螺虫乙酯对B型烟粉虱毒力及部分生物学参数的影响

为系统评价新药剂螺虫乙酯(spirotetramat)对B型烟粉虱(Bemisia tabaci biotype B)的生物活性及生物学参数的影响,采用浸渍法测定了螺虫乙酯及对照药剂吡虫啉对B型烟粉虱各个虫态的室内毒力、成虫寿命、产卵量及所产卵孵化率的影响。结果表明,螺虫乙酯对2龄若虫毒力最高,LC₅₀为4.07 mg/L,为吡虫啉的2.73倍,对卵及成虫毒力较低,且显著低于吡虫啉;12.5 mg/L螺虫乙酯处理后,成虫寿命为17.3天,较空白对照显著缩短,吡虫啉与空白对照无显著差异;12.5 mg/L螺虫乙酯处理后平均产卵量为5.0粒,所产卵的平均孵化率为3.23%,显著低于空白对照和吡虫啉处理,吡虫啉与空白对照无显著差异;100 mg/L螺虫乙酯处理24 h后对烟粉虱成虫驱避率为52%,驱避效果较差。     

哒螨灵对三种害虫的毒力比较及其应用潜力评价

为明确杀螨剂哒螨灵对B型烟粉虱、水稻灰飞虱和黄曲条跳甲等3种害虫的毒力和扩大其使用范围,采用玻管药膜法测定了哒螨灵等药剂对B型烟粉虱和水稻灰飞虱成虫的毒力,用浸渍法测定了哒螨灵等对B型烟粉虱若虫和黄曲条跳甲的毒力.结果显示,哒螨灵对烟粉虱成虫和水稻灰飞虱成虫的毒力最高,触杀LC50分别为0.952 mg/L和0.252 mg/L;哒螨灵对B型烟粉虱若虫的触杀LC50为43.148 mg/L,其毒力较啶虫眯和吡虫啉低,与烯啶虫胺毒力相当,但较吡丙醚毒力高近1倍;哒螨灵对黄曲条跳甲的LC50为195.123 mg/L,其毒力低于毒死蜱,但高于啶虫脒和吡虫啉.表明哒螨灵不仅对B型烟粉虱和水稻灰飞虱成虫毒力高,对烟粉虱若虫和黄曲条跳甲的毒力也较高,有进一步开发应用的潜力.     

溴氰虫酰胺对B隐种和Q隐种烟粉虱不同虫态的毒力研究

系统测定了新型双向传导高效杀虫剂溴氰虫酰胺对B隐种和Q隐种烟粉虱卵、若虫和成虫不同虫态的毒力。结果发现,溴氰虫酰胺对烟粉虱卵、若虫具有极高的毒力。用浸茎系统测定法测定其对B隐种和Q隐种烟粉虱不同虫态的LC50值,对0~1日龄卵分别为0.008 99、0.924 mg/L,对1~4龄若虫分别为0.003 36、0062 7 mg/L,对1日龄成虫分别为6.23、93.9 mg/L。对溴氰虫酰胺的敏感性,以3龄若虫最高,其次是2龄、1龄和4龄若虫,B隐种烟粉虱的敏感性更高。用着卵叶片浸渍法和浸茎系统测定法证明该杀虫剂具有很强的内吸杀卵作用,同时发现该药剂有一定的触杀杀卵活性。由于该杀虫剂对烟粉虱卵和若虫的高毒力和极强的双向内吸传导性能,推测其将成为未来一段时间内防治田间烟粉虱以及其他刺吸式口器害虫的重要药剂。     

烯啶虫胺对烟粉虱的使用技术及抗性风险评估研究

采用室内生物活性测定法系统测定了烯啶虫胺对烟粉虱不同虫态的毒力、成虫持效性、抗性风险评估和不同施药方法田间药效试验。结果表明,烯啶虫胺对烟粉虱低龄若虫和高龄若虫均表现出较高毒力,对成虫也有一定毒力,而对卵效果较差。烯啶虫胺水剂100 mg/L处理时对烟粉虱成虫1～15 d的校正死亡率在80.18%～92.13%之间,随着时间的延长,烯啶虫胺对烟粉虱的防效降低。烯啶虫胺喷雾和灌根方法效果较好,从速效性来说,喷雾好于灌根,从持效性来说,灌根优于喷雾,两种方法均显著高于单叶施药和涂茎法。经过8代6次选育,烟粉虱对烯啶虫胺抗性发展缓慢,与选育前相比敏感性降低2.653倍,烟粉虱对烯啶虫胺的抗性现实遗传力为0.102 5,在50%～90%的筛选压力下,要获得10倍抗性,需要9～21代,表明烟粉虱对烯啶虫胺有产生抗性的风险。     

