Gynoecious inbred lines of balsam pear plants (Momordica charantia L.) were improved from cv. Aochu-naga. The plants with a large percentage of female flowers (high-female type) were chosen from the breeding material line (LCJ980120), then the generations of these plants were advanced by crossing in the same pedigree or self pollination. In the second and the third generations, bisexual flowers were induced with foliar application of silver nitrate solution to obtain pollen for crossing. In the third generation, 27 gynoecious plants were found on 51 plants of 4 pedigrees. Plants with desirable fruit quality were selected from these gynoecious plants and 4 pedigrees were obtained by crossing in the same pedigree. These 4 pedigrees did not show monoecism, but all of the plants were gynoecious. As the gynoecious sex expression was partially dominant in hybrid plants between the gynoecious pedigree and the monoecious line (KBP1), it is suggested that gynoecious inbred lines are promising seed parents for high-female F₁ hybrids.

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The possibility of using wild blueberry Shashanbo (Vaccinium bracteatum Thunb.) as a rootstock for cultivating northern highbush blueberry in a warm region was investigated. The survival ratios of three different cultivars (‘Berkeley’, ‘Bluecrop’, and ‘Earliblue’) grafted on 3-year-old seedlings of Shashanbo plants were 85.7 to 100%. Furthermore, 41 cultivars included in highbush blueberries and rabbiteye blueberries were successfully grafted on seedlings of Shashanbo rootstock. There were no signs of incompatibility even four years after grafting, and anatomical observations of graft unions supported this result. The shoot growth and fruit weight of ‘Earliblue’ grafted on seedlings of Shashanbo rootstock were significantly higher than those of plants on their own roots. However, the shoot growth of ‘Earliblue’ grafted on rooted cuttings of rabbiteye blueberries (‘Homebell’ and ‘Tifblue’) was significantly higher than that of those on seedlings of Shashanbo rootstock. In addition, there were no differences in concentrations or component ratio of sugars and organic acids on any rootstock.
These findings suggest that Shashanbo has graft compatibility with blueberry and that seedlings could be used as a rootstock for cultivating northern highbush blueberries in southern Kyushu.

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Fruit setting, fruit thickening characteristics of the parthenocarpic tomato variety ‘Renaissance’ in spring, early summer, autumn and winter which are the blooming seasons of the main cropping system in Aichi prefecture were examined. Fruit setting percentage of ‘Renaissance’ in spring, early summer, autumn, winter was very high. There were no undergrown fruit and the parthenocarpic characteristics of ‘Renaissance’ were very strong in these seasons. In ‘Renaissance’, fruit weight and days required till harvest were not influenced by production of seeds or treatment with 4-chlorophenoxy acetic acid (15 mg/L). These results suggested that productivity of ‘Renaissance’ was higher than that of the non-parthenocarpic tomato variety.

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We investigated the effects of summer pruning and fertilization on the absorption of nutrients the following autumn when ‘Muscat of Alexandria’ grape was grown under forcing culture from December, using a soil-less culture system. After harvest between June and July, both summer-pruned and non-pruned vines received fertilizer treatments at three different levels (15 g, 10 g and 5 g nitrogen per m², 15 g, 10 g and 5 gN). Fertilizer levels of all treatments in the autumn were fixed at the same level (12 gN). The color of leaves was significantly deeper from September to middle October after 15 g and 10 gN treatments compared with that after 5 gN treatment. Lignifications of shoots were most rapid after 10 gN treatment, followed by 15 gN treatment, and delayed after 5 gN treatment. Nitrogen applied in the autumn was more rapidly absorbed after 5 gN than after 15 g or 10 gN treatments. Most of the nitrogen disappeared by the beginning of December after 5 gN treatment. On the contrary, after either 10 g or 15 gN treatment, nitrogen partly remained in the nutrient solution through December. Phosphate was absorbed in the autumn with the same pattern in all treatments, and had completely disappeared by the beginning of December. Potassium absorption after 5 gN treatment was more rapid and larger than that after 10 g or 15 gN treatment. However, in all treatments, potassium partially remained through December, differing from nitrogen. Between summer-pruned and non-pruned vines, there was no difference observed in the absorption of nitrogen, phosphate and potassium in the autumn. These results indicate that the higher-level fertilizer application in summer significantly decreased absorption of nitrogen and potassium delivered from fertilizer applied the following autumn.

