Japan Agricultural Research Quarterly: JARQ
Online ISSN : 2185-8896
Print ISSN : 0021-3551
ISSN-L : 0021-3551
Volume 48 , Issue 3
Showing 1-13 articles out of 13 articles from the selected issue
REVIEWS
Agricultural Engineering
  • Tsukasa TESHIMA, Takashi GOTOH, Yasuroh SUGIURA, Hiroyuki TAKAHASHI, K ...
    2014 Volume 48 Issue 3 Pages 253-259
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    In fundamental tests, we revealed that work power could be estimated based on measured values for engine speed and exhaust-gas temperature during the operation of an agricultural tractor. Based on these results, we developed a prototype which indicates the operating conditions to the operator to reduce the fuel consumption of agricultural tractors. This device employed five operating areas according to engine speed and work power and was designed to indicate changes in operating conditions (travel speed gear, PTO gear and engine speed) to ensure the tractor would operate within a region enabling high fuel efficiency and low exhaust-smoke density. The device was mounted on a 24 kW tractor, and indoor tests, rotary tillage tests, mole drainage tests, fertilizing tests and inter-row cultivating tests were all conducted. Consequently, by following the notification of the device, fuel consumption was reduced by approx. 15% at a power ratio of 55-65% (the ratio of work power to maximum PTO output), approx. 25-30% at a power ratio of 35-40% and approx. 35-45% at a power ratio of 20% with full throttle. Fuel consumption was also reduced by approx. 10% at a power ratio of 25-30% and approx. 10-25% at a power ratio of 10-15% with 50% throttle.
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  • Satoshi YAMAMOTO, Shigehiko HAYASHI, Hirotaka YOSHIDA, Ken KOBAYASHI
    2014 Volume 48 Issue 3 Pages 261-269
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    A stationary robotic strawberry harvester, combinable with a movable bench system, was developed. Initially, the features of strawberries, such as the visibility of fruit, the picking force required, and spectral reflectance were investigated. Subsequently, a machine-vision system was constructed, comprising units to measure position and coloration respectively. Considering the visibility of strawberry fruit, these units were optimally located to detect mature fruit and estimate their coloration. White, red, and green light-emitting diodes were installed for more accurate coloration measurement. The average error was 5.4%, and its standard deviation was 10.8%. We developed an end-effector with three functions: 1) to prevent the fruit adjoining the target fruit from being touched during the approach, 2) to force adjoining fruit away from the target fruit during the picking motion, and 3) to remove peduncles from harvested fruit, as done manually. The performance test confirmed that the stationary robotic harvester outperformed the conventional robots, namely, the harvester achieved a stable high harvesting success rate of 67.1%, and was able to successfully remove the peduncles from 88.0% of the harvested fruit.
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Horticulture
  • Masayoshi NAKAYAMA
    2014 Volume 48 Issue 3 Pages 271-277
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    The coloration pattern of flower tissue affects the commercial potential of floricultural plants and is also a subject of fundamental biological interest. Transposon insertion or excision and post-transcriptional gene-silencing are well-studied mechanisms involved when flower color patterns form. In this paper, I present a research strategy to understand the mechanisms that govern the formation of flower color patterns. First, I discuss the significance of flower color pattern-formation research and then go on to describe a research system in the following six sections: Observation of flower patterns, Comparison of pigment components, Gene expression analysis, Regulation of target gene expression, Genomic structure, and Factors that can change color pattern-formation. In these sections, reference is made to my own studies on the marginal picotee pattern of Petunia flowers. Post-transcriptional gene-silencing of the chalcone synthase gene is responsible for the formation of white tissue in the white marginal picotee pattern in Petunia flowers. The unusual genomic structure of chalcone synthase is probably related to the operation of position-specific post-transcriptional gene-silencing. In the colored marginal picotee pattern of Petunia flowers, the higher expression of flavonol synthase is a responsible for the central white tissue formation. I also provide a research perspective from which to resolve the remaining questions.
