植物精油对荔枝蒂蛀虫的产卵驱避效果

在室内采用非选择性和选择性两种试验方法,测定了14种非寄主植物精油对荔枝蒂蛀虫的产卵驱避效果.结果表明,香紫苏油、肉桂油和香茅油对荔枝蒂蛀虫有很好的产卵驱避效果,其非选择性产卵驱避率(ODRn)达90%以上;而选择性产卵驱避率(ODR.)达80%以上.留兰香油对荔枝蒂蛀虫也有较好的产卵驱避效果,其ODRn和ODR.分别为89.19%和73.30%.     

烟碱对假眼小绿叶蝉和茶尺蠖的忌避(拒食)活性

【目的】尼古丁是茄科植物的重要生物碱,本文首次确定了硫酸烟碱对假眼小绿叶蝉Empoasca vitis G?the的驱避作用和田间防效,以及不同浓度硫酸烟碱对茶尺蠖Ectropis obliqua Prout的拒食作用。【方法】使用Y形嗅觉仪和T形观测室研究了假眼小绿叶蝉对硫酸烟碱的行为反应,使用叶碟法测试了硫酸烟碱对茶尺蠖的拒食作用。【结果】硫酸烟碱600倍稀释液和800倍稀释液处理茶梢分别对叶蝉若虫的寄主选择行为和雌成虫的产卵具有显著的驱避作用;田间喷施硫酸烟碱对假眼小绿叶蝉的防治效果较好。此外,硫酸烟碱对茶尺蠖幼虫具有拒食作用,并且拒食作用随着取食时间的延长而增强,取食8 d以后,死亡率显著高于对照。【结论】本研究结果为开发茶树害虫的植物源忌避(拒食)剂提供一定的科学参考。     

茶丽纹象甲为害诱导的茶树防御反应分析

基于转录组测序,获得了茶树新梢叶片被茶丽纹象甲为害前后的差异基因表达谱,并从信号监测与转导、转录因子、次生代谢物生成等方面分析了相关基因的表达变化情况,为进一步研究茶丽纹象甲为害诱导的茶树防御机制奠定基础。结果表明:(1)茶丽纹象甲为害茶树新梢叶片后共检测到显著上调表达基因309个,显著下调表达基因297个,这些显著差异表达基因共分成23类。(2)检测到信号监测与转导过程中合计17个单基因上调表达2.0～2.8倍,包括富含亮氨酸重复序列的类受体蛋白激酶基因、促分裂原活化蛋白激酶级联信号系统蛋白激酶基因、茉莉酸信号通路基因、钙离子信号基因、水杨酸代谢通路基因;检测到21个转录因子单基因上调表达1.8～2.8倍,包括bHLH、WRKY、bZIP、MYB、UAF等转录因子;检测到苯丙类、类黄酮及萜类物质代谢过程中合计8个单基因上调表达2.1～2.5倍,包括苯丙酮酸互变异构酶基因、肉桂酰辅酶A还原酶基因、二氢黄酮醇还原酶基因、花色素还原酶基因、法尼基二磷酸合成酶基因、法尼醇脱氢酶基因。研究认为,茶丽纹象甲为害诱导信号转导、转录因子及次生代谢过程中的基因增量表达以机械损伤作用为主,昆虫口腔分泌物对这些基因的诱导表达具有协同促进作用。     

