11种杀菌剂对水稻纹枯病菌的毒力比较

采用菌丝生长速率法测定了11种杀菌剂对水稻纹枯病菌的抑菌活性。结果表明，水稻纹枯病菌对三唑类杀菌剂己唑醇、苯醚甲环唑、腈菌唑、戊唑醇、烯唑醇、三唑醇的敏感性依次下降，EC50值均在0．5μg／mL以下，EC90值均低于10μg／mL；水稻纹枯病菌对1227和C8—10两种季铵盐阳离子表面活性剂的敏感性高于井冈霉素，但低于三唑类杀菌剂，EC50分别为15．0394μg／mL和4．0735μg／mL；水稻纹枯病菌对苯并咪唑类杀菌剂甲基硫菌灵和多菌灵毒力差异较大，甲基硫菌灵抑菌活性低于井冈霉素，EC50为10．2330μg,／mL，多菌灵的抑菌活性远高于井冈霉素，其毒力与三唑类药剂相当，其EC50为0．2656μg／mL。     

20%氟胺·嘧菌酯WG和75%戊唑·嘧菌酯WG对水稻纹枯病防效研究

为明确20%氟胺·嘧菌酯WG、75%戊唑·嘧菌酯WG对水稻纹枯病的防治效果及适宜用量等,于2012年在水稻纹枯病发病始盛期和发病高峰期各用药防治1次。结果表明:20%氟胺·嘧菌酯WG 750~1 500 g/hm2、75%戊唑·嘧菌酯WG 150~300 g/hm2对纹枯病1次防治效果在90%以上,2次防治效果在95%以上,与75%肟菌·戊唑醇WG、240 g/L噻呋酰胺SC防治效果相近,好于300 g/L苯甲·丙环唑EC、43%戊唑醇SC、20%井冈霉素AS等处理。     

防治水稻纹枯病的药剂筛选试验

为有效防治水稻纹枯病,对市售药剂进行了田间药剂筛选试验。结果表明:在水稻分蘖期与孕穗期2次施药情况下,240 g/L噻呋酰胺SC防效最好,在95%左右。325 g/L苯甲·嘧菌酯SC、75%肟菌·戊唑醇WG能有效防治水稻纹枯病,药效在80%以上。18.7%丙环·嘧菌酯SC需提高剂量再进行试验。300 g/L苯甲·丙环唑EC防效较差。所有药剂处理对水稻均安全。     

不同杀菌剂防治小麦赤霉病的田间筛选试验

为筛选防治小麦赤霉病的高效药剂,对25%氰烯菌酯SC、42%咪鲜·甲硫灵WP、50%咪鲜胺WP、400 g/L戊唑·咪鲜胺EW和25%多·酮WP进行筛选试验。试验证明:25%氰烯菌酯SC、42%咪鲜·甲硫灵WP和25%多·酮WP对小麦赤霉病的防治效果较好,其用药适期为小麦齐穗扬花期,最佳用药量为25%氰烯菌酯SC 1500 mL/hm2、42%咪鲜·甲硫灵WP 1200 g/hm2和25%多·酮WP 1800 g/hm2,最终防治效果均在85%以上。     

6种杀菌剂对小麦纹枯病示范防治效果的研究

为了筛选防治小麦纹枯病的高效药剂,对生产上常用的6种药剂进行了示范研究。试验结果表明:药后50 d,6种药剂对小麦纹枯病病指防效在46.08%~93.14%之间。240 g/L噻呋酰胺SC 150 m L/hm2、75%肟菌·戊唑醇WG 150 g/hm2对小麦纹枯病的防效在90%以上,持效期长。20%井冈霉素AF 375 g/hm2的防效为85.95%,该药剂成本较低,可以在小麦纹枯病发生初期与240 g/L噻呋酰胺SC、75%肟菌·戊唑醇WG交替使用。75%戊唑·嘧菌酯WG 150 g/hm2药后30,50 d的病指防效均在70%以上,在纹枯病轻发年份可考虑使用。     

烯肟菌胺与噻呋酰胺防治水稻纹枯病的室内毒力测定及田间试验

[目的]探索烯肟菌胺与噻呋酰胺防治水稻纹枯病的效果及剂量。[方法]采用Sun-Johnson法测定室内联合毒力,并验证30%烯肟菌胺·噻呋酰胺SC对水稻纹枯病的防效。[结果]烯肟菌胺与噻呋酰胺对水稻纹枯病菌的EC50值为0.352、0.083 mg/L,烯肟菌胺与噻呋酰胺5∶1~1∶5五个配比具有显著的增效作用;田间药效试验表明,30%烯肟菌胺·噻呋酰胺SC 76~92 g a.i./hm2的用量对水稻纹枯病有较好的防治效果。[结论]30%烯肟菌胺与噻呋酰胺SC用于防治水稻纹枯病,有较好的防治效果。     