6种药剂防治大棚番茄烟粉虱效果

比较了6种杀虫剂对大棚番茄烟粉虱成虫和低、高龄若虫的防治效果。22.4%螺虫乙酯悬浮剂和300 g/L氯虫·噻虫嗪悬浮剂对烟粉虱3种虫态的防控效果均较好,对成虫防效尤佳,药后7 d校正防效达61.6%和51.2%。1.8%阿维菌素乳油和99%矿物油乳油对烟粉虱若虫用药7d后防效也较为理想。从虫态上看,6种药剂对烟粉虱高龄若虫的防治效果明显低于对低龄若虫的防治效果。     

药剂对B型烟粉虱不同虫态的毒力和对成虫的驱避效应

啉和噻虫嗪对烟粉虱成虫的驱避效果好,持效期可达15天;绿颖矿物油对成虫的驱避率较高,并有较好的杀卵作用.     

吡丙醚和烯虫酯对嗜卷书虱控制作用的研究

采用饲料混毒法系统测定了吡丙醚和烯虫酯两种昆虫生长调节剂(IGRs)对重要的储藏物害虫嗜卷书虱Liposcelis bostrychophila Badonnel若虫和成虫的致死作用,对若虫发育情况、成虫繁殖力和卵孵化率的影响。结果表明,以吡丙醚和烯虫酯10 mg/kg的混毒饲料饲喂嗜卷书虱2龄幼虫49 d后,若虫的死亡率分别为80.00%和31.11%;取食20、10和5 mg/kg吡丙醚的若虫最长存活天数分别为71.0、98.2和116.4 d,而对照仅11.3 d即全部羽化为成虫;取食20 mg/kg以下烯虫酯混毒饲料的若虫一部分仍可羽化成成虫,而且成虫仍可繁殖后代;取食吡丙醚混毒饲料的若虫,60 d后存活下来的若虫大多以超龄若虫的形式存在,而取食烯虫酯的若虫则很少出现超龄若虫。成虫取食烯虫酯(200 mg/kg)和吡丙醚(40 mg/kg)混毒饲料后7 d,死亡率分别为26.67%和23.33%,成虫产卵量分别是对照的39.77%和26.13%,产卵后15 d,卵的孵化率分别是65.71%和8.69%,而对照仅为93.18%。该项研究表明,采用40 mg/kg吡丙醚和200 mg/kg的烯虫酯对嗜卷书虱虫口数量有明显的控制作用。     

20%噻虫胺悬浮剂防治柑橘木虱田间药效试验

应用20%噻虫胺SC进行柑橘木虱田间药效试验,结果表明:20%噻虫胺SC 1 500倍液、2 000倍液和2 500倍液,施药后1 d对若虫的防效分别为89.93%、85.07%和81.01%,对成虫的防效分别为91.67%、85.55%和81.65%;施药后10 d对若虫的防效均为100%,对成虫的防效分别为100%、88.89%和84.40%,由此可见20%噻虫胺SC对柑橘木虱的防效好,具有速效性快、持效期长等特点。     

8种不同类型杀虫剂对MED烟粉虱隐种的防治效果及其残留检测

为筛选对设施蔬菜烟粉虱具有高效、低毒、低残留的化学农药,选用8种分属于不同类型的杀虫剂对设施黄瓜和茄子上的MED烟粉虱隐种进行了药效试验和农药残留检测。结果表明,药后10d,8种杀虫剂对黄瓜田MED烟粉虱的防效为78.98%~96.66%,而对茄子田MED烟粉虱仅为39.59%~81.11%。新型杀虫剂10%溴氰虫酰胺OD和50%氟啶虫胺腈WG对MED烟粉虱防效高,药后10d对黄瓜田MED烟粉虱的防效分别达94.90%和94.18%,对茄子田MED烟粉虱的防效分别达75.24%和81.11%;3种新烟碱类杀虫剂药后10d对黄瓜田MED烟粉虱防效为78.98%~89.22%,对茄子田MED烟粉虱的防效60.58%~79.09%。酰肼类拟脱皮激素类240g/L甲氧虫酰肼SC药后10d对黄瓜田和茄子田MED烟粉虱的防效分别为80.79%和80.41%。10%溴氰虫酰胺OD中添加增效剂乙氧基改性聚三硅氧烷可使药后3~14d防治效果显著提高1.86%~67.40%。残留检测结果表明,在推荐使用剂量下,药后15d黄瓜茎叶中噻虫嗪和啶虫脒的平均残留量分别为0.52mg/kg和2.06mg/kg,茄子茎叶中阿维菌素、吡蚜酮、甲氧虫酰肼的平均残留量为0.031mg/kg、2.36mg/kg和4.75mg/kg,均高于我国对果实的最大残留限量标准,而黄瓜果实样品中7种杀虫剂均未检出(0.01mg/kg)。研究表明,10%溴氰虫酰胺OD和50%氟啶虫胺腈WG是防治设施蔬菜MED烟粉虱较为理想的新型杀虫剂。     

