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591.
Microbial Biomass and Tolerance of Microbial Community on an Aged Heavy Metal Polluted Floodplain in Japan 总被引:1,自引:0,他引:1
Takafumi Kamitani Hirosuke Oba Nobuhiro Kaneko 《Water, air, and soil pollution》2006,172(1-4):185-200
The objective of the present study was to increase understanding of the effects of heavy metal pollution and soil properties on microorganisms in relation to the biomass and microbial functional community. Soil samples were collected from aged polluted and reference sites on a floodplain. The soil Cu, Zn and Pb total concentrations were much higher at the polluted sites (average 231.6–309.9 mg kg?1, 195.7–233.0 mg kg?1, and 72.4–86.0 mg kg?1, respectively) than at the reference site (average 33.3–44.0 mg kg?1, 76.7–98.0 mg kg?1, and 30.8–41.6 mg kg?1, respectively), while the available heavy metal concentrations in CaCl2 extraction were similar in all sites. Small seasonal variations in the size of microbial biomass were observed. Ambient soil properties (e.g. total C, N, pH, moisture content, and CEC) affected the soil microbial biomass more than the heavy metal pollution. However, the aged pollution tended to impact on the composition of the microbial community. PICT (pollution-induced community tolerance) test using BIOLOG Ecoplates showed enhanced tolerance of the microbial community to Cu stress in the polluted site. In non polluted but low nutrient, low pH and low moisture soil, the microbial biomass was lower and the microbial community was more vulnerable to Cu stress. In spite of the low heavy metal availability due to ageing, the BIOLOG technique provided sensitive detection of microbial community level changes in PICT analysis. 相似文献
592.
Nobuhiro Kaneko Yasunori Sugawara Toshizumi Miyamoto Motohiro Hasegawa Tsutom Hiura 《Pedobiologia》2005,49(6):521-528
Differences in tree species may lead to contrasting soil environments via differences in litter chemical quality and physical environmental factors, such as soil type and soil moisture. However, separating the effects of litter quality and physical environment is difficult under field conditions. Both litter quality and soil environment affect the species composition of the soil animal community. A diversity gradient of canopy tree species (11–25 species) located on homogeneous soil substrate at Tomakomai Experimental Forest of Hokkaido University was used to analyse the relationship between tree species diversity and oribatid mite community structure. Soil samples were collected from three levels of tree species richness (high, intermediate and low) with three replicates each, in July 2000. Leaf area index (LAI) was positively correlated with tree species diversity suggesting higher litter input into the soils with increasing tree diversity. However, the tree species diversity gradient affected neither accumulation of litter on the forest floor nor abundance and species richness of oribatid mites. Canopy and understory plant species richness, LAI, total soil carbon and biomass of epigeic and endogeic earthworms did not significantly affect mite community structure as indicated by redundancy analysis (RDA). The results suggest that oribatid mite community structure is minimally affected by tree species diversity and associated changes in litter diversity. 相似文献
593.
Tomigahara Y Matsui M Matsunaga H Isobe N Kaneko H Nakatsuka I Yoshitake A Yamane S 《Journal of agricultural and food chemistry》1999,47(1):305-312
To examine the metabolic fate of 7-fluoro-6-(3,4,5, 6-tetrahydrophthalimido)-4-(2-propynyl)-2H-1,4-benzoxazin-3( 4H)-one (S-53482), rats were given a single oral dose of [phenyl-(14)C]-S-53482 at 1 (low) or 100 (high) mg/kg. The radiocarbon was almost completely eliminated within 7 days after administration in both groups. (14)C recoveries (expressed as percentages relative to the dosed (14)C) in feces and urine were 56-72 and 31-43%, respectively, for the low dose and 78-85 and 13-23%, respectively, for the high dose. S-53482 and seven metabolites were identified in urine and feces. Six of them were purified by several chromatographic techniques and identified by spectroanalyses (NMR and MS). Alcohol derivatives and an acetoanilide derivative were isolated from urine. Three sulfonic acid conjugates having a sulfonic acid group incorporated into the double bond of the 3,4,5,6-tetrahydrophthalimide moiety were isolated from feces. On the basis of the metabolites identified in this study, the metabolic pathways of S-53482 in rats are proposed. 相似文献
594.