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To clarify the effects of growing season and temperature on flower color in apricot and picotee flower genotypes of spray chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitam.), flower petal color of ray florets flowered under different growing seasons or temperatures was evaluated. Concentrations of anthocyanin and carotenoid in ray florets were also assayed. Apricot flower genotypes displayed a yellowish flower, decreased a* value and increased b* and h values under high temperature conditions. In picotee flower genotypes, the red region on the petal paled or disappeared under high temperature conditions, changing the proportions of picotee. There were two patterns for the expression of picotee phenotype, 1. genotypes in which the white region appeared at the tip of a red petal under high temperature. 2. genotypes in which the red region was located at the base of petal, and the region was increased at the optimal temperature. The two main anthocyanins, cyanidin 3-O-(6''-O-monomalonyl-β-glucopyranoside) and cyanidin 3-O-(3'',6''-O-dimalonyl-β-glucopyranoside), were detected in all genotypes, but the relative amounts changed depending on temperatures. However, the total amount of carotenoid was unaffected by temperature. These findings suggested that changes in the amounts of the two main flower pigments were the main reason for flower color changes in many apricot and picotee flower genotypes.

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A questionnaire about physiological disorders of Japanese persimmon (Diospyros kaki Thunb.) ‘Saijo’ sprouting from dormant buds was used to survey farmers in Shimane Prefecture. An increased prevalence of this physiological disorder was first noticed around 1995 and is now reported in more than 60% of the orchard investigated. The Ca, Mg, Mn, fructose and glucose concentrations in the branches of physiologically disordered trees was lower than that of sound trees. It was also observed that the tannin concentration in axillary buds increased in proportion to the degree of this physiological disorder, particularly in March. The tannin accumulated mostly in cells located at the basal part of bud meristems. In addition, cambium cells in physiologically disordered trees showed a lower cold tolerance.
In conclusion, the physiological disorder of Japanese persimmon ‘Saijo’ sprouting from dormant buds was caused by accumulation of insoluble tannin in the conductive tissues, which inhibited nutrient supply and water to the buds. It is also suggested that these physiological disorders might further deteriorate in the winter due to low temperatures.

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Tomato plants (Lycopersicon esculentum Mill., cv. House-Momotaro) were grown in a grower’s greenhouse (0.4 ha) using a commercial open rockwool system and a similar system equipped with a solution-recycling unit that we devised to reuse nutrient solution drained from the bed (closed rockwool system). In the closed system, the nutrient solution was prepared by adding tap water to drained nutrient solution collected in the mixing tank until the solution volume attained a given level, then concentrated fertilizer solutions were added until the EC of the solution reached a preset value. The elemental composition in the supply solution was adjusted at monthly intervals based on the chemical analysis of drained nutrient solution. Concentrations of nutient elements in the supply solution were not significantly different from those expected from its EC value and elemental concentrations in the fresh nutrient solution with the same EC value. The fruit yields of the two cultivation systems were not different. The closed system showed 22 to 47% reduction in the amount of nutrient elements applied and 33% reduction in the fertilizer cost compared with the open system. Thus, the closed rockwool cultivation system that we devised can be applicable to the large-scale commercial production of tomatoes. Problems to be resolved before this system is commercially introduced are discussed.