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ARTICLES
Agricultural Environment
  • Tomoko KOJIMA, Norikuni OKA, Toshihiko KARASAWA, Keiki OKAZAKI, Shotar ...
    2014 Volume 48 Issue 3 Pages 279-290
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    Crop growth was enhanced in fields previously cultivated with host plants colonized by arbuscular mycorrhizal fungi (AMF), compared with fields previously cultivated with non-mycorrhizal plants. To clarify the effect of previous cropping on the community structure of AMF in soybean roots, soybean were grown in fields which were cultivated after mycorrhizal plants, non-mycorrhizal plants, or left in uncropped condition over three years (in 2004, 2006, and 2007) in two different soils (Thaptoupland Wet Andosol and Low-humic Andosol). The partial region in the 18S rDNA of AMF from soybean roots was amplified by a nested PCR method using primers specific for AMF and sequenced. The sequence homology search and phylogenetic analysis revealed that the AMF community in soybean roots was unaffected by the preceding crop. Further, it was shown that the AMF phylotype “Glo-B1”, which included Glomus sp. ZJ (AB076344), was the most frequently detected, irrespective of the preceding cropping system. However, in 2007, the community structure of AMF in the soybean roots from the Low-humic Andosol field, which had been used as grassland for several years, was relatively different from that of the Thapto-upland Wet Andosol fields. It was implied that the AMF community could be affected by environmental condition or long-term vegetation.
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  • Sunao ITAHASHI, Masahiro KASUYA, Ryoji SUZUKI, Kaoru ABE, Kenji BANZAI
    2014 Volume 48 Issue 3 Pages 291-298
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    Commercial swine production can cause local water pollution if effluent water containing high levels of nitrogen (N), phosphorus (P), pathogen and heavy metals is discharged, but the actual status remains poorly documented. We thus selected zinc metal (Zn) as a tracer and conducted water quality observations in a rural river of Japan to reveal the significance of mid-sized swine farms on Zn pollution there. Results showed that one farm was the major contributor of Zn load in watershed, corresponding to 82% of total Zn load at a normal stage of water, which was apparently attributable to insufficient wastewater treatment at the farm. Consequently, the Zn concentration at the outlet was estimated at 37 μg L–1, revealing a significant ecological risk at 9.1% to aquatic organisms. We then analyzed the effectiveness of improved wastewater treatment of the farm and found that it had a plausible capacity to keep Zn concentration at the outlet below the environmental quality standard level (30 μg-Zn L–1) and the ecological risk at a safety level (<5%) as well. Based on these results, we concluded that since a swine farm could be a significant source of pollutants in rural areas, appropriate treatment of wastewater would be essential to sustain the potential pollution by Zn.
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  • Tsugiyuki MASUNAGA, Akira KAMIDOHZONO, Abdul Waris NEZAM, Sayed Azmar ...
    2014 Volume 48 Issue 3 Pages 299-306
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    Paddy soil properties in 20 villages in Nangarhar province, East Afghanistan were investigated. The soils, which were mostly classified as sandy loam or loam, were alkaline and contained carbonate ranging from 4.9 to 16.9 g C kg–1. The average total N and organic C, (0.36 N and 6.2 C g kg–1) was low compared to the average values in tropical Asian paddy soils. Calcium was the predominant exchangeable cation followed by Mg, K and Na in that order. The available P (Olsen-P) content was 20.7 mg P2O5 kg–1 on average and did not vary significantly throughout the study area, while the available Si content, (261 mg SiO2 kg–1) was comparable with the level in tropical Asia. The available micronutrients (DTPA-TEA extraction) Fe, Mn, Cu and Zn, were 35.9, 9.6, 4.75 and 0.33 mg kg–1 on average. The paddy soil properties were generally low in fertility compared to those in tropical Asia, while the available P and Zn contents were deficient for rice growth. Paddy fields in Nagarhar province could be divided into groups according to the location. The paddy soil properties varied in Kabul and Kunar watersheds and were influenced by spot distribution of different types of parent materials such as limestone, dolomite and lava.
