Tissue culture costs of 3 superior wild clones of Prunus sargentii Rehder (PS 1, PS 2, PS 3) for the Japanese traditional handicraft industry was studied using sprout axillary buds. The overall degree of micropropagation difficulty of the 3 clones was in the order of PS 3, PS 2 and PS 1 judging from shoot propagation, rooting, plug and acclimation. The estimated cost of the plug was 304 yen (PS 1), 485-646 yen (PS 2) and 509-680 yen (PS 3). PS 1 was propagated with1 or 3.16μM BAP, but PS 2 and PS 3 only propagated with 1μM BAP. Under shoot propagation with 1μM BAP, the rooting was only observed in PS 2. Rooting and shoot development under rooting conditions indicated different patterns of IBA response among 3 clones. The clonal differences of phytohormonal response among 3 clones are considered to be due to the physiological status and/or genetic background.

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Effects of low temperature treatment and plant age on flower bud formation were investigated in Chinese kale with white petals.
1. Flowerbud for mation was promoted by low temperature treatments (10/5°C, light/dark period). Moreover then odenumber decreased following low temperature exposure. The effects were stronger after two weeks of low temperature treatment compared to those after one week. 'Hakushin', 'Kairan-T' and 'Kairan-M' formed flower buds during four weeks of low temperature treatment, and 'Chugoku-kairan', 'Shirobana-kuroba' and 'Kairan-K' formed flower buds after the treatment.
2. Flower buds of 'Hakushin' and 'Kairan-T' were promoted by low temperature treatment one week after sowing. Those of 'Kairan-M', 'Chugoku-kairan', 'Shirobana-kuroba' and 'Kairan-K' were promoted by the treatment two weeks after sowing.
3. Flower buds of 'Hakushin' and 'Kairan-T' were slightly promoted by low temperature treatment of pregerminated seeds. However, the flower buds were more strongly influencd by the growing temperature than the treatment of pregerminated seeds.

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To estimate the relationship between free sugar contents and growth enhancement through symbiosis of arbuscular mycorrhizal (AM) fungi (Glomus fasciculatum and Gigaspora margarita), we investigated the changes in free sugar contents through AM fungus symbiosis in tomato (Licopersicon esculentum Mill., cv. Momotaro-T 93) seedlings.
Five weeks after inoculation, AM fungus infection level in a whole root system reached 17.6% in Glomus fasciculatum, while in Gigaspora margarita, 24.2%, although no major difference between noninoculated and inoculated plants appeared in the plant growth. Regardless of fungus species, total free sugar contents showed greater values in shoots, tap roots and branched roots of AM fungus-infected plants than in noninoculated ones; trehalose was detected in roots of plants infected with each fungus species. Twelve weeks after inoculation, exceeding noninoculated plants, AM fungus-infected plants gave greater values of plant height, proximal diameter of shoots, and dry weight of both shoots and roots, regardless of fungus species. Water contents of both shoots and roots showed similar levels among the treatments. AM fungus infection level showed 25.8% in Glomus fasciculatum, 38.2% in Gigaspora margarita. Total free sugar contents increased in shoots and tap roots of infected plants in both fungus species; the effect was pronounced more in Glomus fasciculatum than in Gigaspora margarita. Free sugar, which caused the increase in total free sugar contents, differed among the parts of the plants. Trehalose was detected in shoots and branched roots in Glomus fasciculatum-infected plants. These results suggest that increase of free sugar contents are closely associated with plant growth enhancement through AM fungus symbiosis in tomato seedlings.

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We examined the influence of nitrogen fertilization and irrigation on fruit quantity in container planting cultivation of the Japanese persimmon maekawajirou. The highest quality fruits of maekawajirou cultivated in containers were obtained by irrigating 3.0-5.0 liter/day/container of water and by applying 10g/year/container of nitrogen fertilizer. Use of nitrgen fertilizer until August of produced the highest quality fruits of maekawajirou in containers, Use of IB and NK compound fertilizer and organic fertilizer (Hanagokoro) produced the secondhighest quality fruits of maekawajirou in containers.

