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41.
Radioisotope techniques are well known as methods for evaluating symplastic ion absorption in roots. In the present study, a new method for evaluating symplastic cadmium (Cd) absorption in plant roots was developed using the enriched isotopes 113Cd and 114Cd. Seedlings of Solanum melongena were exposed to an enriched isotope solution of 113Cd at 25°C for 30 min. The roots were excised from each seedling and were then immersed in a cold buffer solution without Cd at 2°C for 120 min to suppress the metabolic activity of the roots. Finally, the roots were treated with a cold buffer solution containing enriched stable isotope 114Cd at 2°C for 120 min, whereby the apoplastically bound 113Cd was desorbed. We tested the validity of our method for evaluating symplastic Cd in roots compared with the conventional method based on differences in the amount of Cd absorbed at 2°C and 25°C using unlabeled Cd. There was no difference in the symplastic Cd content of the roots between the two methods. These results indicate that it is possible to evaluate the symplastic Cd content in roots using the enriched isotopes 113Cd and 114Cd.  相似文献   
42.
43.
A loop-mediated isothermal amplification (LAMP) reaction with a primer set designed from the rDNA ITS sequence of P. aphanidermatum was developed. Results of a specificity test using 57 strains of Pythium spp. indicated that the LAMP assay gave no cross reactions in other 39 Pythium species, 11 strains of Phytophthora spp. and eight other soil borne pathogens. The detection limit was 10 fg of genomic DNA, which was ten times the sensitivity of the polymerase chain reaction. The LAMP assay was applied to hydroponic solution samples from tomato fields, and the results were compared to those of the conventional plating method. LAMP was observed to be effective for the specific detection of P. aphanidermatum. Furthermore, P. aphanidermatum was detected directly in tomato roots infected with P. aphanidermatum without DNA extraction. The LAMP method established in this study is a simple, sensitive and rapid tool for the detection of P. aphanidermatum.  相似文献   
44.
Stem canker and severe wilt were observed on delphinium plants (Delphinium elatum) in Aomori Prefecture, Japan, in 2008. The fungus isolated from the diseased crown was identified as Fusarium oxysporum f. sp. delphinii on the basis of morphological characteristics, nucleotide sequences, and host range. The isolate induced similar stem canker and wilt symptoms in inoculated delphinium plants. We propose the name “stem canker and wilt” for the disease.  相似文献   
45.
Schoenoplectus juncoides, a noxious weed for paddy rice, is known to become resistant to sulfonylurea (SU) herbicides by a target-site mutation in either of the two acetolactate synthase (ALS) genes (ALS1 and ALS2). SU-resistant S. juncoides plants having an Asp376Glu mutation in ALS2 were found from a paddy rice field in Japan, but their resistance profile has not been quantitatively investigated. In this study, dose–response of the SU-resistant accession was compared with that of a SU-susceptible accession at in vivo whole-plant level as well as at in vitro enzymatic level.  相似文献   
46.
DNA methylation is an important factor for the regulation of gene expression in early embryos. It is well known that the satellite I sequence is more heavily methylated in bovine somatic cell nuclear transfer (NT-SC) embryos than in embryos derived from in vitro fertilization (IVF). However, the methylation status of bovine embryos obtained by other procedures is not well known. To clarify DNA methylation levels of bovine embryos obtained from various procedures, we examined satellite I sequences in bovine blastocyst (BC) embryos derived from NT-SC, NT using embryonic blastomeres (NT-EM), in vivo (Vivo), IVF and parthenogenetic treatment (PA). Furthermore, in order to evaluate the efficacy of DNA demethylation by the NT procedure, we determined the DNA methylation levels in bovine embryos in which NT was recapitulated (Re-NT). Although the DNA methylation levels in the NT-SC embryos were higher than those in the other embryos, the NT-EM embryos exhibited lower DNA methylation levels. The satellite I sequence in the NT-SC embryos was more demethylated than that in the donor cells. Although the DNA methylation level in the individual NT-SC embryos showed variation, the full-term developmental efficacy of these embryos were not different. These findings suggest that the methylation level of the satellite I sequence at the BC stage is not related to the abnormalities of bovine embryos produced by NT-SC. There was no difference in methylation levels between Re-NT and NT-SC embryos. Our results indicated that the DNA methylation status differed among embryos produced by various methods and that at least some of the demethylation of the donor cell genome occurred in the recipient cytoplast after NT-SC, but the demethylation ability of the NT procedure was noted in the first NT but not in the second NT.  相似文献   
47.
Characterization of CTLA-4, PD-1 and PDL-1 genes from swamp and riverine type water buffaloes was done by molecular cloning, sequencing and phylogenetic analysis. The cloned cDNA of CTLA-4, PD-1 and PDL-1 contained an open reading frame of 666, 849 and 870 nucleotides, encoding a polypeptide of 221, 282 and 298 amino acids, respectively. Nucleotide sequence homology of both CTLA-4 and PDL-1 had 99.8% in swamp and riverine type, which gives the identical polypeptide. Meanwhile, PD-1 genes of swamp and riverine type water buffaloes had 99.2% of homology in nucleotide sequence, which has substitution of two amino acid residues. The hexapeptide motif, phosphatidylinositol 3′-kinase and potential glycosylation sites were conserved within the tribe Bovinae. Phylogenetic analysis confirmed the degree of relationship between the bubaline species and justify the distinctness of each breeds by the bootstrap value generated.  相似文献   
48.
The tick-borne pathogen, Anaplasma phagocytophilum (A. phagocytophilum), the causative agent of human granulocytic anaplasmosis (HGA), is increasingly becoming a public health concern as an aetiological agent for emerging infectious disease. We found A. phagocytophilum infection in a pooled sample of field-collected Ixodes persulcatus (I. persulcatus) ticks from one district in Hokkaido, Japan. Thus, to further investigate the prevalence in field-collected ticks, we used PCR assays targeting the A. phagocytophilum gene encoding 44 kDa major outer membrane protein (p44) for screening of I. persulcatus ticks and samples from cattle from pastures. Out of the 281 I. persulcatus ticks, 20 (7.1%) were found to harbor A. phagocytophilum DNA. The infection rate for A. phagocytophilum in cattle was 3.4% (42/1251). In future studies, it will be necessary to investigate effects of the infection in order to understand its pathogenesis of A. phagocytophilum in domestic animals.  相似文献   
49.
It is considered that transformation of iron compounds owing to alternation of submergence and drainage exert a complicated influence on physico-chemical properties of paddy soils and that subsequent changes in physicochemical properties play an important role in the development of paddy soil profile, for example gley formation, occurrence of iron mottling etc. Ferrous iron in waterlogged condition, however, exists in many complex forms, and is under physico-chemical equilibrium in conjunction with the environmental soil condition. In the previous paper, the authors have suggested that ferrous iron status in submerged condition is closely related to the characteristics of genetic soil types from their experiment on fractionation of inorganic ferrous iron (8).  相似文献   
50.
Abstract

Green manure legumes are often used to compare biomass production as well as nitrogen-fixing capacity. Mineral deficiency often limits the symbiotic nitrogen fixation of many legumes, thus limiting their productivity despite their high yielding potential (O’Hara et al. 1988; Flis et al. 1993). Leguminous species require large amounts of P for growth, nodulation, and nitrogen fixation. Consequently, they are often unable to grow in acid soils with low available P. The low P availability in tropical acid soils often arises from fixation of P by Al and Fe in soil. Generally, Al and Fe-phosphates are relatively unavailable to plants (McLachlan 1976; Ae et al. 1990).  相似文献   
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