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91.
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氟虫腈(锐劲特)对水稻害虫防治效果及增产效应 总被引:6,自引:0,他引:6
为了阐明新一代杀虫剂氟虫腈(锐劲特)对二化螟、三化螟、稻纵卷叶螟的防治效果及应用前景,进行了水稻盆栽试验、田间防效试验,并对施用锐劲特后水稻叶绿素含量、功能叶叶面积和产量进行了测定。结果表明,锐劲特施药后13天接虫的三化螟幼虫死亡率仍高达94.44%。在田间防效试验中,每公顷施用锐劲特80%WG有效成分24g防治二化螟,防止枯心效果达97.62%,防止白穗效果达94.44%,害虫死亡率达96.15%;每公顷施用锐劲特5%SC有效成分22.5g防治晚稻三化螟,保苗效果可达95.91%,害虫死亡率达99.04%;每公顷施用锐劲特5%SC有效成分30g防治稻纵卷叶螟,保叶效果达97.88%。叶绿素含量比对照增加32.4%;每公顷施用锐劲特80%WG有效成分36g时,功能叶叶面积增加16%~27.5%,并且杂交稻博优湛19比常规稻早糯3321和早熟早籼815对锐劲特更敏感。每公顷施用锐劲特5%SC有效成分22.5~37.5g时,水稻株高增加4.0~6.1cm,每稻丛穗数增加2.6%~31.18%,结实率提高19.43%~33.97%,水稻产量增加21.58%~28.19%。 相似文献
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菌丝融合型测定结果表明,32个茭白纹枯病菌菌株隶属于两个菌丝融合群:30个属AG1群,占测定菌株的93.95%,其中AG1-IA、AG1-IC两亚群菌株依次为24与6,有两菌株为AG4,占6.25%。显然,AG1-IA为优势融合群,占测定菌株的75%。融合群致病性测定结果表明,AG1-IA致病性强,AG1-IC弱,AG4基本不致病。茭白与水稻两种纹枯病菌交互接种,其发病基本一致。由此,作者认为这两种纹枯病菌为同一病原物,或者说茭白、水稻是同一病原物的两个寄主植物。 相似文献
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AIM:To investigate the effect of the heat shock response on the reperfusion arrhythmias(RAs) and the possible mechanism involved. METHODS:Fifty-five Sprague Dawley rats were randomly divided into 2 groups: the heat shock group (group H,n=29) and the control group (group C,n=26). The rats in group H were preconditioned with heat shock 24 hours before, and that in group C were not. The hearts of 16 rats in group H and 16 in group C were exercised and mounted on a non-circulating Langendorff perfusion apparatus and perfused retrogradely with modified K-H buffer and mimic ischemia/reperfusion was applied. Additionally, conventional intracellular microelectrode techniques were used for recording such electrophysiological parameters as resting potential(RP), action potential amplitude(APA), over shot(OS), maximum depolarization velocity(Vmax) of the hearts of other 13 rats in group H and 10 in group C. RESULTS:①Prior heat stress significantly decreased reperfusion arrhythmia. ②The amount of CK release in the effluent in group H was much less than that in group C. ③Myocardial HSP70 content was elevated significantly in group H. ④Heat stress significantly increased myocardial anti-oxydases activity and decreased lipid peroxydative products. Additionally, heat stress significantly reduced the Vmax of action potential. It indicated that rapid Na+ channel of papillary muscles may be inhibited by heat shock. The degree of change of Vmax after ischemia in H group was significantly less than that in group C. And the time of reperfusoin with Tyrode's solution till the action potential appeared as large as that before perfusion with mimic ischemic solution is shorter in group H than in group C. CONCLUSION:Heat shock pretreatment markedly reduces ischemia/reperfusion-induced injury of heart and ventricular arrhythmias in rats and this effect may be associated with the inhibition of rapid Na+ channel of papillary muscles by heat shock and the increase in myocardial HSP70 and anti-oxydase activity. 相似文献
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CHEN Xiao-yin ZHANG Qun YANG Qin-he XIE Qiu-ling SHEN Qiang XU Yun-sheng 《园艺学报》2002,18(12):1529-1531
AIM: To examine the effect of traditional chinese medicine recipe, Taoren Honghua(semen persicae-flos carthami) decoction, on hyperlipidemia without symptom. METHODS: The plasma TC, TG, LDL, HDL, apolipoprotein(Apo) A, Apo Bof the patients with hyperlipidemia without symptom were measured using automatic analyzer (shimadiu CL-7200), the production of nitric oxide(NO) was detected by Greiss reaction, and SODactivity and MDAformation were examined using o-trihydroxy benzene and barbituric methotheds, respectively. RESULTS: After oral administration of Taoren Honghua decoction, the plasma levels of TC, TG, LDL, and MDAof the patients were markedly decreased, however, the plasma levels of ApoA, HDL, SODand NOwere significantly increased and almost no change was detected in the plasma level of Apo B. In control group, it was found that although the plasma level of TC, TG and LDL were decreased ( P<0.05 ) and ApoAas well as HDLwere increased, ApoB, SOD, MDA and NO production were all unchanged. CONCLUSION: The traditional chinese medicine recipe, Taoren Honghua decoction,has a significant therapeutic effect on patients with hyperlipidemia by removing blood stasis, promoting qi circulation and in turn reducing blood lipid level. 相似文献
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