四种植物精油对黑翅土白蚁触杀和驱避作用

为筛选出高效防治黑翅土白蚁的天然植物精油,减少有机合成农药的使用,该文研究了大蒜精油、肉桂油、丁香油和印楝素油四种植物精油对黑翅土白蚁的触杀效果和驱避作用。结果表明:大蒜精油、肉桂油和丁香油的浓度为5和10 mg·m L~(-1)时,处理2 h后,黑翅土白蚁的校正死亡率达100%,而相同浓度的印楝素油和对照处理的黑翅土白蚁校正死亡率低于5%。随着处理时间延长,浓度为1.25和2.5 mg·m L~(-1)的大蒜精油、肉桂油和丁香油处理6 h时,黑翅土白蚁的校正死亡率仍达100%,而此时对应的印楝素油和对照处理的黑翅土白蚁校正死亡率仅为10%,说明大蒜精油、肉桂油和丁香油对黑翅土白蚁具有较强的触杀效果。大蒜精油、丁香油和肉桂油在处理黑翅土白蚁2 h后LC_(50)值(半致死量)分别为1.572、1.05和1.03mg·m L~(-1),说明肉桂油对黑翅土白蚁的毒性相对最大,触杀效果最好。此外,10 mg·m L~(-1)的大蒜精油、肉桂油、丁香油和印楝素油的驱避试验表明,处理4、6、8和12 h后,大蒜精油、肉桂油和丁香油三精油处理区的黑翅土白蚁数均显著低于对照区的,驱避率总体93%,而对应的印楝素油的驱避率总体28.5%,表明大蒜精油、丁香油和肉桂油三种植物精油对黑翅土白蚁均有显著的驱避活性。综上可知,四种植物精油中大蒜精油、肉桂油和丁香油在防治黑翅土白蚁方面应用潜力很好,是开发绿色环保白蚁防治药剂的可选材料。     

7种寄主和非寄主植物气味对茶尺蠖成虫行为的调控效应

为探讨茶园生态系中植物气味对茶尺蠖成虫行为的影响,遂以茶园群落中7种常见植物新鲜嫩梢为味源,设1.5、5.0、7.5、10.0、15.0、20.0g和30.0g剂量,洁净空气为CK1,用Y型嗅觉仪对茶尺蠖成虫进行的剂量反应结果为:①剂量为1.5g时寄主薄荷诱得的成虫数与CK1的差异显著;随着剂量增加,其诱得成虫数呈抛物线式递减;剂量为30.0g时其诱得成虫数显著小于CK1。②随着剂量的加大,寄主迷迭香、茶叶和吸毒草诱得成虫数呈抛物线式递增,剂量分别为7.5、10.0g和15.0g、以及10.0g时,3种寄主分别与CK1引诱成虫数的差异显著;当剂量再加大,3种寄主皆表现驱避效应,当剂量为30.0g时迷迭香诱得成虫数显著小于CK1。③当剂量为1.5g时,寄主万寿菊呈微弱引诱效应,当剂量再增加时则呈微弱驱避效应且驱避效应增强,当剂量为30.0g时其诱得成虫数显著小于CK1。④当剂量为5.0g时,寄主碰碰香无引诱或驱避效应;剂量为7.5g时,碰碰香呈微弱引诱效应;当剂量再增加时则呈微弱驱避效应。⑤当剂量为5.0、7.5、10.0g,非寄主薰衣草未呈现引诱或驱避;当剂量再增加时则呈驱避效应;当剂量为30.0g时其诱得成虫数显著小于CK1。再以正己烷为溶剂,取新鲜薄荷、万寿菊、茶叶嫩梢榨汁,汁液浸泡橡皮头24h以汲取气味,制成诱芯,气味以当量计算,即1.5g薄荷/诱芯、0.75g薄荷/诱芯、1.5g万寿菊/诱芯、1.5g茶叶/诱芯;以正己烷浸泡橡皮头24h作为CK2。诱芯附于土黄色粘板组成诱捕器,连续7d诱捕第5代成虫,每日更换色板,均有较强诱捕效应;从1.5g薄荷/诱芯、CK2、1.5g万寿菊/诱芯、0.75g薄荷/诱芯至1.5g茶叶/诱芯,诱效显著增加;1.5g薄荷/诱芯的诱效显著弱于CK2。在第5代茶尺蠖幼虫期,取1/6hm2茶园各3个作为诱捕小区,同样大小的3块茶园作为CK3,查虫口基数。第5代发蛾盛期,在每诱捕小区均匀放置5种诱捕器各7只,连续诱捕7日,每日更换色板,第6代幼虫虫口校正下降率30%。由试验结果认为:植物气味有效调节茶尺蠖成虫行为,薄荷诱效稍强于茶叶,熏衣草有驱避效应。     