Yuichi Saeki Ai Kaneko Toshiaki Hara Koutaro Suzuki Takeo Yamakawa Minh Thi Nguyen Yoshitaka Nagatomo Shoichiro Akao 《Soil Science and Plant Nutrition》2005,51(7):1043-1052
In order to analyze the phylogeny of soybean-nodulating bacteria in alkaline soils in Vietnam, indigenous soybean-nodulating bacteria were isolated from root nodules by cultivating three kinds of Rj -soybean cultivars on two alkaline soils in Vietnam. The 120 isolates were classified into two major genera of soybean-nodulating rhizobia, namely Bradyrhizobium and Sinorhizobium genera, based on a growth analysis on medium and PCR-RFLP analyses of 16S rDNA and of the 16S–23S rDNA internal transcribed spacer (ITS) region. Most of the isolates of B. japonicum were extra-slow-growing and their ITS types were similar to that of B. japonicum USDA 135. They were not isolated from the soybean cultivar CNS used as Rj2 Rj3 genotype. Isolates of Sinorhizobium were divided into two groups, S. fredii and S. sp., based on a PCR-RFLP analysis of 16S rDNA. Furthermore, PCR-RFLP analysis of the 16S–23S rDNA ITS region enabled to separate them into five types, three ITS types associated with S. fredii and two with S. sp. Sinorhizobium was frequently isolated from the three soybean cultivars on two soils. From the isolate ratio, it was suggested that B. japonicum strains similar to B. japonicum USDA 135 and S. fredii predominated in the alkaline soils of Vietnam. Additionally, our findings indicated that the Rj -genotypes affected not only the compatibility, but also the preference for nodulation between the host soybean and rhizobia. 相似文献
595.
596.
Kenji Fujino Mari Obara Hitoshi Kiuchi Hiroshi Shinada Tsutomu Nishimura Toshihiko Maekawa Yuji Hirayama 《Plant Breeding》2020,139(5):845-852
A series of DNA markers for various agronomic traits may accelerate the success of marker-assisted selection in practical plant breeding programmes. Here, we developed DNA markers for the blast resistance gene Pi-cd. In this study, we examined the effects of the Pi-cd locus on not only blast resistance but also agronomic traits in agriculture. We developed three pyramiding lines (PLs) coupling Pi-cd with three blast resistance genes, pi21, Pi35 and Pi39. The effect of Pi-cd on blast resistance was dependent on the coupled resistance genes. Then, we evaluated the effects of Pi-cd on 13 agronomic traits. Amylose content and 1,000-grain weight showed significant differences between the PLs and current commercial varieties, which had no negative effects on agronomic trait values. Furthermore, we investigated the distribution of genotype for the Pi-cd locus among varieties of upland rice. The KT genotype specific to rice blast resistance may be predominant in the varieties. The results suggested that Pi-cd has the potential to be useful for improving blast resistance in rice breeding programmes. 相似文献
597.
Eishiro Okamoto Hitoshi Kasahara Akira Chiba Masayuki Taniguchi Eiichi Saitoh 《Fisheries Science》2009,75(2):463-471
We have discovered multiple acidic cysteine protease inhibitors, in addition to the known Eel-CPI-1, in the skin mucus extract
of the Japanese eel Anguilla japonica by using the two-dimensional gel system of gelatin reverse zymography. Two of the acidic inhibitors, which we have named
Eel-CPI-2 and Eel-CPI-3, were purified to homogeneity by anion exchange chromatography on a column of DEAE-Sepharose CL-6B,
followed by fast protein liquid chromatography on Superdex 75 10/300 GL and HiTrap Q HP columns. The amino acid compositions
of Eel-CPI-2 and Eel-CPI-3 were found to be almost identical and closely similar to that of the eel galectin AJL1. The molecular
masses of Eel-CPI-2 and Eel-CPI-3 were elucidated to be 16,089.080 and 16,089.137 Da, respectively, by matrix-assisted laser
desorption/ionization time-of-flight mass spectrometry. The apparent dissociation constant of Eel-CPI-2 and Eel-CPI-3 for
cysteine protease papain was determined to be 1.79 × 10−7 and 1.05 × 10−7 M, respectively, by a quartz crystal microbalance technique. 相似文献
598.
