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61.
Takashi Sato Yoshihiro Kaneta Noritoshi Furuta Hitomi Kobayashi Hayato Shindo Takeshi Ota 《Soil Science and Plant Nutrition》2013,59(5):695-702
We studied the effect of the soil physical properties on soybean nodulation and N2 fixation in the heavy soil of an upland field (UF) and an upland field converted from a paddy field (UCPF) in the Hachirougata polder, Japan. Seeds of the soybean cultivar Ryuho were sown in each field with or without inoculation of Bradyrhizobium japonicum A1017. The soybean plants were sampled at 35 (V3) and 65 (Rl) d after sowing (DAS), and then nodulation and the percentage of N derived from N2 fixation in the xylem sap were determined. The soil physical properties were different between UF and UCPF, especially the air permeability and soil water regime. Nodule growth was restricted in UCPF irrespective of rhizobial inoculation, though rhizobial infection was not inhibited by the unfavorable soil physical conditions. Soybean plant growth was closely related to the nodule mass and N2 fixation activity, and the inoculation of a superior rhizobium strain was effective only at 35 DAS. These results indicate that soybean nodulation and N2 fixation was considerably affected by the physical properties of heavy soil, and that it is important to maintain the N2 fixation activity and inoculate the soybean plants with a superior rhizobium strain at a later growth stage in order to increase soybean production in heavy soil fields. 相似文献
62.
Atsushi Watanabe Yoshihiro Takebayashi Toshiro Ohtsubo Mutsuhisa Furukawa 《Pest management science》2009,65(11):1233-1240
BACKGROUND: Controlled‐release systems using polymer membranes are very important in agriculture for labour‐saving and effective delivery of pesticides and other agents. Polymer‐coated granules are one of the most useful formulations, and a study of the factors for polymer design is necessary to achieve various release patterns. A permeation study using plain membranes was carried out in order to clarify parameters, and the results were compared with the release from polymer‐coated granules. RESULTS: The permeation coefficient of urea through a plain polyurethane membrane decreased significantly as the urethane and alkyl side chain content increased. The glass transition temperature and crosslink density of the polyurethanes hardly influenced its permeability. The release rate from polyurethane‐coated granules was also reduced by alkyl side chains. However, it was faster than that through a plain membrane because of capsule expansion by continuous water penetration and structural changes in the membrane. CONCLUSION: The release rate of urea through a polyurethane plain membrane and from polyurethane‐coated granules can be controlled by changing the chemical properties of the membrane. In addition, physical properties such as the glass transition temperature Tg or crosslink density should be considered to assess the release profile from polyurethane‐coated granules. Copyright © 2009 Society of Chemical Industry 相似文献
63.
Takayoshi Miyabayashi BVS MS PhD Mark Smith BS RT MS † Yoshihiro Tsuruno BVSc 《Veterinary radiology & ultrasound》2000,41(4):308-312
Various magnetic resonance (MR) imaging techniques have been used to assess lumbar spinal abnormalities in people. Four, young adult, clinically normal dogs were used to compare images of the spinal cord acquired using conventional spin-echo and rapid acquisition relaxation-enhanced (RARE), commonly called fast spin-echo (FSE), magnetic resonance imaging techniques. Lateral myelograms were made as an anatomic control. The T2-weighted FSE technique was characterized by better image quality than the T2-weighted conventional spin-echo technique. The short acquisition time with the FSE technique allowed increases in the matrix size and number of excitations, thus improving resolution and signal-to-noise ratio. In canine lumbar spinal MR imaging, use of a FSE technique is recommended to reduce the overall time for imaging and to improve image quality. 相似文献
64.
65.
Yohsuke OGAWA Masahiro EGUCHI Yoshihiro SHIMOJI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(4):538
Akabane virus (AKAV), belonging to the genus Orthobunyavirus and family Peribunyaviridae, causes reproductive and congenital abnormalities in ruminants. Its envelope glycoprotein Gc is a neutralizing antigen, on which at least five distinct antigenic regions have been identified. We attempted to identify the domains using truncated recombinant AKAV Gc proteins expressed in Escherichia coli and monoclonal antibodies (mAbs) with AKAV-neutralizing activity. Dot blot analysis revealed that amino acid positions 1–97 and 189–397 (Gc1–97 and Gc189–397) in the truncated recombinant proteins reacted with the mAbs. Additionally, AKAV was neutralized by sera from mice immunized with these recombinant proteins. The results suggested that the two domains contain neutralizing epitopes and could be potential subunit vaccines against AKAV. 相似文献
66.
Tetsuo Tamura Kazunori Inoue Hideto Nishiki Masafumi Sakata Makoto Seki Teruaki Koga Yoshihiro Ookubo Kazuhiro Akutsu Say Sato Kouichi Saitou Hikari Shinohara Terumi Kuraisi Hiroshi Kajikawa Mitsunori Kurihara 《Animal Science Journal》2019,90(1):62-70
We evaluated the influence on milk production of feeding early lactation cows a diet that included 14.5% crude protein (CP) and that did not meet methionine (Met) requirements or that met them by supplying rumen‐protected Met (RPMet). Thirty‐nine multiparous Holstein cows were allocated into two groups. For 15 weeks after calving, each group was fed one of the two total mixed rations, Control (n = 20) or Treatment (n = 19). The Treatment group received added RPMet at 0.034% (8 g/day) of the Control diet on dry matter basis. The adequacies of Met for the Control and Treatment groups were 96% and 106%, respectively, and for other amino acids, >110%. The CP level (14.5%) was 1 percentage point lower than that recommended by the Japanese Feeding Standard (2006). No between‐group differences were found in milk yield (40 kg/day), milk composition, plasma profile, rumen fermentation, nitrogen balance, or cow health. Met intake and the amount of rumen‐undegradable feed Met were higher in the Treatment group (p < 0.05). Microbial Met and total metabolizable Met did not differ between groups. Supplying RPMet in a 14.5% CP diet during early lactation did not dramatically affect milk production, because the amount of total metabolizable Met was unchanged. 相似文献
67.