印楝素亚致死浓度对烟粉虱实验种群的生物活性

在室内条件下,以2个亚致死浓度（0.15和0.30mg/L）喷雾处理烟粉虱1、5日龄卵,明确了印楝素亚致死浓度对烟粉虱实验种群发育、存活、繁殖均具有显著的抑制作用。其中,印楝素处理1日和5日龄卵分别使幼期（卵至成虫羽化）发育历期延长0.92至2.84d,幼期存活率降低了56.3%至89.6%,若虫虫体长宽减小,雌成虫寿命降低29.8%至48.6%,平均单雌产卵量降低49.8%至72.5%。清水对照、0.15mg/L和0.30mg/L印楝素溶液处理1日龄卵,烟粉虱实验种群的内禀增长率分别为0.227、0.0742和0.060,净增殖率依次为36.40、7.29和5.33;处理5日龄卵时两者分别为0.126、0.114和0.059与39.192、3.59和4.93。     

细辛醚对家蝇和淡色库蚊的生物活性

为了进一步确定细辛醚的作用谱和作用方式,测定了其对家蝇和淡色库蚊的触杀、熏蒸和忌避活性。结果表明:细辛醚对家蝇4 h的触杀LD50值为3.45 μg/头;对家蝇、淡色库蚊4 h的熏蒸LC50值分别为5.77和4.24 μL/L;对两者在LC80剂量下熏蒸处理的击倒中时(KT50)值分别为11.64和4.80 min;在1 mg/mL的浓度下,对家蝇的忌避率为81.82%。中毒家蝇依次表现出兴奋、痉挛、麻痹和死亡等症状。     

莰酮对柑桔天牛的生物活性

在室内测定了樟树(Cinnamomum camphora L.)天然产物莰酮-[2](Cam-phor C10H16O)的杀虫活性和作用方式，并进行了田间试验。结果表明，莰酮对天牛成虫有较强的驱避、熏蒸和触杀作用。每点投放2％莰酮DP1-2g，药后24h对天牛驱避效果为55．00％-85．00％，药后72h达到94．12％-100．00％；熏蒸致死中浓度为8．20mg/L，触杀致死中浓度为15．25mg／L。经回归和相关分析，处理浓度与作用效果相关性均达到极显著水平。每洞穴喷2％莰酮DP0．1-0．2g，对天牛幼虫防治效果达85．80％-100％；每袋装2％莰酮DP1．5-2．5g，药后7-15天对天牛成虫驱避效果为80．95％-100％。药后30-60天为68．29％-86．36％，田间防治效果显著。     

山苍子精油对白纹伊蚊的生物活性及其成分分析

研究了山苍子Litsea cubeba果实精油对白纹伊蚊Aedes albopictus成蚊的驱避活性和对其幼虫的毒杀活性;采用GC-MS定性分析了精油的化学成分,并定量分析了其中9种活性成分。结果如下：在1．5mg·cm^-2的涂抹剂量下,山苍子精油对白纹伊蚊的100％保护时间为3．70h,对白纹伊蚊4龄期幼虫的24h毒杀Lc50值为82．48μg·mL^-1。定性分析共鉴定出17种化合物,其中E-柠檬醛的相对含量最高,其峰面积百分比为44．65％,其它相对含量较高的成分分别是Z-柠檬醛（34．60％）、柠檬烯（11．70％）、甲基庚烯酮（2．28％）、芳樟醇（1．28％）等。定量分析9种活性成分在精油中的总含量为238．70mg·mL^-1,其中E-柠檬醛106．20mg·mL^-1、Z-柠檬醛68．79mg·mL^-1、桉叶油素40．90mg·mL^-1的含量较高。研究结果表明,山苍子精油对白纹伊蚊具有良好的成蚊驱避和幼虫毒杀活性,这些生物活性与精油的化学成分密切相关。     

