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81.
转5-烯醇式丙酮酰莽草酸-3-磷酸合酶(EPSPS)基因抗草甘膦烟草和棉花的获得 总被引:12,自引:0,他引:12
以从抗草甘膦的荧光假单胞菌(Pseudomonas fluorescens)G2中克隆的、并按双子叶植物偏爱密码子改造的5-烯醇式丙酮酰莽草酸-3-磷酸合酶(EPSPS)基因aroAG2M为目的基因,用菊花Rubisco小亚基的启动子驱动,在基因的5'端加叶绿体定位信号肽,构建植物表达载体。用根癌农杆菌(Agrobacterium tumefaciens)介导的叶盘法转化烟草(Nicotiana tabacum)获得转基因植株,PCR检测表明,外源基因已整合到烟草基因组中。转基因和非转基因植株6~8叶龄苗的叶片涂抹不同浓度的草甘膦异丙胺盐,表明转基因植株可抗4‰浓度的草甘膦,而非转基因对照植株则在2‰草甘膦时即死亡。花粉管通道法转化棉花(Gossypium hirsutum),得到3株具有草甘膦抗性的转基因植株,PCR和Southern检测显示,外源基因已整合到棉花基因组中,田间喷洒草甘膦异丙胺盐水剂,表明T1代转基因植株具有草甘膦抗性。 相似文献
82.
Kura clover (Trifolium ambiguum M.B.) is a perennial rhizomatous forage legume whose use is currently limited by difficulties in its establishment in part attributable to nodulation problems and very specific rhizobial requirements. A limited number of Kura clover-nodulating rhizobial strains are currently available and many have a limited effectiveness. In this study, 128 rhizobia were isolated from four sites in the center of origin of Kura clover (i.e., two in Azerbaijan, one in Armenia, and one in Northwest Iran) using the three ploidy levels of Kura clover (diploid, tetraploid, and hexaploid), red clover (Trifolium pratense L.), and white clover (Trifolium repens L.) plants as trap hosts. Rhizobia were fingerprinted using repetitive extragenic palindromic polymerase chain reaction (BOXA1R primer) and their genetic diversity was measured using the Shannon-Weaver diversity index. The nodulation specificity and phenotypic diversity of a subset of 13 isolates was determined. Genetic diversity among the 128 isolates was large and similar for rhizobia grouped according to their geographic origin or original host plant. Phenotypic diversity was significant; percentage of similarity among 13 isolates ranging between 38 and 92%. Nodulation specificity of the Kura clover-nodulating rhizobial isolates studied was less complex and not as clearly delineated as previously reported. Some strains originally isolated from Kura clover could effectively nodulate more than one ploidy level of Kura clover and even one or both of two other Trifolium species (i.e., red clover and white clover). Three strains formed effective nodules on both Kura clover and white clover; however, none promoted plant growth of both species to levels currently obtained with commercial inoculants when evaluated in a growth chamber. Rhizobial isolates that are highly effective with both species have yet to be identified. 相似文献
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85.
《Land Degradation \u0026amp; Development》2017,28(3):994-1004
Soil erosion is a key process to understand the land degradation, and modelling of soil erosion will help to understand the process and to foresee its impacts. The applicability of the Universal Soil Loss Equation (USLE) at event scale is affected by the fact that USLE rainfall erosivity factor does not take into account runoff explicitly. USLE‐M and USLE‐MM, including the effect of runoff in the event rainfall–runoff erosivity factor, are characterized by a better capacity to predict event soil loss. The specific objectives of this paper were (i) to determine the suitable parameterization of USLE, USLE‐M and USLE‐MM by using the dataseries of Sparacia experimental site and (ii) to evaluate their performances at both event and annual scale. The measurements allowed to establish the relationships for calculating the factors of USLE, USLE‐M and USLE‐MM usable at the Sparacia experimental area. At first, for slope‐length values greater than 33 m, the calibration of USLE model at event scale pointed out that sediment delivery processes, that is processes involving deposition of the transported eroded soil particles, occur. The analysis showed that USLE and USLE‐M tend to overestimate low event soil losses, while for USLE‐MM, this tendency is less pronounced. However, the USLE‐MM performed better than USLE and USLE‐M and was able to reproduce better than other two models the highest soil loss values that are the most interesting from a practical point of view. The results obtained at annual scale were generally consistent with those obtained at event scale. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
86.