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Agricultural Engineering
  • Shigehiko HAYASHI, Satoshi YAMAMOTO, Sadafumi SAITO, Yoshiji OCHIAI, J ...
    2014 Volume 48 Issue 3 Pages 307-316
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    This paper describes the development of a movable strawberry-harvesting robot that can be mounted on a travel platform, along with its practical operation in a greenhouse. The harvesting robot can traverse and enter an adjacent path and picking is performed with the travel platform halted on the travel path. Machine vision is used to detect a piece of red fruit and calculate its position in the three-dimensional space, whereupon its maturity level is assessed according to an area ratio determined by classifying the whole fruit into three areas: ripe, intermediate, and unripe area fractions. Sufficiently mature fruit are picked by the end-effector by cutting the peduncle. During operational tests in a greenhouse, our machine vision algorithm to assess maturity level showed a coefficient of determination of 0.84. Setting the maturity level parameter at 70 or 80% resulted in higher shippable fruit rates than the setting of 60%, because small unripe fruit positioned in front of larger ripe fruit were successfully skipped in the former case. Our results showed that a higher shippable fruit rate could be achieved later in the harvest season, reaching 97.3% in the test in June. The successful harvesting rate and work efficiency were 54.9% and 102.5 m h–1, respectively.
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Food Technology
  • Toyozo SATO, Mutsuo AOKI, Takayuki AOKI, Masaharu KUBOTA, Takashi YAGU ...
    2014 Volume 48 Issue 3 Pages 317-329
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    The morphology of 18 and seven species of fungi isolated from spoiled bean sprouts of Vigna spp. and soybean in Japan were respectively described, and DNA barcode markers of most isolates were sequenced to confirm the morphological identification. Fifteen and five species were isolated for the first time from Vigna spp. and soybean sprouts, including their ingredient grains, respectively. Globisporangium ultimum var. ultimum was newly recorded from the mung bean and most isolated fungi seemed to originate from the grains. Approximately 70% of isolates are recognized as plant pathogens and at least 14 species are known to be seed-borne. Inoculation experiments with representative strains of each species are needed to estimate the risks to bean sprout production and crop protection. Some strains of Fusarium graminearum isolated from the soybean were already reported as producing high concentrations of deoxynivalenol. Aspergillus flavus, which was found in mung bean sprouts, is a well-known aflatoxin producer. The ingredient grains should be imported after complete sterilization to avoid hazards; not only to bean sprout production but to human health. The effects of previously used sterilization techniques should be re-examined with the strains of various fungi isolated in this study to make them more practical.
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Agricultural Economics
Horticulture
  • Yuichi MATSUMOTO, Tomoko ISHIKAWA, Makoto MIYAGI
    2014 Volume 48 Issue 3 Pages 343-347
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    ‘Ibaraking’ is a new F1 melon (Cucumis melo L.) cultivar with green-fleshed fruit, high fruit growth ability under low-temperature conditions, high total soluble solid (TSS) content, and a long shelf life. It was developed from a cross between 2 parental lines P2 and P32 at the Plant Biotechnology Institute, Ibaraki Agricultural Center, Ibaraki, Japan. The parental line, P2, was fixed by self-pollination of a line selected from somaclonal variants of a cultivar ‘Andes,’ while another line, P32, was fixed by self-pollination of a cultivar ‘Earl’s Seine Natsu 2.’ The fruit characteristics of ‘Ibaraking’ were compared with those of the common melon semi-forcing culture cultivars ‘Andes-5’ and ‘Otome,’ from 2005 to 2007, in semi-forcing culture by creeping cultivation. In ‘Ibaraking,’ low-temperature fruit growth ability and external appearance were equal to those of ‘Otome’ and exceeded those of ‘Andes-5,’ while the TSS content was similar to that of ‘Andes-5’ and exceeded that of ‘Otome.’ With regard to shelf life, ‘Ibaraking’ was superior to ‘Otome’ and equal to ‘Andes-5.’ In response to Fusarium wilt of melon, the most severe melon disease, ‘Ibaraking’ demonstrated resistance to races 0 and 2. These responses were identical to those of ‘Andes-5’ and ‘Otome.’ Therefore, we conclude that ‘Ibaraking’appears a more suitable cultivar in semi-forcing culture by creeping cultivation in Ibaraki prefecture, Japan.