浙江省新昌茶叶灰斑病的敏感性测定及田间药效

[目的]通过室内毒力测定和田间药效试验筛选出对茶叶灰斑病具有良好抑制效果的杀菌剂。[方法]采用生长速率法进行了药剂敏感性测定,并对茶叶灰斑病高度敏感的药剂进行了田间药效试验。[结果]室内药剂敏感性测定结果表明:45%咪鲜胺EC、38%唑醚·啶酰菌WG、250 g/L丙环唑EC、65%代森锌WP、70%甲基硫菌灵WP、250g/L吡唑醚菌酯EC、42.8%氟菌·肟菌脂SC、10%苯醚甲环唑WG、25 g/L咯菌腈SD、10%己唑醇SC、325 g/L苯甲·嘧菌酯SC、430 g/L戊唑醇SC和500 g/L异菌脲WP对茶叶灰斑病菌丝生长的抑制效果很好(EC501 mg/L)。田间药效结果表明:45%咪鲜胺EC、250 g/L吡唑醚菌酯EC、250 g/L丙环唑EC、30%嘧菌脂SC和50%异菌脲WP对茶叶灰斑病均有较好的防效。[结论] 45%咪鲜胺EC、250 g/L吡唑醚菌酯EC和50%异菌脲WP均为高效药剂,可生产上推荐使用;为减缓抗药性产生,宜交替使用。     

3种杀菌剂拌种防治向日葵黑茎病药效试验研究

进行了3种杀菌剂对向日葵黑茎病的拌种药效试验,结果表明,3种药剂拌种后对向日葵出苗安全,不产生药害;各个处理的防效均随着向日葵生育进程的推进而下降,以出苗后35 d防效最为理想,此时2.5%咯菌腈FS 11.25 mL/hm2、2.5%咯菌腈FS 9 mL/hm2和50%多菌灵WP 13.5 g/hm2的防效为71.7%～83.4%,显著高于50%多菌灵WP 9 g/hm2、70%甲基硫菌灵WP 13.5 g/hm2和70%甲基硫菌灵WP 9 g/hm2,经方差分析证明处理间差异达到显著水平。     

10种杀菌剂防治水稻纹枯病的田间药效比较

为筛选防治水稻纹枯病的高效、低毒及安全药剂,采用GB/T17980.20-2000的方法,对10种杀菌剂防治水稻纹枯病的田间药效进行了试验比较,并增加调查了病株率防效,以供比较参考。结果表明,250 g/L嘧菌酯悬浮剂防治水稻纹枯病防效为87.53%,20%丁香菌酯悬浮剂、25%丙环唑乳油、10%苯醚甲环唑水分散粒剂、80%戊唑醇可湿性粉剂、15%三唑醇可湿性粉剂防效为71.97%～79.59%,70%甲基硫菌灵可湿性粉剂、10%井冈霉素水剂、240 g/L噻呋酰胺悬浮剂防效为63.92%～66.78%,15%咪鲜胺微乳剂防效为46.73%。病株率防效与病情指数防效趋势一致。试验条件下10个供试药剂对水稻无药害。防治水稻纹枯病可以选用嘧菌酯、丁香菌酯、丙环唑、苯醚甲环唑、戊唑醇、三唑醇等新型高效杀菌剂,优先推荐丁香菌酯。为减缓抗性,建议采用药剂复配或轮用技术。     

3种新药剂总体防治水稻纹枯病、穗颈瘟的效果与应用技术

田间试验结果表明:25%吡唑醚菌酯EC、45%肟菌·己唑醇WG、10%嘧菌酯CS防治水稻纹枯病、穗颈瘟效果明显,适期用药1次对纹枯病、穗颈瘟的防效分别可达80%以上、85%~90%,值得在水稻防治纹枯病、穗颈瘟上推广应用。每667 m~2 25%吡唑醚菌酯EC、45%肟菌·已唑醇WG、10%嘧菌酯CS经济有效用量分别为70 mL、20 g、90 g,此剂量防病效果显著。防治纹枯病最佳用药适期为田间穴发病率5%左右时,兼治稻瘟病;防治水稻穗颈瘟病宜掌握在水稻破口抽穗5%~10%时,兼治水稻纹枯病。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。