白纹伊蚊对光线与二氧化碳的行为反应

白纹伊蚊Aedesalbopictus是重要的媒介昆虫 ,骚扰叮咬、传播病菌 ,严重危害人体健康。该文利用市场上流行的不同型号的 2种驱蚊灯和 4种诱蚊灯分别处理白纹伊蚊种群 ,观测其行为反应 ,结果表明白纹伊蚊在活动、取食和存活等方面均产生保护性行为反应。未照射 (CK)蚊子生长正常、活动性强、取食活跃、存活率高。除虫灯光线照射后 ,初期 ( 1d内 )蚊子活泼、活动量较大、存活率较高 ;前期 ( 1～ 3d间 )活动加剧、取食减少而存活率降低 ;一定时期 ( 3d)后活动性逐渐降低、取食越来越少、存活率明显下降。除虫效果检测表明 ,诱蚊灯的诱杀效果比驱蚊灯的驱逐作用对减少蚊虫的数量更明显 ;同时显示 ,诱蚊灯的灭蚊效果均较好 ,但诱蚊作用不十分理想。继而探索出一个对白纹伊蚊具有较好引诱效应的二氧化碳 (CO2 )浓度 4 464× 1 0 -4mol L ,并与紫外线诱蚊灯结合试验表明 ,一定浓度的CO2 能够显著提高诱蚊灯的诱杀效果 ,这可为开辟蚊虫物理防治新途径提供理论依据。     

以壳聚糖为载体束缚脂肪酸吸附CO2在诱捕白纹伊蚊中的应用研究

为了从壳聚糖+脂肪酸离子液体吸附CO2化合物中筛选出对白纹伊蚊Aedes albopictus具有良好引诱效果的化合物，采用陷阱诱捕法分别测定了壳聚糖+丙酮酸、壳聚糖+乙酸、壳聚糖+丙酸 3种脂肪酸离子液体化合物及其吸收CO2对白纹伊蚊成虫的诱捕效果。结果表明，在供试的3种脂肪酸离子液体中，等物质的量吸收CO2的性能依次是丙酮酸>乙酸=丙酸，对白纹伊蚊的诱蚊效果依次是丙酮酸>乙酸=丙酸。其中最优配方比是壳聚糖∶丙酮酸∶CO2=1∶25∶0.3621，平均累计诱蚊量比单组分丙酮酸增加31.37%，比单组分CO2增加30.73%,比对照纯水增加59.52%（P<0.05）。相同质量的3种脂肪酸吸附CO2，具有协同增效作用，平均累计诱蚊量均显著优于单组分脂肪酸（P<0.05）。现场诱蚊试验结果表明，壳聚糖对3种脂肪酸均有缓释作用，其诱蚊持效期延长1.71~3.00倍。根据离子液体原理以壳聚糖为载体束缚脂肪酸吸附CO2并结合陷阱诱捕器，能够显著提高对白纹伊蚊的诱捕数量（混合物60 d的累计诱蚊总数量是单组分的1.62~1.78倍）。研究结果为进一步开发可适用于家居办公环境中使用的诱蚊剂提供了研究基础。     

竹叶花椒果实精油对两种蚊虫的毒杀活性研究

采用浸液法测试了竹叶花椒果实的水蒸汽蒸馏精油对白纹伊蚊和致倦库蚊幼虫的毒杀效果,并用三角瓶密闭熏蒸法研究了精油对这两种成蚊的熏杀活性;此外,采用GC-MS分析了该精油的化学成分。研究结果:(1)精油对白纹伊蚊和致倦库蚊的Ⅰ、Ⅱ、Ⅲ、Ⅳ龄期幼虫及蛹的LC50值分别为25.634/61.472、31.763/76.431、52.356/110.172、258.497/121.884和198.263/162.048mg.L-1;(2)精油对白纹伊蚊和致倦库蚊成蚊的LC50值分别为24.957和29.517μg.cm-3;(3)在147.52μg.cm-3熏杀剂量下,精油对白纹伊蚊和致倦库蚊成蚊的KT50值分别为3.493和2.993min,24h致死率均为100%;(4)共鉴定出18种化合物,其中萜烯类10种,占精油总量的67.122%,为竹叶花椒果实精油的主要成分。竹叶花椒果实精油对白纹伊蚊和致倦库蚊均有明显的致死作用,且作用速度快,具有开发为植物源杀蚊剂的潜力。     

