or soil moisture percentage decreased rapidly. Treatments of priming and/or pregermination following priming gave good results in percentage emergence. In the season at higher temperature, percentage emergence was improved similarly with treatments of priming, pregermination, and pregermination following priming.
The start of emergence was advanced more with priming than with imbibition in both seasons, and more with pregermination following priming than with pregermination under the lower soil moisture conditions in a season at lower temperature. These effects of priming treatment suggested that growth of radicles and/or plumules was promoted during germination and emergence.
Mean emergence time was shortened in all treatments, most remarkably with pregermination following priming, considerably with priming or pregermination, and to some degree with imbibition. Spread of emergence times was not reduced consistently with any presowing seed treatment.
The results indicated that a most effective presowing seed treatment for improving seedling emergence of carrot was pregermination following priming, or priming only, in the seasons at lower or higher temperatures, respectively.

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This study was undertaken to clarify the environmental effects after flower-bud initiation on flower-bud growth and development and on cut-flower quality of forced tree paeony (Paeonia suffruticosa Andr. cv. ‘Hanakisoi’).
1. Flower-bud development at digging (the first 10 days of September) was advanced if late summer temperatures were low. When plants were treated with temperature, the development of flower buds under LT(27°C, 5, 000lx (day)/21°C (night)) treatment was hastened when compared to that under HT(31°C, 5, 000lx (day)/25°C (night)) or C (field) treatments. Cut-flower quality from plants in the LT treatment was superior to that in the other treatments. Under the C treatment, the highest temperature during summer, flower-bud development was delayed, flowering percent was low and cut-flower quality was poor.
2. Although daylength had no influence on flower-bud formation and cut-flower quality, the flowering percent for SD (24°C, short daylength (8 hours, 300lx)) treatment was low compared to the LD(24°C, long daylength (16 hours, 300lx)) treatment.
3. The number of days from emergence to flowering under 18°C forcing condition was about 30 for all treatments and the corresponding cumulative degree-day temperatures were within the range of 510°C to 560°C.

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Comparative studies were made between two carnation cvs. Scania and Coral, on the translocation of photosynthates for 24 hours after feeding ¹⁴CO₂ in day time.
Eight plants of each cultivar in plastic pots were grown in a greenhouse until the flowering period, and then taken into two growth chambers controlled at 10°C (N 10) or 15°C (N 15) in the dark (14 h-day and 10 h-night, 20°C in the day) and kept growing for 40 days from October 1 to November 9.
The selected two plants of each cultivar in each growth chamber, namely 8 plants, were put in an assimilation chamber in an isotope-greenhouse and fed with 200μCi ¹⁴CO₂ for one hour from 1.00 to 2.00 p.m. The plants were taken out immediately (A plot) and 24 hours (B plot) after trapping the residual ¹⁴CO₂ in the chamber with 1N KOH and NaOH solutions for one hour, respectively.
Growth of cv. Scania, namely: stem length, number of leaves and cut flowers, at N 15 was superior to that at N 10. Cv. Coral showed a more significant growth at N 10 than N 15.
In cv. Scania grown at N 10, ¹⁴C-radioactivity was relatively high in leaves attached to both the primary and secondary branches in A plot, and was highly increased in the terminal and lateral buds of the secondary branches in B plot. In those treated at N 15, the activity was significantly high even in A plot, as well as in B plot.
In cv. Coral, irrespective of the thermal treatment, the radioactivity was similarly high in both the terminal and lateral buds on the secondary branches in A plot, with a slight increase in those buds in B plot.
In cv. Scania grown at N 15, the percentage of ¹⁴C-radioactivity of the secondary branches to the total of the whole plant was as high as about 70% for both A and B plots. In cv. Coral at N 10, the percentage was relatively high, being about 60% for A plot and 75% for B plot. In the case of N 15, similar results were obtained.

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The volatile compounds of Camellia flowers were studied. In order to directly analyze the naturally dispersing volatile compounds of fresh flowers, head space analytical techniques were mainly used. The results were as follows.
1. Linalool oxide (pyranoid, franoid), linalool, methyl benzoate, methyl salicylate, phenyl ethyl alcohol, benzaldehyde, benzyl alcohol and acetophenone were found in Camellia flowers.
2. The odors of Camellia flowers were classified into 4 types according to olfactory evaluations and head space analysis.
3. There were some relationships between classification of odor types and taxonomy, and acetophenone was found only in the C. sazanqua group. These resutls indicated that the C. vernalis group was produced by natural hybridization between C. japonica LINN. and C. sazanqua THUNB.

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D-glucose-U-¹⁴C and shikimic acid-G-¹⁴C known as good precursors for biosynthesis of aromatic compounds were fed to the tissue slices of both the apical and the basal sections of bamboo shoots for 3, 6, 9 and 21 hours at 30°C. After incubations, alcohol soluble substances were extracted with 70% methanol and then separated into organic acid, sugar and amino acid fractions by ion-exchange chromatography. The homogentisic acid fraction was collected from organic acid fraction by HPLC. In the meantime, lignin aldehyde was separated from alcohol insoluble residue by the method of alkaline nitrobenzene oxidation. The radioactivity incorporated into each compound was measured using a Packard Tri-Carb Scintillation spectrometer after adding toluene scintillator.
1. Glucose-U-¹⁴C was mainly incorporated into alcohol insoluble residue. The activity increased with the progress of incubation time and after 9 hours of incubation, it reached to 13.6% of the total radioactivity in the apical section and 52.5% in the basal section, but in which the activity of ¹⁴C incorporated into lignin aldehyde was very low. By determining the activity incorporated into each amino acid from glucose, it was found that the radioactivity was detected in almost all of amino acids, and also that the highest activity was found in alanine among amino acids in both sections. In the meantime, the radioactivity incorporated into tyrosine or phenylalanine was several percent in both sections.
2. Shikimic acid-G-¹⁴C was steadily incorporated into the tissues during incubation and was rapidly converted to aromatic amino acids (tyrosine and phenylalanine). The incorporation of shikimic acid into lignin aldehyde increased during incubation and the activity was higher in the basal section than in the apical section. On determining the amount of homogentisic acid, it was found that the change from shikimic acid to homogentisic acid was very low in both sections.

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An automated system was developed for measurement of the rates of O₂ uptake, CO₂ output, and C₂H₄ evolution by fruit and vegetables simultaneously by use of a microcomputer and three gas chromatographs. The microcomputer was also used to regulate sample temperature and prepare the gas mixtures of ₂2, CO₂, N₂, and C₂H₂ in various concentrations and to regulate the flow rate. Changes in the rates of O₂ uptake, CO₂ output, and C₂H₄ evolution associated with the ripening of banana fruits and the wounding of winter squash fruits were measured to check the performance of the system. The stimulation of respiration by exogenous C₂H₄, and the inhibition of respiration and C₂H₄ evolution by a high concentration of CO₂ were measured with sweet potatoes and peaches, respectively. The rates of change of the gases corresponded to well-known physiological responses to given conditions of flow gas in every sample tested. CO₂ output from the sample materials could be measured even in the flow gas containing a high concentration of CO₂, up to 60%. C₂H₄ evolution could be measured directly in the presence of external C₂H₄. Analysis of the response of fruit and vegetables in gas metabolism, to various gaseous environments of the system was satisfactory.

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