Japan Agricultural Research Quarterly: JARQ
Online ISSN : 2185-8896
Print ISSN : 0021-3551
ISSN-L : 0021-3551
最新号
選択された号の論文の9件中1~9を表示しています
REVIEW
Agricultural Engineering
  • Hirofumi YAMASAKI, Hirokatsu SHITO, Mitsuhiro HORIO, Ei SEKI, Shunsuke ...
    2019 年 53 巻 3 号 p. 149-157
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    In order to avoid severe injuries in the event of entanglement accidents during hand-fed threshing by use of head-feeding combine harvesters, we studied here the conditions required for the machinery to be developed, while obtaining farmers’ opinions and attitudes toward hand-fed threshing and measurement of lifting force by female users. To satisfy these conditions, we developed prototypes additionally equipped with an opening function of either the threshing drum cover or the pinching rod, and thereby verified ability to allow users to pull out the entangled hand with ease. We completed research and development in 2013, and current models of head-feeding combine harvesters equipped with this device are commercialized by four agricultural machinery manufacturers in Japan, spreading more than 6,000 units of 21 models.

ARTICLES
Crop Science
  • Haruki ISHIKAWA, Issa DRABO, Ousmane BOUKAR, Christian FATOKUN, Satoru ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 159-167
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    A comparative analysis of farmers’ preferences on improved cowpea varieties was carried out based on the data obtained from farmers’ participatory varietal selection and questionnaire survey undertaken in south-eastern Niger and north-central Burkina Faso. The grain yield was consistently the most important and common selection criterion for farmers in both countries, with a significant influence of other traits, including balance between grain and fodder yields, earliness, seed characteristics, and resistance to Striga gesnerioides in their variety selection process. In other words, if the variety had enough yield, the farmers’ selection of the variety was separated from the second criterion reflecting farmers’ demand specific to their social and environmental conditions, such as tradition, marketing, assets, rainfall, and biotic and abiotic stresses in the region. Key criteria for farmers’ variety selection were obtained as well as an understanding of the potential of participatory activities to improve strategies in cowpea breeding and dissemination targeting these regions.

Agricultural Environment
  • Susumu S. ABE, Takahiro HARADA, Hiroshi OKUMURA, Toshiyuki WAKATSUKI
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 169-179
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    In the present study, the multiple regression analysis of mass balance equations of seven major geochemical elements (Al, Fe, Ca, Mg, K, Na, Si), among rock, soil, stream water, and precipitation in a watershed was used to simultaneously estimate the rates of rock weathering (RWR) and soil formation (SFR) in two template forest watersheds of Central Japan that had different types of vegetation and bedrock. Our results revealed that Mt. Kasuga watershed (MKW) with a primary evergreen broadleaf forest and gneissic bedrock had lower RWR (1.51 t ha−1 yr−1) and SFR (1.37 t ha−1 yr−1) than those in Yata Hill watershed (YHW) with a semi-deciduous mixed forest and granitic bedrock (RWR = 1.83 t ha−1 yr−1; SFR = 1.79 t ha−1 yr−1). Based on the hypothesis that the vegetation effect on the watershed scale mass balance is negligible in a steady state ecosystem, we concluded that the bedrock type can be a main factor causing the difference in RWR and SFR, as gneiss in MKW had smaller amounts of mica and feldspars and is supposed to have the higher resistance than granite in YHW to chemical weathering.

Agricultural Engineering
  • Sai Hong ANH, Toshinori TABATA, Kazuaki HIRAMATSU, Masayoshi HARADA, L ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 181-190
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Van Coc Lake located in the Dan Phuong and Phuc Tho, Hanoi, Vietnam, has an area of 30.83 km2. It is usually dry and includes arable land and residential areas. However, to protect Hanoi City from catastrophic floods, in emergency situations, it receives the floodwater from the Red River as a regulating reservoir and drains the floodwater to the downstream Day River through the Day Weir. We performed numerical simulations to assess the movement of floodwater in this lake and evaluated the impact of floodwater on its residential areas. A two-dimensional depth-integrated hydrodynamic model was constructed to simulate inundation in this lake. The model was validated and the effects of Manning’s coefficient of roughness were examined. In case of emergency, it has to receive an inflow of 2,500 m3/s into the area. Inflow rates of 1,200 and 600 m3/s were also examined to compare the results. The simulation results indicate that this lake was entirely inundated in 13, 28, and 56 h by inflow rates of 2,500, 1,200, and 600 m3/s, respectively. Between 66% and 99% of residential areas were inundated. The areas with highest velocity were primarily focused behind the gate with a velocity of 1.5-1.8 m/s.

Food Science
  • Kaori FUJITA, Masataka SAITO, Bounsong VONGVICHITH, Katsumi HASADA, Ph ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 191-199
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Nine species of fish (Clarias batrachus, Clarias microcephalus, Anabas testudineus, Henicorhynchus siamensis, Puntius brevis, Rasbora aurotaenia, Channa striata, Channa gachua, and Esomus metallicus) and three types of shellfish (Viviparidae spp., Pomacea spp., and Unionidae spp.) available in Nameuang Village and in the capital city Vientiane of Lao People’s Democratic Republic were analyzed in terms of nutritional composition to investigate their value as food resources with the aim of improving the nutritional status in rural areas of the country. A total of 35 types of fish and shellfish were consumed in the surveyed village. Some species of fish had a high protein content (19-20 g/100 g sample) and quality (e.g., lysine content = 1,750-1,870 mg/g sample and 93.8- 97.9 mg/g protein). Their protein qualities were endorsed by amino acid score (amino acid score 100). These results suggest that the analyzed aquatic animals have high nutrient quality and are efficient/indispensable food resources for improving the nutritional status of the rural population of the country.