白纹伊蚊对几种引诱物的行为和触角电位反应

【目的】了解引诱物对白纹伊蚊Aedes albopictus行为及触角电生理影响,以揭示白纹伊蚊吸血与传病的行为机制。【方法】采用行为学和触角电位学的方法分别测定了L-乳酸、氨、1-辛烯-3-醇对白纹伊蚊的行为反应和触角电位强度变化,并分析了几种引诱物对白纹伊蚊活性的影响及其规律。【结果】氨、L-乳酸和1-辛烯-3-醇3种引诱物的引诱效果和触角电位变化趋势相同,随着引诱物浓度的增加,对白纹伊蚊的引诱效果和触角电位强度也相应增强。同等浓度下氨对白纹伊蚊的引诱效果较另外两种引诱化合物更显著,且1-辛烯-3-醇的引诱效果相比L-乳酸要更强。当引诱化合物浓度在1 mg/L以上时,白纹伊蚊触角电位反应增幅随着浓度增大也逐渐增大;在引诱化合物浓度达1 000 mg/L时,白纹伊蚊对氨的触角电位反应最强烈。【结论】行为学和触角电位的研究手段相结合能更为全面地反映和评价不同引诱物对蚊虫的引诱效果。     

挥发性脂肪酸铵盐在诱捕白纹伊蚊中的应用研究

【目的】评价6种化合物及其混合物在野外现场对白纹伊蚊Aedes albopictus成虫诱捕的效果。【方法】采用陷阱诱捕法分别测定了乙酸、丙酸和辛酸3种脂肪酸及其铵盐对白纹伊蚊的诱捕效果,并分析了几种引诱物对白纹伊蚊活性的影响及其规律。【结果】在供试的6种化合物中,乙酸、丙酸和辛酸3种脂肪酸及其铵盐(乙酸铵、丙酸铵和辛酸铵)诱捕效果显著,同剂量的各化合物对白纹伊蚊的诱蚊效果依次是乙酸>丙酸=辛酸=乙酸铵>丙酸铵>辛酸铵。相同质量脂肪酸(乙酸、丙酸、辛酸)∶脂肪酸铵(乙酸铵、丙酸铵、辛酸铵)=1∶1至1∶4的配方比,其平均累计诱捕量均显著优于其单组分及对照水(P<0.05)。说明脂肪酸(乙酸、丙酸、辛酸)与脂肪酸铵(乙酸铵、丙酸铵、辛酸铵)混合具有协同增效作用。其中最优配方比是[脂肪酸(乙酸、丙酸、辛酸)]∶[脂肪酸铵(乙酸铵、丙酸铵、辛酸铵)]=1∶2,平均累计诱捕量分别比单组分脂肪酸增加27.56%、27.66%、26.98%,分别比单组分脂肪酸铵增加41.64%、41.18%、40.35%和分别比对照水增加72.29%、72.25%、72.66%(P <0.05)。【结论】现场诱蚊试验结果表明,根据相似相溶原理将脂肪酸与脂肪酸铵混配并结合陷阱诱捕器,能够显著提高对白纹伊蚊的诱捕数量,延长诱蚊时间。脂肪酸铵味道不大,有望替代气味刺激的脂肪酸,可适用于家居办公环境中使用。     

上海常见蚊种对犬丝虫(Dirofilaria immitis Leidy，1856)Railliet and Henry，1911)的感染试验

以上海常见蚊种：淡色庙蚊、三带喙库蚊、中华按蚊、白纹伊蚊、骚扰阿蚊和棕垲麻蚁等6咱,在相似条件下进行对犬丝虲的人工感染试验。结果证明犬丝虫能在白纹伊蚊、中华按蚊、淡色库蚊及三带喙庸蚊完垒傲育;骚援阿蚊吸血後,所有进入马氏管中的微丝蚴全成角質化,不能发育;棕尾麾蚊不能吸血,无法观察。各试验种中以感染率论,淡色庙蚊最高,中摹按蚊和白纹伊蚊次之,三带喙庵蚊最低。以发育率论,中华按蚊最高,白纹伊蚊次之,淡色库蚊和三带喙庳蚊最低。以蚊虫存活率论,淡色库蚊和白纹伊蚊最高,三带喙应蚊次之,中莘按蚊最低。根攘Kartman氏(1954)所建议的实验戚染指敷比较各蚊种的感受力,试验蚊植中以白纹伊蚊最高,淡色库蚊和中华按蚊次之,三带喙库蚊最低。各蚊种的吸犬血率,在实验室条件下,以白纹伊蚊为最高,中华按蚊次之,三带喙库蚊及骚扰阿蚊及淡色库蚊次之。上述试验结果指出四种蚊虫中,以白牧伊蚊为最適宜的试验媒介,也可能是自然媒介;中华按蚊灾之,其他二种库蚊更次之,似不重要。     