倪保志 《山东省农业管理干部学院学报》2002,(1)
2 0世纪 70年代初出现了打开中美两国关系的历史性机会。毛泽东审时度势 ,在中美关系问题上作出了具有转折意义的重大战略决策 ,同美国有远见的政治家尼克松一道打开了封闭已久的中美关系大门。从国家利益出发 ,超越意识形态制定对外政策是中美关系得以正常化的关键。 相似文献
87.
水稻辐射育种早期选择方法的研究 总被引:1,自引:0,他引:1
本试验利用放射线辐照水稻种子,进行诱变育种,探索辐射育种的M_1代选择方法。在原有工作的基础上,提出了M_1代单株综合性状好、结实率高为选择标准。几年的试验,均在受试材料的M_1代中获得符合际准的单株,并从中选育出新品种——“辐415”已用于水稻生产。 相似文献
88.
Finn Saxegaard 《Acta veterinaria Scandinavica》1981,22(2):153
One hundred and two Mycobacterium avium and M. avium-like strains isolated from domestic and wild animals were submitted to serological typing by means of the agglutination method developed by Schaefer. Of the 82 porcine strains M. intracellulare serotype 8 dominated, followed in order of frequency by serotypes 1, 4, 2, 10 and 6. Of the 20 strains originating from other animals 7 were typed as either serotype 2, 3, 8 or 10. The 3 strains isolated from wild birds were all serotype 2. As a considerable number of the wild animal strains were autoagglutinable, the suitability of the agglutination test for typing such strains is discussed. 相似文献
89.
Davis DG Schaefer DM Hinchcliff KW Wellman ML Willet VE Fletcher JM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):93-96
Hypogammaglobulinemia as a result of failure of transfer of passive immunity (FTPI) is an important risk factor for infectious disease in neonatal foals. The current gold standard for determining serum immunoglobulin concentrations is radial immunodiffusion (RID). The purpose of this study was to compare immunoglobulin concentrations measured by RID with those determined by an automated turbidimetric immunoassay (TIA), which has a much shorter turnaround time. Immunoglobulin concentrations were measured by both RID and TIA in serum collected from 84 neonatal foals. Sixty-seven foals had results within the linear range for both assays. Sensitivity and specificity of TIA for diagnosis of FTPI with IgG < or = 800 mg/dL were 0.81 (95% CI 0.70-0.88) and 0.86 (95% CI 0.76-0.93) and with IgG < or = 400 mg/dL were 0.63 (95% CI 0.35-0.86) and 0.92 (95% CI 0.87-0.95), respectively. A significant linear relationship was found between IgG concentrations determined by TIA and RID (TIA = 0.9511RID + 8.4354; R2 = .59, P < .0001). The coefficients of variation for between-run and within-run precision for the TIA were 2.5 and 3%, respectively. Storage of samples from 10 foals at -20 degrees C for 10-12 months resulted in a reduction in TIA-measured serum IgG concentration of -17.6% (SD = 3.7%), indicating that long-term storage of samples at -20 degrees C should be avoided. The results of this study indicate that measurement of serum IgG by TIA can be used to evaluate foals for FTPI. 相似文献
90.
In order to develop a specific tool differentiating the African field strains of Mycoplasma mycoides subsp. mycoides SC from other potentially less virulent strains, including the vaccine strains, we have developed a PCR followed by a restriction enzyme analysis (PCR–REA). This approach also differentiates the African field strains from the Australian strains and the type strain PG1. The genomic marker detected by the PCR–REA is based on a single nucleotide change in the bgl gene that codes for 6-phospho-β-glucosidase (Bgl), an enzyme that is involved in sugar metabolism. 相似文献