香茅精油对桔小实蝇产卵驱避作用及其化学成份分析

研究了香茅Cymbopogon nardus精油对桔小实蝇Bactrocera dorsalis (Hendel)的产卵驱避作用及其化学成分。结果表明,香茅精油对桔小实蝇产卵具有一定的驱避作用,不同浓度香茅精油处理芒果上的产卵量均显著低于对照,且随着香茅精油浓度的提高其产卵量逐渐减少,当浓度为10000μg/mL时,产卵驱避率为70.06%。采用气相色谱—质谱联用(GC-MS)技术分析了香茅精油的化学成份,结果发现该精油挥发物中含量较高的是3-蒈烯,香茅醛,香叶醇,香茅醇,柠檬烯。     

迷迭香植物精油对白纹伊蚊的驱避作用及其化学成分

应用水蒸气蒸溜法和超临界二氧化碳萃取法提取生长于云南的迷迭香茎叶植物精油,测试2种精油对白纹伊蚊Aedes albopictus Skuse的驱避作用,并利用GC/MS联用仪分析2种精油的化学成分。结果表明:超临界二氧化碳提取的迷迭香精油对白纹伊蚊的驱避时间是(5.82±1.13)h,达到国标驱避剂评价的B级标准。2种精油化学成分中都含有驱纹活性物质:柠檬烯、樟脑、Eucalyptol、(+)-4-Carene、1-methyl-4-(1-methyle thylidene)-cyclohexene、Beta-pinene等,且驱蚊活性成分在挥发油中占有较高比例,显示该植物精油在驱蚊方面有一定开发价值。     

三种植物提取物对菜青虫拒食活性的研究

本文测定了胡椒?葱?川楝子3种植物的石油醚和丙酮提取物对菜青虫3龄幼虫的拒食作用,结果表明,3种供试植物提取物5~40 mg/mL浓度处理24 h对菜青虫幼虫均有一定拒食作用,拒食率达到31.8%~99.8%。其中胡椒的石油醚提取液拒食作用最大,浓度为40 mg/mL的处理效果最好,拒食率达99.8%。总体上看,3种供试植物的石油醚提取物拒食作用大于丙酮提取物,24 h的拒食效果的优于48 h。     

植物提取物对B型烟粉虱的驱避效果研究

烟粉虱Bemisia tabaci是许多大田和温室作物的重要害虫。其食性杂,寄主广泛,除通过取食植物汁液造成为害外,还传播病毒和引起植物生理异常。本研究使用"Y"型嗅觉仪研究了6种植物精油和4种植物水提取物对B型烟粉虱成虫的驱避效果。结果表明:5μL的剂量下,6种精油的驱避指数(RI)为:山楂(60.09)花椒(48.53)霍香正气水(2.83)车前(-30.01)紫苏(-36.13)鱼腥草(-47.07);在α=0.05水平下,除霍香正气水外,其他处理均与空白对照有显著差异。山楂和花椒等量混合的精油的驱避指数为45.00;5 g/L的剂量下4种植物水提取物的驱避指数为:八角(41.28)大蒜(39.37)陈皮(39.09)花椒(35.45)。     

20种药用植物乙醇提取物对谷蠹的触杀和驱避活性

采用药膜法和滤纸药膜选择法,分别研究了20种药用植物乙醇提取物对谷蠹Rhizopertha dominica (Fab.)成虫的触杀和驱避活性。结果表明：触杀效果以葫芦巴Trigonelia foenum-graecum提取物的活性最强,蛇床子Cnidium monnieri和石菖蒲Acorus gramineus提取物次之。葫芦巴提取物0.39 mg/cm² 浓度处理48 h后对谷蠹的触杀死亡率为100%,处理72 h后对谷蠹的LD₅₀为19.94 μg/cm²。蛇床子和乌头Aconitum carmichaeli提取物对谷蠹成虫具有显著的驱避活性。蛇床子提取物同时具有较好的触杀和驱避活性。     

Repellency of essential oils against Nephotettix cincticeps: Laboratory and glasshouse assays