登革Ⅱ型病毒经白纹伊蚊滞育卵的传递

采用C6/36细胞培养分离病毒的方法检测感染登革Ⅱ型病毒的白纹伊蚊Aedes albopictus滞育卵孵化的F₁代蚊虫感染率,从第一个生殖营养周期子代蚊虫中未分离到病毒,第二与第三生殖营养周期子代蚊虫最低感染率没有显著性差异（χ²=0.01,P＞0.0 5）,感染子代的批阳性率为9.1%,最低感染率为1∶330;间接免疫荧光检测结果表明感染登革Ⅱ型病毒的白纹伊蚊滞育卵孵化的子代成蚊能通过叮咬将登革病毒传播给敏感乳鼠。这些研究结果表明登革病毒能在媒介滞育卵内存活并传至子代,子代蚊虫能通过叮咬敏感宿主水平传播病毒。     

白纹伊蚊抗溴氰菊酯品系的筛选及其对登革病毒的易感性

【目的】建立白纹伊蚊Aedes albopictus抗溴氰菊酯的蚊虫品系,对比白纹伊蚊敏感株和抗性株对登革病毒的易感性差异。【方法】采用浸渍法测定溴氰菊酯对白纹伊蚊幼虫的半数致死浓度(LC_(50));再以LC_(50)水平的溴氰菊酯对白纹伊蚊幼虫进行群体筛选至第11代,并通过接触筒法检测各代成蚊抗性。以白纹伊蚊敏感株和获得的抗性株(第9代)雌蚊吸食含2型登革病毒(DENV-2)的血餐,于感染后0,4,7和10 d解剖蚊虫,收集中肠、卵巢和唾液腺,通过RT-PCR和实时荧光定量PCR分别检测各组织的DENV-2病毒感染率和感染量。【结果】白纹伊蚊经溴氰菊酯筛选至第9代后抗性趋于稳定。第9代抗性株幼虫的LC_(50)为0.053 mg/L,抗性倍数为10.58,成蚊生测的蚊虫死亡率为80%,已达到中度抗性。感染后0 d,所有蚊虫的中肠均可测得DENV-2,而且抗性株的平均病毒感染量高于敏感株;后续时间点敏感株与抗性株蚊虫中肠均保持92.75%~97.18%的病毒感染率,且二株之间无显著性差异(P0.05)。感染后4 d,两株蚊虫的卵巢中均可检测到DENV-2,感染后7 d和10 d的卵巢病毒感染率均显著高于4 d时(P0.05),但在7 d和10 d两个时间点,敏感株和抗性株之间均无统计学差异(P0.05),然而抗性株平均病毒感染量在每一个时间点都显著高于敏感株(P0.05)。蚊虫唾液腺于感染后7 d检测到DENV-2,10 d时唾液腺的病毒感染率无明显升高且两株蚊虫之间病毒感染率和感染量均无统计学差异(P0.05)。【结论】经溴氰菊酯的筛选使白纹伊蚊幼虫及成蚊抗性水平逐渐升高,建立了白纹伊蚊抗溴氰菊酯的实验室品系。DENV-2对白纹伊蚊抗性株和敏感株各个组织的感染率相近,但感染量有所不同,说明对溴氰菊酯有中度抗性的白蚊伊蚊对登革病毒的易感性在一定程度上发生了改变。     