4种植物精油对瓜实蝇毒杀及驱避作用

瓜实蝇 Bactrocera cucurbitae (Copullett)是我国瓜类蔬菜的重要入侵害虫, 为筛选出对瓜实蝇具有毒杀及驱避作用的植物精油, 室内测定了4种植物精油在不同浓度下对瓜实蝇的毒杀及产卵驱避效果, 并进行了田间验证。结果表明:4种植物精油对瓜实蝇成虫的毒杀效果随精油浓度升高而升高, 浓度为7 mg/mL和10 mg/mL的肉桂精油对瓜实蝇的毒杀效果极显著高于其他精油, 处理后24 h瓜实蝇校正死亡率分别为75.9%和100%;雌虫对冬青精油的嗅觉反应率为93.3%, 显著高于紫苏精油和山苍子精油。不同植物精油对雌虫产卵的驱避效果不同，当植物精油浓度为10 mg/mL时, 冬青精油对雌虫的产卵驱避率为69.04%, 显著高于其他精油。田间试验结果显示:不同植物精油对瓜实蝇成虫具有一定防控效果, 但处理间差异不显著, 可能是由于田间环境复杂、植物精油理化性质存在差异等因素导致。     

Experimental chemotherapy of Angiostrongylus cantonensis infection in mice with flubendazole, levamisole, and their combination

The efficacy of the drugs flubendazole, levamisole, and their combination was studied against Angiostrongylus cantonensis infection in mice. The drugs were evaluated on day 15 post infection. The efficacy was assessed by using single-dose and 5-dose treatment schedules. Flubendazole was effective at 25 mg/kg, 50 mg/kg, 100 mg/kg, 200 mg/kg when given each day for five days. Levamisole at a dose rate of 200 mg/kg was completely effective in a single treatment. The combined therapy of levamisole (25 mg/kg) and flubendazole (15 mg/kg) produced 100% efficacy. Both drugs given prior to experimental infection showed no prophylactic activity.     

6种植物乙醇提取物对桔小实蝇成虫的毒杀和产卵驱避作用的初步研究

为筛选出对桔小实蝇成虫有效毒杀和产卵驱避的植物乙醇提取物,采用超声提取法制备了紫茎泽兰、臭椿、菖蒲、青蒿、臭牡丹、樟树等6种植物提取物,并测定提取物对桔小实蝇成虫的毒杀和产卵驱避活性。结果表明:紫茎泽兰、青蒿、臭椿和菖蒲的乙醇提取物均对桔小实蝇成虫有较强的毒杀作用,当浓度为100 mg/mL时,校正死亡率均为100%。臭牡丹和樟树的乙醇提取物对桔小实蝇成虫表现出较弱的毒杀性。6种植物乙醇提取物随着浓度的增加,对桔小实蝇成虫的毒杀作用表现增强。产卵驱避活性测定试验中,6种植物提取物均对桔小实蝇有一定的产卵驱避活性,且随着提取物的浓度增大,产卵驱避率增高。当浓度为100 mg/mL时,紫茎泽兰和臭椿的乙醇提取物的效果较好,产卵驱避率分别为84.35%和81.46%,其次是菖蒲的提取物,产卵驱避率为65.15%,青蒿、臭牡丹和樟树的提取物也表现出一定的产卵驱避效果,产卵驱避率分别为52.71%、59.22%和51.02%。     

Prallethrin induced serum biochemical changes in Wistar rats

The present study was designed as a repeated dose 28-day oral toxicity study in rodent. All the rats were randomly divided into five groups (C1, C2, T1, T2 and T3) each containing 10 Wistar rats (5 male and 5 female). Group C1 served as control as no treatment was administered. Group C2 was administered groundnut oil (1 ml/100 g b.wt) and served as vehicle control. Group T1 was put on high dose 153.33 mg/kg b.wt (LD50/3), while group T2 received intermediate dose of 92 mg/kg b.wt (LD50/5), and group T3 was administered low dose of 46 mg/kg b.wt (LD50/10) of Prallethrin suspended in 1 ml/100 g b.wt of groundnut oil. Blood samples were collected from all groups on the 7th, 14th, 21st and 28th day of the experiment for measurement of serum glucose, serum urea, serum triglyceride, serum cholesterol, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT) and serum alkaline phosphatase (ALP). According to data obtained on the 7th day of the study, no statistically significant change in any of the treatment groups was observed as compared to the control group. On the 14th day of the study, in comparison to the control group, triglyceride level and ALP activity were found to be significantly increased in the group T1 female and group T1 male rats respectively. On the 21st day of the study, compared to the controls, significant increase in cholesterol and ALP levels were present in both T1 and T2 females and in addition to this total protein and triglycerides levels were also significantly increased in group T1 female rats. In group T1 male total protein, triglycerides, ALT and ALP activity was found to be increased significantly as compared to healthy control group. On the 28th day, all the recorded biochemical parameters were found to be significantly increased, except BUN and AST in group T1 female rats. In group T2 female rats, significantly increased cholesterol, ALT and ALP levels were observed. In group T3 female rats, none of the parameters were found to be significantly affected. Among male rats, only total protein level was found to be increased in groups T2 and T3. Whereas, total protein, triglyceride, ALT and ALP were significantly elevated in group T1 male rats at the end of the study. In conclusion, the results of this study demonstrate that subacute oral administration of Prallethrin; at dose levels of 1/3 LD50 and 1/5 LD50 for 28 days induces moderate toxic effects on different biochemical parameters.     