Four oils from Piper nigrum, Litsea cubeba, Zanthoxylum bungeanum and Curcuma longa were obtained by ethanol extraction. The repellency of these oils and two major compounds (linalool and piperine) was evaluated against female adult and third‐instar nymphs of the rice pest, Nephotettix cincticeps, under laboratory and glasshouse conditions. Paired‐choice and no‐choice assays were used for each treatment, with essential oils evaluated after 24 and 48 hr of exposure and chemical compounds evaluated after 12 and 24 hr of exposure. The potential effects of essential oils on activities of glutathione S tranferase (GST), carboxyl esterase (CarE) and acetyl cholinesterase (AchE) were also evaluated after 48 hr of exposure to leafhoppers. The constituents of the essential oils were determined using GC‐MS. The results showed that the major components in the oils were piperine (34.75%) for P. nigrum, 9,12‐octadecadienoic acid (Z,Z) (18.74%) for L. cubeba, ethanone, 1‐(2‐hydroxy‐4,6‐dimethoxyphenyl) (18.51%) for Z. bungeanum and turmerone (15.89%) for C. longa. In all cases, the essential oils repelled female adults and third‐instar nymphs of N. cincticeps. The repellency of the tested oils and chemicals compounds in the paired‐choice assay was higher than in the no‐choice assay. In all experimental conditions, P. nigrum and C. longa oils were the most and the least potent, respectively. Linalool was the best repellent among the single‐tested compounds under laboratory conditions. In the glasshouse study, the highest repellency was observed in the mixture of linalool and piperine. GST and CarE activities of leafhoppers were significantly enhanced by exposure to the four essentials oils; AchE activity increased significantly only in the P. nigrum and L. cubeba assays. Our results clearly indicate that the tested oils and chemical compounds are promising agents for developing plant‐based pesticides to control N. cincticeps.     

Biological activity of essential oils from seven Azorean plants against Pseudaletia unipuncta (Lepidoptera: Noctuidae)

Ten essential oils from seven Azorean plant species were evaluated for their insecticidal, ovicidal, feeding‐deterrence and growth inhibition activities against Pseudaletia unipuncta. The oils of Laurus azorica (leaves), and Juniperus brevifolia (leaves) showed strong moderate insecticidal effect on fourth‐instar larvae causing 93.3% and 46.7% mortality, respectively. Juniperus brevifolia (leaves), L. azorica (leaves), Persea indica (leaves), Hedychium gardnerianum (leaves) and Pittosporum undulatum (fruits and leaves) significantly affected the hatching of P. unipuncta eggs (<8% eclosions). Five oils showed significant feeding deterrent activities (L. azorica, 92.4%, J. brevifolia, 93.6%, P. undulatum leaves, 95.5% and fruits, 83.8% and H. gardnerianum, 88.2%). All of the essential oils tested, significantly inhibited the larval growth after 5 days of feeding on the treated diet. Essential oils from L. azorica and J. brevifolia were the most potent growth inhibitors among the oils tested, producing a decrease in the initial larva weight (?14.8 and ?14.5 mg, respectively). Our results indicate that L. azorica (leaves), J. brevifolia (leaves), P. indica (leaves), H. gardnerianum (leaves), and P. undulatum (leaves and fruits) can be exploited for the development of bioactive compounds as a new source of agrochemicals. Further emphasis on isolation and identification of active constituents can be useful to develop new environment‐friendly insect control agents.     

