This study was investigated to clarify the influences of the onset of forcing, cultivar, gibberellin treatment and hand pollination on the harvesting time, yield and berry quality of forced blueberry using highbushblueberry 'Weymouth' and 'Northland', and rabbiteyeblueberry 'Tifblue'. Experiment 1 : Influences of the onset of forcing on the flowering, harvesting time, berry set percentage and berry quality. The faster the blueberries flowered and harvested, the earlier the forcing began. However, in both cultivars of 'Weymouth' and 'Northland', no difference was observed between the plot on Jan. 18th and the one on Feb. 1st. The berry set percentages of all forced plots by open pollination under protected cultivation were lower than that of open field plots. Experiment 2: Hand pollination and gibberellin treatment on the harvesting time, berry set percentage and berry quality. Through hand pollination, the harvesting time accelerated, the berry set percentage increased, berry size became larger and berry yield augmented in both cultivars of 'Northland' and 'Tifblue'. This occurred regardless of the transferring time to the greenhouse. Furthermore, the gibberellin treatment promoted the berry set, but its percentage changed by the treated time. The gibberellin treatment delayed the harvesting time and retarded the berry enlargement compared with that of hand pollination.

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The effects of stalk and leaf treatment with ethephon on sex differentiation of melon, particularly its effects on hermaphrodite flower development and subsequent fructification and fruit quality, were investigated. 1. Treatment at the seeding and cotyledon leafing stage did not induce hermaphrodite flower formation on the main stem or lateral shoots. 2. Treatment with 125ppm ethephon at the 1.5 leafing stage resulted in the formation of some hermaphrodite flowers on the main stem. Treatment with 500ppm ethephon, however, markedly suppressed the formation of such flowers on lateral shoots below the 15th node. 3. Ethephon treatment at 2.5 leafing stage resulted in hermaphrodite flower formation on 10th to 13th the main stem, but the number of this kind of flowers decreased markedly on the lateral shoots. 4. Treatment with 25-125 ppm ethephon at 3.5 leafing stage results in a high incidence of hermaphrodite flower formation on the 14th to 16th main stem nodes, irrespective of the season in which the plants were cultivated. 5. The hermaphrodite flowers which were formed in ethephon-treated plants led to good fruit growth and allowed slightly earlier harvest. The sugar content was highest in one fruit treated with 50 ppm ethephon. ethephon, hermaphrodite flower ,main stem node,sex expression, 'Shirayuki' melon

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Strawberry 'Toyonoka' was planted in Wagner's pots, which were then placed in water tanks whose temperature was set at 5℃, 9℃, 13℃, 17℃, 21℃ or 25℃. The influence of root zone temperature on the growth of the plant was examined. 1. Growth was better at high root zone temperatures over the 17℃. The ratio of the top-root weight became higher at higher temperatures. 2. The fruit yield was maximum at root zone temperature of 21℃. The sugar content and acidity decreased at 5℃ root zone temperature. 3. The photosynthesis rate was maximal at root zone temperature of 17℃, and was much lower at temperatures below 9℃. 4. The potassium and calcium levels in leaves rose at 21℃ root zone temperature. The phosphorus and magnesium levels decreased with time, but were higher in the root zone temperatures of 13℃ than in any other treatments at all points of measurement. 5. These results suggest that the optimum root zone temperature for strawberry 'Toyonoka' growth in this growing period is17-21℃.

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This study evaluated the use of electrolyzed acidic water (equivalent to sodium hypochlorite water designated as a food additive) as a disinfectant for the agricultural industry. In the agricultural material disinfection experiment, the efficacy of commonly used neutral calcium hypochlorite was compared with that of electrolyzed acidic water. When the materials used for solution culture of Mitsuba (Japanese honewort, Cryptotaenia japonica Hassk) were disinfected by 10-minute immersion treatment, no bacterial growth was observed in either treatment. In the seed disinfection experiment, a combination of warmed electrolyzed alkaline water and electrolyzed acidic water treatments was compared with a 500- or 1000-fold dilution of the commonly used Benomyl wettable powder (Registered Chemical No. 14051 by the Japanese Ministry of Agriculture, Forestry and Fisheries). The results demonstrated fast and reliable disinfection with no adverse effect on the germination percentage observed. The conventional disinfectants are highly concentrated for distribution purposes and require special care in handling and troublesome dilution at the point of use. On the other hand, electrolyzed water is dispensed in a readily usable condition from a water electrolyzer, which simplifies preliminary adjustment and drainage treatment as well as reduces potential hazards associated with the available chlorine concentration. Therefore, electrolyzed water could be used as an effective disinfectant for agricultural materials and seeds.