重庆常见蚊科越冬初步观察

重庆蚊子种类很多,其中与人关系最密切的有中华按蚊、致倦库蚊、白纹伊蚊、骚扰阿蚊等四种,它们如何越冬,在消灭蚊子与疾病防治上,是一个值得研究的问题。 在我国,关于蚊虫越冬调查以及越冬蚊虫生理的研究,报告得不多,冯兰洲在1937年曾就北京主要蚊种进行研究,观察到以卵越冬者有:仁川伊蚊Aedes(S)chemulpoensis、汉城伊蚊Aedes(F.)seoulensis、朝鲜伊蚊Aedes(F.)koreicus、多斑伊蚊Aedes(O.)maculatus等四种。以幼虫越冬有:帕氏按蚊 Anopheles(M.)pattoni、林氏按蚊Anopheles     

几种氧代丙酸化合物在诱捕白纹伊蚊中的应用

为了从氧代丙酸化合物中筛选出对白纹伊蚊Aedes albopictus具有良好引诱效果的化合物,采用陷阱诱捕法分别测定了丙酮酸（α-氧代丙酸）、3-甲氧基-2-甲基-3-氧代丙酸、3-(苄氧基)-3-氧代丙酸和3-氨基-3-氧代丙酸4种氧代丙酸化合物及丙酸对白纹伊蚊成虫的诱捕效果。结果表明,在供试的5种化合物中,α-氧代丙酸、3-甲氧基-2-甲基-3-氧代丙酸和3-(苄氧基)-3-氧代丙酸3种氧代丙酸化合物及丙酸的诱捕效果显著,同剂量的各化合物对白纹伊蚊的诱蚊效果依次是3-甲氧基-2-甲基-3-氧代丙酸>3-(苄氧基)-3-氧代丙酸>α-氧代丙酸=丙酸。相同质量α-氧代丙酸∶3-(苄氧基)-3-氧代丙酸=1∶1至1∶2的配方比,具有协同增效作用,平均累计诱捕量均显著优于单组分α-氧代丙酸、3-(苄氧基)-3-氧代丙酸和对照纯水（P<0.05）。其中最优配方比是α-氧代丙酸∶3-(苄氧基)-3-氧代丙酸=1∶2,平均累计诱捕量比单组分α-氧代丙酸增加45.45%,比单组分3-(苄氧基)-3-氧代丙酸增加32.33%和比对照纯水增加73.11%（P<0.05）。现场诱蚊试验结果表明,根据相似相溶原理将液体的氧代丙酸（α-氧代丙酸、3-甲氧基-2-甲基-3-氧代丙酸）分别与固体的氧代丙酸（3-(苄氧基)-3-氧代丙酸）混配并结合陷阱诱捕器,能够显著提高对白纹伊蚊的持效性及诱捕数量（混合物60 d的累计诱蚊总数量是单组分的1.28~2.15倍）。研究结果为进一步开发适用于家居办公环境中使用的诱蚊剂提供了研究基础。     

Complexation of Lead by Bermuda Grass Root Exudates in Aqueous Media

Exudates produced from Bermuda grass roots were collected in deionized water from sterilized Bermuda grass sod at 3-day intervals over a period of 15 days. Exudates were analyzed for total organic carbon, and characterized via Fourier Transform Infrared Spectroscopy. Exudate samples were adjusted to pH values of 4.5, 6.5, and 7.5, amended with lead and quantified for soluble and complexed lead via Inductively Coupled Plasma—Optical Emission Spectrometry. Data obtained from total organic carbon measurements indicated compositional changes in Bermuda grass root exudates as organic carbon concentrations increased over time. Analysis of the infrared spectroscopy data indicated that carboxylic acids and amine functional groups were present in root exudates. Also, the ability of root-exuded compounds to solubilize lead in aqueous media was demonstrated as exudate samples dissolved an average of 60% more lead than deionized water. At pH values 4.5 and 7.5, lead complexation by Bermuda grass root exudates increased with decreasing molecular weight size fractions, while an opposite trend was observed at pH 6.5. Results from this study demonstrated the ability of Bermuda grass root exudates to complex lead in aqueous media.     

狗牙根白化病植原体16S rDNA序列

[目的]狗牙根(草坪草的一种)白化病是狗牙根的一种重要病害,在全世界均有分布.为了确定中国大陆狗牙根白化病病原,进一步与世界其他地区的病原相比有无特异性.[方法]采用植原体16S rDNA PCR扩增、序列分析、Southern分子杂交等技术对狗牙根健康植株及白化病患病植株进行研究.[结果]仅白化病植株扩增获得1.3 kb的特异片段,序列分析表明特异片段与CandidatusPhytoplasm Cynodontis有99%同源性.Southern杂交有特异条带,大小在预期范围之内.证实了在中国大陆发生的狗牙根健株型白化病病原含有植原体.[结论]大陆狗牙根白化病病原中含有植原体,为该病病原的进一步鉴定与防治奠定了基础.     