四种植物精油成分对枸杞棉蚜的生物活性

【目的】研究植物精油4种成分丁香酚(eugenol)、α-松油醇(α-terpineol)、肉桂油(cinnamon oil)和香茅油(citronella oil)对枸杞棉蚜Aphis gossypii的生物活性以及马来酸二乙酯和水杨酸乙酯对这些化合物对枸杞棉蚜毒力的影响,为无公害防治枸杞(Lycium spp.)害虫奠定科学基础。【方法】采用二项选择法测定上述4种精油成分(1%)对枸杞棉蚜无翅成蚜的驱避作用;玻璃管药膜法进行生物测定,评估这4种化合物及其与马来酸二乙酯或水杨酸乙酯的混合液对枸杞棉蚜成蚜的毒力;采用生物化学方法分析这些化合物处理后枸杞棉蚜成蚜乙酰胆碱酯酶(AChE)和三磷酸腺苷酶(ATPase)的离体活性。【结果】α-松油醇(1%)对枸杞棉蚜无翅成蚜的驱避作用明显,1, 2和3 h的驱避率分别为58.1%, 58.6%和55.7%; 3 h时测试的4种化合物对枸杞棉蚜成蚜的驱避率由大到小依次为α-松油醇>香茅油>肉桂油>丁香酚。丁香酚对枸杞棉蚜成蚜的毒杀作用最强,处理4 h时的LC₅₀值为0.48 mL/L,肉桂油、α-松油醇、香茅油对枸杞棉蚜成蚜的LC₅₀值分别为1.23, 6.24和11.97 mL/L。对枸杞棉蚜成蚜的生物测定结果表明,马来酸二乙酯对香茅油、肉桂油、丁香酚和α-松油醇的增效比分别为2.75, 2.86, 1.78和1.56;水杨酸乙酯对香茅油、肉桂油、丁香酚和α-松油醇的增效比分别为3.41, 2.67, 2.00和1.89。毒力比结果表明,所测定的4种化合物对枸杞棉蚜的毒力相差49.9倍,丁香酚与马来酸二乙酯或水杨酸乙酯的混合液对枸杞棉蚜的触杀毒力最高。4种精油成分对枸杞棉蚜成蚜AChE和ATPase活性有不同的作用,丁香酚对AChE活性的抑制作用最强,但对ATPase活性表现为低浓度促进,高浓度抑制。【结论】α-松油醇对枸杞棉蚜驱避作用最好;丁香酚、α-松油醇、肉桂油和香茅油这4种精油成分对枸杞棉蚜的毒力相差很大;丁香酚与马来酸二乙酯或水杨酸乙酯混合后对枸杞棉蚜的毒力提高,具有进一步开发应用的潜力;所测精油成分对枸杞棉蚜离体AChE和ATPase活性有一定抑制作用。     

Repellent action and contact toxicity mechanisms of the essential oil extracted from Chinese chive against Plutella xylostella larvae

Botanical pesticides play increasingly important roles in the control of agricultural pests. In this study, the insecticidal effects, specifically the repellent action and contact toxicity, of the essential oil extracted from Chinese chive (EOC) against Plutella xylostella larvae were confirmed. The mechanisms of repellent’s action were studied using electroantennograms (EAGs), and the effects on glutathione S‐transferase (GST), carboxylesterase (CarE), and acetyl cholinesterase were investigated after EOC treatments. The EOC affected the EAG results and inhibited the activities of GST and CarE in treated P. xylostella larvae, which could explain its insecticidal effects. And, four pyrazines showed greater repellent activities than that of the EOC, which was confirmed as the main active compounds of EOC.     

Antifungal activity of Juniperus essential oils against dermatophyte, Aspergillus and Candida strains

AIMS: The increasing resistance to antifungal compounds and the reduced number of available drugs led us to search therapeutic alternatives among aromatic plants and their essential oils, empirically used by antifungal proprieties. In this work the authors report on the antifungal activity of Juniperus essential oils (Juniperus communis ssp. alpina, J. oxycedrus ssp. oxycedrus and J. turbinata). METHODS AND RESULTS: Antifungal activity was evaluated by determination of MIC and MLC values, using a macrodilution method (NCCLS protocols), on clinical and type strains of Candida, Aspergillus and dermatophytes. The composition of the oils was ascertained by GC and GC/MS analysis. All essential oils inhibited test dermatophyte strains. The oil from leaves of J. oxycedrus ssp. oxycedrus is the most active, with MIC and MLC values ranging from 0.08-0.16 microl ml(-1) to 0.08-0.32 microl ml(-1), respectively. This oil is mainly composed of alpha-pinene (65.5%) and delta-3-carene (5.7%). CONCLUSIONS: J. oxycedrus ssp. oxycedrus leaf oil proved to be an emergent alternative as antifungal agent against dermatophyte strains. delta-3-Carene, was shown to be a fundamental compound for this activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Results support that essential oils or some of their constituents may be useful in the clinical management of fungal infections, justifying future clinical trials to validate their use as therapeutic alternatives for dermatophytosis.     