Repellency of Cinnamomum cassia bark compounds and cream containing cassia oil to Aedes aegypti (Diptera: Culicidae) under laboratory and indoor conditions

Patch and skin bioassays were used in laboratory and indoor tests to evaluate the repellency of (E)-cinnamaldehyde, identified in Cinnamomum cassia Blume bark and essential oil, and a cream containing 5% (w/w) cassia oil against Aedes aegypti (L.) females. Results were compared with those of a known C. cassia compound cinnamyl alcohol, N,N-diethyl-m-toluamide (DEET) and two commercial repellents: MeiMei cream containing citronella and geranium oils and Repellan S aerosol containing 19% DEET. In patch bioassay tests with A. aegypti females, (E)-cinnamaldehyde at 0.153 mg cm(-2) and DEET at 0.051 mg cm(-2) provided 93 and 89% protection at 40 min after exposure. In skin bioassay tests, (E)-cinnamaldehyde at 0.051 mg cm(-2) and DEET at 0.025 mg cm(-2) provided 87 and 95% protection at 30 min after application. (E)-Cinnamaldehyde was significantly more effective than cinnamyl alcohol in both bioassays. In indoor tests with four human volunteers, 5% cassia oil cream provided 94, 83 and 61% protection against A. aegypti females exposed for 30, 50 and 70 min after application respectively. Cassia oil cream was a slightly less effective repellent than MeiMei cream. Repellan S aerosol provided 91% repellency at 120 min after application. Products containing cassia oil merit further study as potential repellents for the protection of humans and domestic animals from blood-feeding vectors and the diseases they transmit.     

蒙古蒿挥发油对三种主要枸杞害虫的控制作用

为保障枸杞产品质量安全,采果期不受化学农药干预,本研究通过室内毒力测定和田间药效试验评价了蒙古蒿挥发油的杀虫活性。结果表明,蒙古蒿挥发油对棉蚜的LC₅₀为7.82mg/mL;对枸杞木虱的LD₅₀为2.89μg/头;对西花蓟马的LC₅₀为2.80mg/mL,均低于对照药剂印楝素提取物,其中胡椒酮、PPG2-甲醚和桉油烯醇起主要杀虫作用。利用响应面分析,蒙古蒿挥发油制备成8.5%蒙古蒿挥发油微胶囊剂,该制剂在质量浓度6kg/hm²条件下,药后1d,对枸杞蚜虫、西花蓟马和枸杞木虱的防效分别为75.95%、58.81%和32.14%,高于对照0.3%印楝素乳油,杀虫效果一直持续到21d。本研究将蒙古蒿挥发油微胶囊应用于枸杞园采果期防治主要害虫,持效期长,具有进一步开发成高效植物源农药的潜力。     

Laboratory trials of fatty acids as repellents or antifeedants against houseflies,horn flies and stable flies (Diptera: Muscidae)

BACKGROUND: Straight‐chain, saturated fatty acids (particularly C8, C9 and C10) have some known behavioral effects on insects such as mosquitoes, and were tested in combination for potential repellency/antifeedant activity in bioassays against three significant muscoid flies of medical/veterinary importance: houseflies, horn flies and stable flies. RESULTS: Mixtures of C8, C9 and C10 (1:1:1; 15% total actives in formulation) were highly repellent to houseflies and horn flies at or below 1 mg formulation cm^?2. Repellency time varied from < 1 day for houseflies to usually at least 3 days for horn flies. Individual longer‐chain‐length fatty acids were tested, and C11 repelled houseflies for up to 5–8 days, while C12 lasted 2 days. Minimum statistically significant repellency levels of the C8, C9 and C10 mixture (3 h after application) against horn flies were 0.06–0.12 mg cm^?2. A liquid formulation of the 15% C8, C9 and C10 mixture in a silicone oil carrier (at 2.8 mg AI cm^?2) was highly repellent against hungry stable flies in a blood‐feeding membrane bioassay for at least 8 h. CONCLUSION: The low toxicity and reasonable activity and persistence of these carboxylic acids make them good candidates for development as protective materials against pest flies in livestock settings. Copyright © 2009 Society of Chemical Industry