Occurrence of New Powdery Mildew on Greenhouse Tomato Cultivars 总被引:2,自引:0,他引:2
Yoshinori MATSUDA Koichi KASHIMOTO Yoshihiro TAKIKAWA Rika AIKAMI Teruo NONOMURA Hideyoshi TOYODA 《Journal of General Plant Pathology》2001,67(4):294-298
During a year-round survey on the occurrence of powdery mildew on greenhouse-cultivated tomato plants, the disease was most
severe in June and July. All tomato plants (45 commercial cultivars and 11 breeding lines) tested were infected with the pathogen
but had different degrees of susceptibility. The pathogen was epiphytic and produced white, round pustules mainly on leaves
of tomato plants. The pathogen produced conidia singly on conidiophores and forked appressoria on inoculated tomato leaves
and seemed to be an Oidium sp. of Erysiphe polygoni type.
Received 18 December 2000/ Accepted in revised form 22 July 2001 相似文献
68.
Yuri ABE Tomokazu TAMURA Shiho TORII Shiho WAKAMORI Makoto NAGAI Kazuya MITSUHASHI Junki MINE Yuri FUJIMOTO Naofumi NAGASHIMA Fumi YOSHINO Yukihiko SUGITA Takushi NOMURA Masatoshi OKAMATSU Hiroshi KIDA Yoshihiro SAKODA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):61-70
In our previous study, we genetically analyzed bovine viral diarrhea viruses (BVDVs)
isolated from 2000 to 2006 in Japan and reported that subgenotype 1b viruses were
predominant. In the present study, 766 BVDVs isolated from 2006 to 2014 in Hokkaido,
Japan, were genetically analyzed to understand recent epidemics. Phylogenetic analysis
based on nucleotide sequences of the 5′-untranslated region of viral genome revealed that
766 isolates were classified as genotype 1 (BVDV-1; 544 isolates) and genotype 2 (BVDV-2;
222). BVDV-1 isolates were further divided into BVDV-1a (93), 1b (371) and 1c (80)
subgenotypes, and all BVDV-2 isolates were grouped into BVDV-2a subgenotype (222). Further
comparative analysis was performed with BVDV-1a, 1b and 2a viruses isolated from 2001 to
2014. Phylogenetic analysis based on nucleotide sequences of the viral glycoprotein E2
gene, a major target of neutralizing antibodies, revealed that BVDV-1a, 1b and 2a isolates
were further classified into several clusters. Cross-neutralization tests showed that
BVDV-1b isolates were antigenically different from BVDV-1a isolates, and almost BVDV-1a,
1b and 2a isolates were antigenically similar among each subgenotype and each E2 cluster.
Taken together, BVDV-1b viruses are still predominant, and BVDV-2a viruses have increased
recently in Hokkaido, Japan. Field isolates of BVDV-1a, 1b and 2a show genetic diversity
on the E2 gene with antigenic conservation among each subgenotype during the last 14
years. 相似文献
69.
Yoshihiro Katayama Yoko Mashino Nobuyuki Nishikubo Kaori Yoshitomi Ryo Funada Shinya Kajita 《Journal of Wood Science》2002,48(6):457-466
We have investigated the spatial regulation of the accumulation of enzymes involved in the biosynthesis of shikimate and lignin during differentiation of primary xylem from the apical meristem via procambium in hybrid aspen (Populus sieboldii x Populus grandidentata). Immuohistochemical staining revealed that, in the top part of shoots, lignification began in a single or just a few adjacent vessel elements and subsequently spread to neighboring cells. The spatial localization of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS), which is one of the key enzymes in the shikimate pathway, was tightly correlated with the cell-specific deposition of lignin in the primary xylem. We also found that the spatial localization of enzymes in the general phenylpropanoid pathway and in the lignin-specific pathway was closely associated with the cell-specific deposition of lignin and the accumulation of DAHPS. Our data suggest that enzymes that act in the shikimate, general phenylpropanoid, and lignin-specific pathways are initially produced and function coordinately in a single or a few adjacent elements at the start of primary xylem development. 相似文献
70.
To characterize the mechanism of the reaction of lignin with aqueous acetic acid (AW) containing a small amount of H2SO4, guaiacylglycerol--guaiacyl ether (GOG), and guaiacylglycerol--syringol ether (GOS) were refluxed in 90% AW with 0.28% H2SO4 for 0–120 min. Reaction products and their silylated derivatives were characterized by analytical methods such as gas chromatography-mass spectrometry and nuclear magnetic resonance. When the model compounds were allowed to react at boiling temperature for 0 min (heat-up time 30 min), most of their primary alcohol groups and some of their secondary alcohol groups were acetylated, but their phenolic groups were not. About 90% of GOG was degraded, polymerized, or both during boiling for at least 15 min, yielding guaiacol and isocoumaran compounds (GOG-e and GOG-f) in addition to homovanillin (II) as guaiacylvinyl alcohol (I) and other minor products. GOS yielded syringol, homovanillin (II), and a novel compound (V) together with unknown products but not the corresponding isocoumaran compounds. 相似文献