Repellent effectiveness of seven plant essential oils,sunflower oil and natural insecticides against horn flies on pastured dairy cows and heifers

Plant essential oils (basil, geranium, balsam fir, lavender, lemongrass, peppermint, pine and tea tree), mixed with either sunflower oil or ethyl alcohol, were applied at 5% concentrations to the sides of Holstein cattle. Pastured cattle treated with essential oils diluted in sunflower oil had less flies than the untreated control for a 24‐h period. However, the essential oil treatments were not significantly different than the carrier oil alone. Barn‐held heifers treated with essential oils and sunflower oil alone had significantly less flies than the untreated control for up to 8 h after treatment. Basil, geranium, lavender, lemongrass and peppermint repelled more flies than sunflower oil alone for a period ranging from 1.5 to 4 h after treatments applied to heifers. All essential oils repelled > 75% of the flies on the treated area for 6 and 8 h on pastured cows and indoor heifers, respectively. Geranium, lemongrass and peppermint stayed effective for a longer duration. Essential oils mixed with ethyl alcohol demonstrated less repellence than when mixed with the carrier oil. Safer's soap, natural pyrethrins without piperonyl butoxide and ethyl alcohol alone were not efficient at repelling flies. Essential oils could be formulated for use as fly repellents in livestock production.     

九种植物精油对腌肉及咸鱼害虫大头金蝇的杀卵作用

为开发腌肉和咸鱼害蝇的安全性杀卵剂,采用改进的浸卵法,进行了9种植物精油对大头金蝇的杀卵活性测定.结果表明:肉桂、丁香、八角茴香3种植物精油较为有效,它们的杀卵毒力(LC50)依次为0.428、1.605和2.489mg.ml-1,以肉桂油的毒力最强.通过GC/MC成分分析,从肉桂油检出22个成分,主成分桂皮醛占92.33%.合成桂皮醛(含量97.33%)的毒力为0.281mg.ml-1,略高于肉桂油,表明桂皮醛是肉桂油的主要杀卵活性成分,可替代肉桂油作为害蝇杀卵剂利用.     

Repellent effect of plant essential oils against Aedes albopictus.

Six essential oils: asteraceae oil, rutaceae oil, mentha piperta oil, carvacryl oil, citronella oil, and eucalyptus oil were tested for evaluation of their repellent effects against Aedes albopictus mosquitoes under laboratory conditions. Only citronella oil and eucalyptus oil were tested with human beings. There was considerable protection for mice. Carvacryl oil (7%) provided 100% protection for mice after 7 h. Eucalyptus oil (15%) gave protection to humans for least 3 h; the protection time was prolonged to 5 h after adding 5% vanillin. The mixture could be developed into a practical product after the field evaluation.     

Anti-biofilm activities of essential oils rich in carvacrol and thymol against Salmonella Enteritidis

The aim of the present study was to determine the bioactive compounds in four essential oils (EO’s) from Origanum heracleoticum, Origanum vulgare, Thymus vulgaris and Thymus serpyllum and to assess their antimicrobial and anti-biofilm activity against Salmonella Enteritidis. Strains were previously characterized depending on the expression of the extracellular matrix components cellulose and curli fimbriae as rdar (red, dry and rough) and bdar morphotype (brown, dry and rough). This study revealed that the EO’s and EOC’s (carvacrol and thymol) investigated showed inhibition of biofilm formation at sub-minimum inhibitory concentration. Comparing the efficacy of EO’s and EOC’s in the inhibition of biofilm formation between the strains with different morphotype (rdar and bdar) did not show a statistically significant difference. Results related to the effectiveness of EO’s and EOC’s (the essential oil components, carvacrol and thymol) on eradication of preformed 48?h old biofilms indicated that biofilm reduction occurred in a dose-dependent manner over time.     

植物精油对锈赤扁谷盗成虫熏蒸毒杀作用研究

为明确适用于防治锈赤扁谷盗的植物精油种类及其用量,本试验采用拌粮密闭熏蒸法,比较23种植物精油对锈赤扁谷盗成虫熏蒸毒杀活性差异,从中筛选出作用效果较好的精油种类进行熏蒸毒力测定。通过二次筛选结果表明,大蒜与芥末精油对锈赤扁谷盗成虫具有明显的熏蒸毒杀作用。进一步的毒力测试结果表明,在24 h、48 h、72 h处理时间下,大蒜精油对锈赤扁谷盗成虫的LC_(50)值分别为0.7827、0.7222、0.6478μL/L,而芥末精油在相同处理时间条件下的LC_(50)值分别为2.7581、2.6117及2.4619μL/L,大蒜精油对锈赤扁谷盗具有更强的熏蒸毒杀活性。