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Animal Husbandry
  • Hiroshi KONDO, Godfrey MUSOKE, Herman SSEKIWUNGA, Shinichi HATAMA, Yos ...
    2014 Volume 48 Issue 3 Pages 349-353
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    Pneumocystis pneumonia was identified in two female (cases 1 and 2) and a male (case 3) Boer cross goat kids aged 3 months on a farm in Uganda. This was fatal in cases 1 and 2, with symptoms of coughing. Severe infestation with Haemonchus contortus was found in the euthanized case 3. Histology revealed numerous Pneumocystis organisms in cases 1 and 2, but fewer in case 3. Although macrophages reactive to the organisms were observed in all cases, the lung lesions were not infiltrated with lymphocytes in cases 1 and 2. Polymerase chain reaction analysis for Pneumocystis DNA identified five genetic clones in case 1. This diversity may be due to repeated infection from other goats, and may also be associated with selective pressure from the innate immune system activated by mild Haemonchus infestation in young kids.
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Forestry
  • Fumio KAWAMURA, Nur Syahirah SAARY, Rokiah HASHIM, Othman SULAIMAN, Ko ...
    2014 Volume 48 Issue 3 Pages 355-362
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    Subcritical water extraction of low-molecular-weight phenolic compounds from oil palm biomass (trunk, bark, petiole, rachis, leaves, empty fruit bunch fiber, midrib spine leaflets, stalk of fruit bunches, flesh, kernel shells, and albumen) was conducted. It was elucidated that gallic acid, protocatechuicaldehyde, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillic acid, syringic acid, vanillin, syringaldehyde p-coumaric acid and ferulic acid, all of which could be used as 2-pyrone-4,6-dicarboxylic acid (PDC) precursors, were contained in all parts of oil palm, although their composition differed. The peak yield of p-hydroxybenzoic acid was obtained among the PDC precursors. With regard to extraction conditions, temperature: 200°C, time: 20-60 min, and liquor ratio: 50-125 were the most efficient. The kernel shell exhibited the highest yield of PDC precursors, followed by the trunk, empty fruit bunch fiber, and bark. The results of our study indicate the oil palm is a potentially valuable source of PDC precursors.
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  • Yasuhiro YOKOTA, Kazuhiro HARADA, ROHMAN, Nur Oktalina SILVI, WIYONO ...
    2014 Volume 48 Issue 3 Pages 363-377
    Published: July 01, 2014
    Released: July 31, 2014
    JOURNAL FREE ACCESS
    The State Forest Company of Indonesia launched its Company-Community Forestry Partnerships system on the island of Java in 2001 (PHBM system). We examined the PHBM’s effects on the economic lives of participating villagers through a case study in Madiun, East Java. We specifically examined the potential and limits of the PHBM’s contribution to villagers’ livelihoods by quantitatively evaluating (i) the system’s impact on household livelihoods and (ii) the continuity of its impact. Of households engaging in PHBM, 45.6% had more than half their arable land in the forest, and 10.0% of households had arable land only in the forest. The bulk of non-timber forest products, mostly fuelwood, was collected in the forest. Among villagers earning an income, 12.2% earned more than half via the PHBM, which was the only source of cash income for 2.2% of the engaged villagers. For some households, PHBM has helped significantly improve their livelihoods. However, the benefits derived from the PHBM were tempered by problems of quality, quantity, and continuity. The benefit of the system could be increased by providing preferential opportunities (to access farmland in the forest and/or cash income) to small-scale or impoverished farmers by improving the usage of intercropping land under planted trees, and promoting small business as a group enterprise.
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