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To reduce the prevalence of illness and detect physiological disorders in their early stages, pathological diagnosis of plants is important. When a plant image stored as a large data file is sent, transmission takes a long time. To reduce transmission time, image compression is needed. The most widely used compression format for photographs is JPEG (Joint Photographic Experts Group). The advantage of JPEG is its high compression rate. A weak point is irreversibility; it is impossible to reproduce the image perfectly.
We use plant images for pathology diagnosis and investigated an algorithm to compress such images without loss of information. We adopted a method that separates the photographic image into useful parts (plant) and other parts (background), and stores and compresses only the useful part. The algorithm is as follows : I. Mask to get the plant information for diagnosis from a photographic image; 2. Delete the background; 3. Compress and store the image of only the plant image. We wrote a program to recognize and to mask the plants based on HSI (Hue, Saturation, Intensity). The program covers not only green vegetables, but also fruits. Furthermore, the program was investigated in combination with existing image compression techniques (for example, tiff and tga). We achieved a compression rate of about 45% compared with original photographs. We expect the compression rate to be increased in the future by optimizing the HSI parameters.

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In order to apply wheat (Triticum vulgare VILL.) seeds of winter habit to the late-summer sowing culture, the vernalization treatment method was carried out using water treated with ceramics.
The plant height and the growing speed were promoted with the low temperature treatment using water treated with ceramics instead of tap water, and the maximum tillering stage was faster than that using tap water in the pot test. On the other hand, in the field test, the tiller was promoted, and the number of stems increased with low temperature treatment using water treated with ceramics instead of tap water.
The heading period was accelerated by performing low temperature treatment using water on seeds. However, the difference of the heading date between the low temperature treatment using tap water and the low temperature treatment using water treated with ceramics was 2-3days.
The effect of treated water with ceramics on the yield component was observed to be greater than the control and treatment using tap water in the pot test, however, the difference of the yield of the treatment using water treated with ceramics and other treatments was not clear in the field test.

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The means of enhancing the growth of seedlings of Japanese persimmon (Diospyros kaki Thunb.) through inoculations of arbuscular mycorrhizal (AM) fungi [Gigaspora margarita (GM), Glomus aggregatum (ga), Glomus fasciculatum (gf), Glomus mosseae (gm) and Glomus sp. R-10 (gr)] were investigated.
Fifteen weeks after inoculation, plant height showed significantly higher values in AM fungus-inoculated plants (except gm) than in noninoculated ones; the effect was more pronounced in GM-, ga- and gr-inoculated plants than in gf-inoculated ones. The number of leaves and leaf area were superior in AM fungus-inoculated plants compared with noninoculated ones. The shoots of GM-, ga- and gr-inoculated plants had greater dry weight than did those in noninoculated ones, while for the dry weight of roots, GM-, gf- and gm-inoculated plants gave significantly greater values than did noninoculated ones. Although AM fungus infection occurred in all the seedlings inoculated, GM, gf and ga showed higher infection levels than gr and gm. The increase in P concentrations was confirmed in both tap and lateral roots of almost all infected plants. Consequently, it was clarified that both AM fungus infection level and plant growth enhancement through symbiosis differed with AM fungus species in Japanese persimmon seedlings.

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The effects of white light+UV-B and α-to copherol on skin colouring in apple cultivars were investigated. Apple cultivars used were 'Royal Gala' and 'Braeburn' growing in orchard of Massey University, New Zealand.
The colouring of apple fruit was promoted by UV-B. In whole fruit treatment, α-tocopherol application affected the apple colouring. However, in skin disk treatment, the effect of α-tocopherol was negligible.

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The purpose of this study was to investigate the effect of various kinds of purified water on the germination and growth of the hypocotyl in plants. Purified water used in this study was taken from Kagoshima City water, Fukuoka City water and Osaka City water.
The results were as follows : Treated Kagoshima City water and Fukuoka City water influenced the germination rate and germination coefficient of radish seeds.
The mean growth of the hypocotyl with treated Osaka City water was different than that with treated Kagoshima City water and treated Fukuoka City water.
Seedling growth was not different among the purified water groups treated with rocks for 5 days.

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