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河北省不同地区棉蚜对吡虫啉等杀虫剂抗药性发展动态研究 总被引:6,自引:1,他引:5
2004—2007年间,测定了氧化乐果、灭多威、吡虫啉和啶虫脒等杀虫剂对河北省不同地区棉蚜的毒力。与敏感基线比较,河北省各地棉蚜对灭多威的抗药性始终处于中、高抗水平,抗性倍数最高达94.04倍;对氧化乐果的抗药性发展较快,但基本仍处于中、低抗水平,其抗性倍数为2.15~20.76;河北省各地棉蚜种群对新烟碱类杀虫剂吡虫啉和啶虫脒的抗药性差异波动较大,对啶虫脒的差异最大可达25.83倍。 相似文献
144.
Interactions between phosphorus availability and microbes in a wheat–maize double cropping system: A reduced fertilization scheme 下载免费PDF全文
YU Xiao-jing CHEN Qi SHI Wen-cong GAO Zheng SUN Xiao DONG Jing-jing LI Juan WANG Heng-tao GAO Jian-guo LIU Zhi-guang ZHANG Min 《农业科学学报》2022,21(3):840-854
Mechanisms controlling phosphorus(P) availability and the roles of microorganisms in the efficient utilization of soil P in the wheat–maize double cropping system are poorly understood. In the present study, we conducted a pot experiment for four consecutive wheat–maize seasons(2016–2018) using calcareous soils with high(30.36 mg kg–1) and low(9.78 mg kg–1) initial Olsen-P content to evaluate the effects of conventional P fertilizer application to both wheat and maize(Pwm) ... 相似文献
145.
The peroxisomal matrix shuttling receptor Pex5 plays a role in FB1 production and virulence in Fusarium verticillioides 下载免费PDF全文
YU Wen-ying LIN Mei YAN Hui-juan WANG Jia-jia ZHANG Sheng-min LU Guo-dong WANG Zong-hua Won-Bo SHIM 《农业科学学报》2022,21(10):2957-2972
The peroxisomal matrix oxidase,catalase and peroxidase are imported peroxisomes through the shuttling receptors,which regulates the cellular oxidative homeostasis and function.Here,we report that PTS1 shuttling receptor FvPex5 is involved in the localization of PTS1,utilization of carbon sources and lipids,elimination ROS,cell wall stress,conidiation,fumonisin B1(FB1) production,and virulence in maize pathogen Fusarium verticillioides.Significantly,differential expression o... 相似文献
146.
Proteomic analysis of pathogen-responsive proteins from maize stem apoplast triggered by Fusarium verticillioides 下载免费PDF全文
During the attack of a pathogen, a variety of defense-associated proteins are released by the host plant in the apoplast to impede the perceived attack. This study utilized the mass spectrometry(LC-MS/MS) and label-free quantification method to analyze the apoplastic fluid(APF) from maize stalk and identified the proteins responsive to the Fusarium verticillioides infection. We have identified 742 proteins, and among these, 119 proteins were differentially accumulated(DAPs), i.e., 35 up-regulate... 相似文献
147.
FENG Yu GUO Chang-jiang WEI Jing-yu YANG Ji-jun GE Yu-zhang GAO Lan-xing 《园艺学报》2000,16(12):1313-1316
AIM: To investigate the effects of exogenous L-carnitine on lipid metabolism in semi-starved rats fed on high fat diet. METHODS: The semi-starved rats were restricted half in calorie intake on high fat diet for 2 week. L-carnitine was supplied at dose of 250 mg/kg·bw. The changes of plasma carnitine concentration, urinary excretion of ketone body, serum lipase activity, muscle carnitine palmitoyl transferase activity, triglyceride secretion and clearance rate were measured. RESULTS: The results showed that the concentration of plasma free carnitine increased significantly in carnitine supplemented rats compared to normal and semi-starved rats.The activities of muscle carnitine palmitoyltransferase and serum lipase were significantly enhanced in carnitine supplemented rats. The triglyceride secretion rate (TGSR) was also improved remarkably by carnitine supplementation. Meanwhile, the urinary excretion of ketone body was reduced significantly in carnitine supplemented rats compared to semi-starved rats. CONCLUSION: It is concluded that carnitine supplementation can significantly increase the plasma concentration of free carnitine and accelerate the lipid metabolism in semi-starved rats fed on high fat diet. 相似文献
148.
AIM and METHODS: The ratio of mitochondrial DNA (mtDNA) deletion was measured to find the relationship between mtDNA deletion and aged learning and memory deficit. The aged rats were divided into two groups, aged learning and memory deficit group and aged learning and memory normal group. The ratio of mtDNA deletion was measured by dilution polymerase chain reaction. RESULTS: There are deleted mtDNA (about 4834 bp) in the cerebral cortex, hippocampus and cerebellum of both young and aged rats. The ratios of deleted mtDNA were similar in the cerebral cortex,hippocampus and cerebellum of young rats (about 0.00018%). The ratio mtDNA of aged learning and memory normal rats had increased by five-fold in the cerebral cortex and hippocampus, or one-fold in the cerebellum over young rats. The ratio of aged learning and memory dificit rats had increased by one-fold in the cerebral cortex or 0.8-fold in the hippocampus or two-fold in the cerebellum over aged learning and memory normal rats.CONCLUSIONS: There was really the increase of mtDNA in aging rat brain. And this increase was double in amount in aged learning and memory deficit rats compared to the normal learning and memory aged rats. It is suggested that the mtDNA deletions in the brain regions associated with learning and memory may be contributed to the cellular and molecular mechanism of learning and memory deicit with aged rats. 相似文献
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利用Western-blot技术,对鳗弧菌L-18株的OMPs和IROMPs的免疫反应性进行了分析,并通过免疫牙鲆比较二者免疫保护力的差异,以期从IROMPs方向探索开发鳗弧菌新型鱼用疫苗,并为研究其免疫原理提供重要的科学依据。结果表明,培养基中加入不同浓度的联铁剂,鳗弧菌L-18株的生长和铁载体的表达出现规律性变化,其中加入100~130μmol·L-1 2,2’-联吡啶为最适合限铁条件,此时铁载体的表达量最高且生长受抑制程度较小。在此条件下,菌株表达出74.3ku和77.4ku的IROMPs,其中77.4ku蛋白具有免疫反应性,为重要抗原。用全菌灭活疫苗、OMPs、IROMPs分别腹腔注射免疫牙鲆7周后攻毒, IROMPs疫苗的相对免疫保护力达到75.9%,远高于OMPs疫苗的51.8%。相对于OMPs,IROMPs的抗体效价显著提高,接近全菌疫苗组的水平,而血清杀菌活力没有显著变化。
关键词:鳗弧菌;铁调节外膜蛋白;牙鲆 相似文献