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The purpose of this study is to investigate the sedimentary soil which could be worth using as soil amendment in agricultural field, in the Sameura Dam in Kochi prefecture (SSD). Chingensai (Brassica campestris var. chinensis) were cultivated in the green house soil (GHS), GHS mixed with SSD and SSD only. Sweet corn (Zea mays L.) were cultivated in the upland field soil (UFS) and in the field coating with the SSD on UFS. The growth and yield of the crops were observed, and the chemical analyses of these samples were investigated among these soil plots. Results suggested that SSD could be useful for dilution of nutrients in the range of optimum crop growth in the salt accumulated soil such as continuous green house soil. Furthermore, SSD could be used as soil dressing to the field that have shallow top soil layer, but it is more necessary to examine the physical properties and status of organic matter of treated field soil because the sand content of SSD was high and the total carbon and nitrogen were low.

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he community of oribatid mites and its seasonal prevalence at 4 different vegetations, i.e., 1) broad-leaved forest, 2) coniferous forest, 3) grassland, and 4) grassland, adjoining to the forest , were studied at the Rakuzan Park in Matsue (lat. : 35°29' N ; alt. :40〜60m), southwestern Japan. Throughout the present study, 84 species (1,654 individuals) at 1), 72 species (1,308) at 2), 87 species (3,972) at 3), and 79 species (2,350) at 4) were collected, showing that 3) was the richest community structure of oribatid mites among 4 vegetations. The population of oribatid mites decreased from spring to summer, and the number of species dropped down in summer at 1) and 3). At 3) population and the number of species increased again toward winter, while these were remarkably fluctuated throughout a year at 2) and 4). As dominant species, Mixacarus exilis and Oppiella nova at 1), and Eohypochthonius cassisetigerand M. exilis at 2) were recognized. No prominent dominant species was recorded from 3) and 4). Most of dominant species were usually found at the upper stratum (0〜3cm deep from the ground surface), irrespective of different vegetations. However, M. exilis, O. nova, Gen. sp. 1 (Oppiidae), E. cassisetiger, Oppia neerlandica, Vepacarus hirsutus, etc. were also distributed at the middle (3〜6cm) and lower (6〜9cm) strata. Among those species which were dominant at the upper stratum, M. exilis, O. nova, Gen. sp. 1 (Oppiidae), Oppia arcualis, O. neerlandica, Ceratozetes japonicus seasonally migrated from the upper stratum to the middle and lower strata, presumably due to thermal change in substrata. Average species diversity was higher at the upper stratum than at the middle and lower strata at 1), 2) and 4). Similar tendency was also confirmed at 3), except in summer. The values of average species diversity and relative diversity were relatively high in spring at all 4 vegetations, suggesting that community structure at each vegetation was mostly complicated and stable in this season. The community structure of oribatid mites was similar between 3) and 4), but greatly differed between 2) and 4).

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This paper describes the development of an autonomous steering rice transplanter which utilizes a color image processing technique for self-guidance in paddy fields. In the paper(I), it was reported that the rice transplanter was able to go straight 15 m in the first row and turn into the second row without an operator. The paper (II) presents that the rice transplanter is able to go straight 30m in the first row by using video camera zooming system. However, as the distance was too far to communicate by wireless modems used in this experiment, it requires the wireless modems that can communicate in the wider area.

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This article is based on primary data generated from household surveys in two villages of Bangladesh. The study compares the household income, its distribution and poverty situation in villages with a high level of adoption of modern technology and a low level of adoption of that technology. The findings of the study indicated that rice yield, agricultural production and household income were considerably higher in a modern-technology-adopting village than in a traditional-technology-adopting village. However, income inequality was found less in a high-technology-adopting village than in low-technology-adopting village. Furthermore, poverty measures also showed that the incidence of poverty was lower in a high-technology-adopting village than in a low-adoption village.

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For the purpose of determining the origin of evergreen azalea cultivars, the Edo-kirishima, Kurume azalea and Miyama-kirishima cultivar groups were analyzed using PCR-RFLP marker of chloroplast DNA that had been obtained in the previous study of wild evergreen azalea populations of Kirishima mountains. Most of Edo-kirishima and Kurume azalea cultivars possessed a banding pattern of Rhododendron kaempferi and the less possibility could be indicated in the contribution of R. kiusianum to the cultivars formation of these groups. On the other hand, Miyama-kirishima cultivars that were selected from wild population of R. kiusianum possessed each banding patterns corresponding to the each source mountains date.

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