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Effects of the time of flowering and harvest as well as the size of the fruit on the compositions of the fruit and the processed Japanese apricot liqueur (ume liqueur) were determined in the Japanese apricot (Prunus mume Sieb.et Zucc.) ‘Nanko’. Concentrations of citric acid and sorbitol in the flesh with skin increased until just before the day of full ripening and dropping stage. Growth of fruit that bloomed early was later than that of fruit that bloomed late. The fruit that bloomed early had lower concentrations of citric acid and sorbitol in the flesh with skin than fruit that bloomed late. Concentrations of citric acid and phenolics, antioxidant activity, and browning strength of the ume liqueur increased when the harvest time was delayed to just before the full ripening stage. When fruit was harvested on the same day, the larger fruit showed greater concentrations of citric acid, malic acid, sorbitol and β-carotene in the flesh with skin. Concentrations of citric acid and sorbitol and the browning strength of ume liqueur were higher when fruit above 2L size were processed. These results show that harvest time and fruit size influence the concentrations of components and the quality of both the fruit and the ume liqueur, suggesting that well-grown and enlarged fruit are most suitable for making ume liqueur.

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The pollination efficiency between Melipona quadrifasciata anthidioides (Neotropical stingless bee) and Bombus terrestris (bumble bee) was evaluated in eggplants (variety Senryo), cultivated in a greenhouse. The house was divided into two sections (section A and B), and twenty-four pots of eggplants were grown per section. The colony of M. quadrifasciata and B. terrestris was introduced into section A and B during the period of 29. Dec., 2004-1. June, 2005, respectively. The total fruit produced by each treatment was weighed to estimate the average production in kilograms per plant. The total number of fruit without commercial value in each treatment was also recorded. There was no significant difference between treatments in either quantity or quality of fruit. It was concluded that the use of M. quadrifasciata anthidioides as a pollinator of greenhouse eggplants could be an alternative to the use of B. terrestris or Apis mellifera (honey bee). However, further research observations are needed in a large greenhouse to develop techniques for commercial use of M. quadrifasciata.

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To study the effect of seed number per berry on berry ripening in highbush blueberry, self-, cross- and open pollination were carried out on ‘Berkeley’ and ‘Dixi’ in order to produce berries that contain various numbers of seeds. Seed number per berry was higher after cross-pollination than after self- or open pollination, and the number of large brownish seeds was higher than that of small white seeds after each type of pollination. Multiple regression analysis using number of large brownish seeds and small white seeds per berry as dependent variables, while days to ripening from flowering as independent variable showed significant multiple regression coefficients in all treatment on two cultivars. The standardized partial regression coefficient of large brownish seed number per berry was higher than that of small white seed number, except for self-pollination in ‘Dixi’. Further, the percentage of large brownish seeds that germinated was higher after cross-pollination compared to that after self- or open pollination, and significantly correlated with the standardized partial regression coefficient. Therefore, the number of viable large brownish seeds per berry seemed to be a more important factor in determining berry ripening of highbush blueberry.

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To produce seedless loquat fruits, the effects of GA₃ and CPPU applications on growth and quality of seedless fruits in the triploid loquat ‘Tanaka’ strain were investigated. The triploid seedless fruits equal in weight to that of ordinary fruits with seeds grown on diploid ‘Tanaka’ were produced at harvest time by dipping flower and fruit clusters in an aqueous solution of 200 ppm GA₃+20 ppm CPPU twice, at flowering time (the first treatment) and between 27 to 58 days after the first treatment (the second treatment). However, the annual concentration of soluble solids in triploid loquat seedless fruits was lower than that of diploid loquat fruits with seeds. The triploid seedless fruits had a longer shape and higher fruit shape index (fruit length/fruit width) than diploid fruits with seeds. The tissue size of the enlarged calyx base and the internal space of the calyx tube of triploid seedless fruits increased to about 2 times as large as those of diploid seeded fruits, in addition, the locule size of the seedless fruits was slightly longer than 1 cm in diameter. However, the locule was only 7% of total volume of the seedless fruits. Flesh thickness at the equator of the seedless fruits grew to about 2 times that of fruits with seeds, the flesh weight increased by approximately 20%, and the edible portion increased to 90% of total weight of the seedless fruits. The increase in flesh thickness resulted from both cell division and cell enlargement.