Influence of Bacillus thuringiensis var. israelensis on oviposition of Aedes albopictus (Skuse).

The effect of Bacillus thuringiensis var israelensis (B.t.i.) on the oviposition behavior of Aedes albopictus was evaluated in the field and laboratory in Clemson, SC, U.S.A. In the field, water taken from containers in which mosquito larvae were reared (conditioned water) was placed in 16 containers. Eight containers received 50 jld of B.t.i., and eight with water only were kept as controls. In the laboratory, field-collected females of Ae. albopictus were placed in rearing chambers and provided two containers for oviposition, one with 50 microl of B.t.i and one a control with water only. Eight cage experiments were conducted, five using filtered tap water and three with conditioned water. In the field over the 13 trials, more eggs were laid in the containers with B.t.i. although no significant difference was found in the number of eggs between the treatment and controls over 72 h. In the laboratory, more eggs were laid in the containers with B.t.i. versus the controls. The containers had filtered tap water and B.t.i. had significantly more eggs laid in them compared to the controls.     

PRIMARY AND SECONDARY EFFECTS OF WATER CONTENT ON THE SPECTRAL REFLECTANCE OF LEAVES

Leaves of six species selected to represent a broad range in internal structure were collected in the field and studied in the laboratory to determine primary and secondary effects of water content on leaf spectral reflectance. Primary effects were those that resulted solely from the radiative properties of water. Secondary effects were those that could not be explained solely by these properties. Decreased leaf water content generally increased reflectance throughout the 400-2,500-nm wavelength range. For the aquatics Eichhornia crassippes and Nuphar luteum, the broadleaved trees Liquidambar styraciflua and Magnolia grandiflora, the cane-grass Arundinaria tecta, and the needle-leaved Pinus taeda, the sensitivity of reflectance to water content was greatest in the water absorption bands near 1,450, 1,940, and 2,500 nm. Sensitivity maxima occurred also between 400 and 720 nm, indicating secondary effects that resulted from decreased absorption by pigments. Secondary effects of water content on reflectance that were largely wavelength-independent, together with any wavelength-independent effects of leaf internal structure, were far less significant than primary and secondary effects resulting from decreased absorption by water and pigments, respectively.     

Accidental importation of the mosquito Aedes albopictus into the Netherlands: a survey of mosquito distribution and the presence of dengue virus

Abstract.  In the summer of 2005, the Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae) was found for the first time in the Netherlands. It was collected on the premises of several horticultural companies that import the ornamental plant Dracaena sanderiana (Sparagalus: Dracaenaceae [Agavaceae]), known as Lucky bamboo, from southern China, an area endemic for this mosquito species and for arboviruses transmitted by this vector. Here we report the results of a 1-year survey of the distribution and vector status of Ae. albopictus in Lucky bamboo nurseries in the Netherlands (July 2006–June 2007). As it had been established previously that the presence of this species was linked to the import of Lucky bamboo, the survey was conducted only on sites owned by relevant import companies. In total, 569 adult Ae. albopictus were collected with mosquito traps from 15 of the 17 (88%) glasshouses used by Lucky bamboo importers, none of which were found to be infected with dengue virus. On two occasions there was evidence that Ae. albopictus had escaped from the glasshouses, but, overall, there was no evidence that a population had become established in the greenhouses or elsewhere.     

四种园林植物的热值与养分特征

测定了蔷薇科植物美人梅、樱花和木兰科植物白玉兰、广玉兰不同组分的热值、养分和灰分含量, 探讨4种植物不同发育阶段根系、枝干和叶等器官的热值分配特征及其影响因子. 结果表明: 4种植物不同组分干质量热值和去灰分热值在17.02～21.93 kJ·g^-1和18.42～22.57 kJ·g^-1之间; 叶片和细根具有较高的干质量热值和去灰分热值, 去灰分热值随着根系和茎干（枝）的发育呈减小趋势. 美人梅和樱花的干质量热值和去灰分热值总体上高于白玉兰和广玉兰. 细根干质量热值和去灰分热值与其养分和灰分含量呈极显著相关(P<0.01). 随着根系的发育, 干质量热值和去灰分热值与有机碳含量的相关性逐渐降低, 不同器官干质量热值与全氮含量相关性最强.     