Tamura H Fujita A Steinhaus M Takahisa E Watanabe H Schieberle P 《Journal of agricultural and food chemistry》2011,59(18):10211-10218
Eleven odor-active thiols, namely, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, 2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-mercapto-3-pentanone, 4-mercapto-3-hexanone, 3-mercapto-3-methylbutyl formate, and 2-methyl-3-thiophenethiol, recently identified in an extract prepared from white sesame seeds, were quantitated in sesame using stable isotope dilution analyses. For that purpose, the following deuterium-labeled compounds were synthesized and used as internal standards in the quantitation assays: [2H6]-2-methyl-1-propene-1-thiol, [2H3]-(E)- and [2H3]-(Z)-2-methyl-1-butene-1-thiol, [2H3]-2-methyl-3-furanthiol, [2H2]-3-mercapto-2-pentanone, [2H3]-4-mercapto-3-hexanone, [2H6]-3-mercapto-3-methylbutyl formate, and [2H3]-2-methyl-3-thiophenethiol. On the basis of the results obtained, odor activity values (OAVs) were calculated as ratio of the concentration and odor threshold of the individual compounds in cooking oil. According to their high OAVs, particularly the 3-methyl-1-butene-1-thiols (OAV: 2400) and the 2-methyl-1-butene-1-thiols (OAV: 960) were identified as the most odor-active compounds in pan-roasted white sesame seeds. These compounds were therefore suggested to be mainly responsible for the characteristic but rather unstable sulfury aroma of freshly pan-roasted white sesame seeds. 相似文献
599.
Pathipan Sutigoolabud Keishi Senoo Somchai Ongprasert Takafumi Mizuno Takashi Mishima Makoto Hisamatsu Hitoshi Obata 《Soil Science and Plant Nutrition》2005,51(4):583-588
Potassium chlorate is widely used as an active substance for flower induction in longan plantation fields for off-season production of longan fruits in northern Thailand. Contamination of groundwater with residual chlorate in soil is a cause for concern because of its toxicity to human health. Based on our previous finding that the addition of glucose or sucrose to soil was effective for accelerating the disappearance of residual chlorate in soil, the effect of the addition of molasses, which contains a high concentration of sucrose, as a substitute for glucose or sucrose was examined in laboratory and pot experiments. Under laboratory conditions, the addition of molasses to soil at the concentrations of 100 to 200 g kg−1 soil strikingly enhanced the rate of disappearance of chlorate applied at 341 mg kg−1 soil. Addition of diluted molasses was also effective for the accelerated disappearance of chlorate in soil when 33 g kg−1 soil of molasses was added repeatedly. The effect of repeated addition of diluted molasses to soil on the decontamination of residual chlorate in soil was also confirmed in an outdoor pot experiment. These results may lead to the development of a practical method of cleaning-up chlorate-polluted soil in longan plantation fields. 相似文献
600.
Kazuya Koizumi Nobuhiro Kuboyama Kohtaro Tomono Akira Tanaka Aiko Ohki Hitoshi Kohno Ko Wakabayashi Peter Bger 《Pest management science》1999,55(6):642-645
New fluoroalkyl-substituted 1,3,5-triazine derivatives were synthesized and screened for herbicidal activity using a greenhouse pot test. Surprisingly, a series of 2-alkyl-4-fluoroalkyl-6-aralkylamino-1,3,5-triazines e.g. 6-(4-bromobenzylamino)-2-methyl-4-trifluoromethyl-1,3,5-triazine was found to possess strong pre- and post-emergence herbicidal activities, although the conventional herbicidal 1,3,5-triazines generally should have a 2-substituted-4,6-diamino-1,3,5-triazine structure for herbicidal activity. Our compounds show strong Photosynthetic Electron Transport inhibitory activity (PI50 c 7). Although their herbicidal effect is considered to be caused by a process similar to that for the conventional 1,3,5-triazine herbicide atrazine, they can control atrazine-resistant Chenopodium album effectively, and will thus form promising trial compounds for new triazine herbicide design. 相似文献