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To unify the time of shoot development in Odontioda orchid, effects of the size of shoots that were decapitated on the time of shoot development and flowering was investigated. Healthy shoots developed from more than 80% of plants within 40 days after decapitation, even if the size of shoots decapitated differed. The percentage of flower-stalk emergence of developed shoots ranged from 60 to 87%, and there were no differences among shoot sizes. There was no difference in time of flower-stalk emergence among shoot sizes. When the plants that did not flower and developed secondary shoots were selected and the secondary shoots of those plants were decapitated, new flower-stalks emerged from 70% of those plants within 30 days after decapitation.
In conclusion, despite difference in the sizes of shoots that were decapitated, decapitation of developing shoots stimulated emergence of new shoots, and the development of the shoots was uniform. Moreover, when the shoots of the plants that did not flower last season were decapitated, new flower-stalks emerged from back shoots. Thus, it was demonstrated that decapitation of the developing shoot was useful for not only unifying the developmental stage of shoots but also improving flower pot productions.

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The mechanism of flower thinning by ethephon treatment was investigated in the Japanese pear ‘Hosui’. Ethephon at 250 ppm was applied to flower clusters 7 days before full bloom (DBFB). After ethephon treatment, the proportion of flowers in which the abscission layer was formed at the juncture between peduncle and inflorescence axis was increased from 1 DBFB to 2 days after full bloom (DAFB). In contrast, there was no abscission layer formed at this juncture in control flowers at 2 DAFB. Ethylene evolution from the ethephon-treated flower clusters was increased markedly. Abscisic acid (ABA) and 1-aminocyclopropane-1-carboxylic acid (ACC) concentrations in inflorescence axis, peduncle or flower were also increased by ethephon treatment. However, there were no differences in the indoleacetic acid (IAA) content between ethephon-treated flower clusters and control flower clusters before 1 DBFB. When ethephon at 250 ppm was applied to flower clusters at 12 or 4 DBFB, or 2 DAFB, ethylene evolution from the flower or fruit clusters was found to differ with the treatment time. The fruit set percentage at 23 DAFB tended to decrease with increasing ethylene evolution following ethephon treatment. Together, the results suggest that ethephon treatment exerts a thinning effect by promoting the formation of the abscission layer through increased ethylene evolution, and that the thinning effect depends on the ethylene evolution following ethephon treatment.

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To establish the optimal transportation method for peach fruit harvested at the fully ripe stage, we examined changes in fruit size, quality and flesh firmness during maturation, and the influence of harvesting ripeness and storage temperature on fruit keeping quality. In addition, we investigated truck transportation. The harvesting stage for fully ripened fruit transportation would be just before reaching the peak of fruit enlargement, indicated by fading of the green color of the peach skin in the stalk cavity. The time was comparable to the fourth to sixth day after the harvest time for machine sorting of fruit, and on the second to third day after the harvest time for hand sorting. The fully ripened fruit softened quickly at room temperature, but retained flesh firmness when stored at less than 5°C. The freshness retention period of the fully ripened fruit was about two days at room temperature, and about ten days at 0°C. When the fully ripened fruit harvested at the optimum time noted above were transported between Okayama and Kyoto under a low-temperature condition such as 5°C or less, the firmness and taste of fruits were sufficiently maintained and were not spoiled.

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Effects of trunk girdling and mulching with reflective plastic film during development on postharvest fruit softening were studied in ‘Tonewase’ Japanese persimmon for a couple of years. In addition, usefulness of packaging in an improved carton after 1-methylcyclopropene (1-MCP) treatment to suppress fruit softening was investigated. Softening of untreated fruit varied each year in severity and interval until softening. Trunk girding stimulated fruit color development on the tree and fruit softening after harvest every year. Packaging fruit from trunk-girdled tree in the improved carton box showed a limited inhibitory effect on fruit softening in 2004 only. 1-MCP treatment after harvest markedly inhibited fruit softening. Mulching with reflective plastic film from middle August until harvest time stimulated fruit color development on the tree in all years tested. Mulching stimulated postharvest fruit softening in 2002, but not in 2003 or 2004.

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Wrong:Washa
p.79, right column, line 4
p.82, left column, line 9
p.82, right column, line 2
p.83, right column, line 28
Right:Wasna

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