Animal Husbandry
  • Swarmistha Devi ARIBAM, Yumiko MASUKAGAMI, Kazumasa SHIRAIWA, Sayaka N ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 201-205
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Previously, we developed the monoclonal antibody (mAb) 449 after immunizing BALB/c mice with a live attenuated mutant of Salmonella enterica serovar Typhimurium (S. Typhimurium), and it helped protect against S. Typhimurium infection. Although the immunogen specific for mAb449 has been found to be localized in the lipopolysaccharide (LPS) region, it is not clear which part of LPS is involved in the defense against Salmonella infection. The present study aimed to identify sites recognized by mAb449. Electron microscopy analysis showed that mAb449 binds to the surface of Salmonella serotypes that express the O4 antigen, such as serovar Abortusequi and Paratyphi B. In addition, mAb449 enhanced the uptake of only O4-positive Salmonella serotypes within mouse macrophage-like cells. The results demonstrated that mAb449 is specific for the O4 antigen. We further verified the protective potential of mAb449 against O4-positive Salmonella serotypes in mice infection model, and found that mAb449 exhibited protective effect against the O4-positive Salmonella serotypes such as Abortusequi and Paratyphi B.

  • Koji NAKAGAMI
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 207-214
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Grassland managers should consider the mean and variance of herbage mass for appropriate pasture management. Herein, a time and labor saving method to estimate variance in herbage mass was developed through extending an existing simple estimation method for mean mass. Herein, the difference between the highest and lowest masses in a given paddock and the quotient of pasture size by plot size were substituted for the range and sample size in an existing equation relating range to standard deviation (SD). The applicability of the method was evaluated using Monte Carlo simulations representing virtual pastures with a variety of conditions, and field experiments were conducted to confirm the simulation results. There was a clear relation between the ratio of the range to the SD and volume of generated random numbers in the simulation study, and the curve of the existing equation passed very close to the data points. Thus, the SD of herbage mass could be estimated using this equation. Although the accuracy of the estimate, which was expressed as a ratio of the actual variance of the random numbers, varied widely among simulated datasets, the average accuracy of the estimate was high; a similar result was produced under the field experiments that compares the new estimation method to the random sampling method.

  • Satoshi HAGA, Kazuhiro MATOBA, Hiroshi ISHIZAKI, Yasuko TOGAMURA, Yasu ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 215-222
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Grazing cows ingest large quantities of β-carotene (BC) from fresh pasture. The absorbed BC is carried to the mammary glands by the bloodstream and is subsequently transferred to the milk. This study was undertaken to assess the time-course changes in the relationship between serum and milk BC concentrations by calculating the rate of serum and milk BC concentration increase and estimating the mammary transfer of BC efficiency rate in mid-lactation dairy cows following a shift from drylot to time-limited grazing. For the first experiment, dairy cows were allocated to two treatment groups (each n = 3). The experimental grazing durations were 4 h (4hG) or 7 h (7hG) daily for 3 weeks. The serum BC concentration in the 7hG group was higher than that in the 4hG group. Nevertheless, no difference in milk BC concentration was found between the 4hG and 7hG groups. To investigate whether a difference exists in the rate of serum and milk BC increase in cows with time-limited grazing of more than 7 h daily, we conducted a second experiment for which the designated grazing time was 8 h daily for 4 weeks (n = 8). The rate of serum BC increase was greater than that of milk BC during days 14 to 28 of grazing. During the first 3 weeks of grazing, the estimated mammary extraction rate of BC significantly decreased, and the values at days 14 and 21 were significantly lower than those in drylot-feeding cows. These results suggest that the serum BC concentration strongly reflects the daily grazing time; however, the change in milk BC concentration is apparently delayed compared with that in the serum in cows grazing more than 7 h daily, and the relationship between the serum and milk BC concentrations changes following a shift from drylot feeding to time-limited grazing.

Fisheries
  • Yuji TOMARU, Tadashi MATSUBARA, Takayuki MINE, Tomoyuki SHIKATA, Keizo ...
    原稿種別: research-article
    2019 年 53 巻 3 号 p. 223-228
    発行日: 2019/07/01
    公開日: 2019/09/12
    ジャーナル フリー

    Certain marine diatoms can be harmful to seaweed cultivation farms, resulting in loss of yield and quality. Diatoms are exposed to viral attack; to date, more than 20 diatom-infecting viruses have been isolated and characterized to different extents. Nevertheless, no data have been reported on viruses infecting the harmful bloom-forming diatom Asteroplanus karianus, which causes bleaching of cultured Pyropia. In this study, we successfully isolated a novel virus that infects A. karianus from the sediment of the Ariake Sound, which is famous for its nori cultivation. The virion was 21 nm in diameter and exhibited apparent host cell lysis over 10 days post inoculation. Moreover, using degenerate PCR targeting the RNA-dependent RNA polymerase (RdRp) domain, ssRNA virus sequences were detected from a natural diatom bloom population, which included A. karianus, collected in the Ariake Sound. The phylogenetic analysis showed that the detected sequence was monophyletic with diatom-infecting ssRNA virus members at a bootstrap value of 85%. These results indicated that viruses infecting A. karianus are present in the Ariake Sound and may play a role in decreasing the diatom populations in natural environments.

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