Evaluation by electron microscopy and anaerobic culture of types of rumen bacteria associated with digestion of forage cell walls.

Different morphological types of rumen bacteria which degraded cell walls of forage grasses with various in vitro digestibilities were evaluated with electron microscopy. The majority of these bacteria (i.e., about 70% or more) consisted of two distinct types: (i) encapsulated cocci and (ii) irregularly shaped bacteria, resembling major fiber digesters found in the rumen. Each type was capable of degrading structurally intact cell walls. Differences (P less than or equal to 0.02) in the percent ratio of encapsulated cocci to irregularly shaped bacteria were observed between Bermuda grass and fescue; the ratio of encapsulated cocci to irregularly shaped bacteria between Bermuda grass and orchard grass was similar and variations were high. The proportion of irregularly shaped bacteria usually increased with increased time of digestion. Differences (P greater than 0.1) were not found in the percentage ratio of encapsulated cocci to irregularly shaped bacteria attached to specific tissue types in either Bermuda grass or fescue. However, encapsulated cocci tended to be more prevalent on sclerenchyma than other tissues in Bermuda grass, but less prevalent on sclerenchyma than other tissues in fescue. Transmission electron microscopy of tissue digestion of rapidly degraded orchard grass blades revealed that mesophyll, parenchyma bundle sheath, and parts of the epidermal cell wall apparently were degraded without direct attachment of bacteria although bacteria were near the cell walls undergoing digestion. Anaerobic growth studies showed that the total culturable bacteria developing on medium 10 and media containing carbohydrates similar to those in forage cell walls (i.e., pectin, xylan, and cellobiose) were 80% higher from rumen bacterial populations adapted in vitro to cell walls of orchard grass compared to those from Bermuda grass; the number of colonies from the orchard grass-adapted population was significantly (P less than or equal to 0.05) greater on the medium containing xylan. Filter paper tests showed that the cellulolytic activity of populations adapted to fescue was greater than that of orchard grass or Bermuda grass.     

Bermuda grass as feedstock for biofuel production: a review

Bermuda grass is a promising feedstock for the production of fuel ethanol in the Southern United States. This paper presents a review of the significant amount of research on the conversion of Bermuda grass to ethanol and a brief discussion on the factors affecting the biomass production in the field. The biggest challenge of biomass conversion comes from the recalcitrance of lignocellulose. A variety of chemical, physico-chemical, and biological pretreatment methods have been investigated to improve the digestibility of Bermuda grass with encouraging results reported. The subsequent enzymatic hydrolysis and fermentation steps have also been extensively studied and effectively optimized. It is expected that the development of genetic engineering technologies for the grass and fermenting organisms has the potential to greatly improve the economic viability of Bermuda grass-based fuel ethanol production systems. Other energy applications of Bermuda grass include anaerobic digestion for biogas generation and pyrolysis for syngas production.     

干旱胁迫下活化水灌溉对大豆生长特征的影响

为了解在不同干旱条件下活化水灌溉对大豆生长特征的影响,探究活化水灌溉对大豆生长的影响机制。采用室内基质栽培大豆试验,在基质最大持水量(80%含水量)的95%～100%、75%～85%、55%～65%和35%～45% 4个水分条件下,分别用自来水、磁化水、增氧水和先磁化再增氧4种水灌溉,研究活化水对大豆苗期生长特征的影响。结果表明: 经过30 d的生长后,35%～45%重度干旱条件下磁化水灌溉的总生物量、叶面积、根冠比和根长与自来水灌溉相比分别增加了67.6%、23.5%、84.6%和122.8%,磁化增氧水灌溉分别增加了70.8%、24.0%、61.9%和162.3%,对叶绿素含量无显著影响;其余处理上述指标与自来水相比略有下降。表明重度干旱条件下,磁化水灌溉可以有效促进大豆根系生长、提高根冠比,提高大豆的水分利用效率,缓解干旱胁迫带来的负面效应。