阿维菌素对黄胸散白蚁Reticulitermes speratus的毒效

在室内采用毒土法、滤纸法和毒土柱法测定了0.2%阿维菌素乳油对黄胸散白蚁的毒杀效果。 结果表明,阿维菌素对黄胸散白蚁的触杀作用速度较慢,在处理的96 h内,随时间推移毒性逐渐增强;黄胸散白蚁接触或取食药剂96 h后,其LC50值均低于20 mg/L;在供试条件下,用2.5 mg/L以上的浓度处理土壤,即能阻止黄胸散白蚁在土柱中的穿透,显示阿维菌素是一种值得进一步研究的白蚁预防药剂。     

三种有机磷农药对黑胸散白蚁毒杀作用的研究

在室内条件下(27±1℃;RH 60%～80%)测定了甲胺磷、乐斯本、甲基异柳磷对黑胸散白蚁的毒杀效果,结果表明:以上3种药剂均能在较低浓度下毒杀黑胸散白蚁.有效成分为2μg/ml的甲胺磷,2μg/ml的乐斯本,8μg/ml甲基异柳磷在处理后第一天黑胸散白蚁校正死亡率分别为91.2%、89.8%、97.8%.忌避性试验表明,以上3种药剂对黑胸散白蚁均无明显驱避作用.     

测试条件对啶虫脒毒土柱防白蚁效果的影响

将预防性杀白蚁药剂施在土壤中形成毒土层是当前控制白蚁为害的主要方法之一。以黄胸散白蚁Reticulitermes flaviceps为对象,啶虫脒为供试药剂,在室内进行毒土柱防白蚁效果测定。结果表明,供试白蚁数量和食物供应与否均对药效试验评价结果有较大影响,毒土柱长度对测试结果的影响与土壤中药剂浓度有关。当毒土柱长度达到10 cm时,所测结果即可反应药剂对白蚁的阻杀效果。用毒土柱法测定预防药剂防白蚁的效果时,建议用10 cm长的毒土柱,每个重复的白蚁数为工蚁100头,并用湿润滤纸片作为供试白蚁的食物和水源。     

丁硫克百威药土处理对台湾乳白蚁的驱避效果

在室内采用毒沙药膜法和毒土柱屏障法测定了丁硫克百威对台湾乳白蚁的触杀和驱避效果。结果表明,丁硫克百威药土在低浓度下对台湾乳白蚁无明显驱避性,处理土壤有效阻杀台湾乳白蚁的浓度为100 mg a.i.kg-1。该药值得进一步研究其残效期,以明确其用于防治农作物白蚁的可能性。     

β-石竹烯对黄胸散白蚁生物活性的研究

采用小滤纸片法、微量点滴法和塑料杯熏蒸法分别测定β-石竹烯对黄胸散白蚁的驱避、触杀和熏蒸作用。结果表明,在浓度分别为28、14、7 mg/mL时,毒杀后死亡率分别为45.83%、33.33%、29.17%,驱避率分别为96.70%、96.85%和92.22%;在受药量为5.6、2.8μg/头时,7 d后的校正死亡率分别为70.91%、65.45%,具有一定的触杀作用。但熏蒸作用效果不明显,与对照组无显著性差异。     

噻虫胺、甲氰菊酯药土处理对台湾乳白蚁的驱避效果

在室内采用毒沙药膜法和毒土柱屏障法测定了噻虫胺、甲氰菊酯对台湾乳白蚁Coptotermes formosanus Shiraki的触杀和驱避药效。结果表明,噻虫胺、甲氰菊酯毒沙药膜对台湾乳白蚁的LC50分别为3.01mg a.i.L-1和9.43 mg a.i.L-1。噻虫胺在低于4.5 mg a.i.kg-1的药土浓度下对台湾乳白蚁无明显驱避性,处理土壤有效阻杀台湾乳白蚁的浓度为5.37 mg a.i.kg-1;甲氰菊酯药土在低于20.0 mg a.i.kg-1的浓度下对台湾乳白蚁无明显驱避性或驱避性不明显,处理土壤有效驱避台湾乳白蚁的浓度为40.0 mg a.i.kg-1以上,表明噻虫胺是一种值得进一步研究的白蚁防治药剂。     

氯虫苯甲酰胺对黑胸散白蚁的室内毒力测定

通过采用室内毒力测定和驱避作用试验,测试氯虫苯甲酰胺对黑胸散白蚁的药效。结果表明,黑胸散白蚁对2.50 g/g以上的氯虫苯甲酰胺比较敏感,药后7d死亡率达到55%以上,传毒有效时间为7d~14d,且对该药剂无忌避作用。由此可初步看出,氯虫苯甲酰胺可作为一种新型的白蚁防治药物推广使用。     

三种杀虫剂亚致死剂量对黄胸散白蚁工蚁体内纤维素酶活性的影响

采用工蚁与浸药滤纸接触或取食含药松木粉的方法,测定了啶虫脒、氰戊菊酯和硼酸,在亚致死剂量下对黄胸散白蚁Reticulitermes flaviceps工蚁体内内切-β-1,4-葡聚糖酶(EG)和β-葡糖苷酶(BG)活性的影响。结果表明,用0.5、1.0和2.0 mg/L的啶虫脒处理黄胸散白蚁工蚁6~48 h,对其体内的EG和BG酶活性(处理48 h的除外)无显著影响;用0.5、1.0和2.0 mg/L的氰戊菊酯处理,可显著降低黄胸散白蚁工蚁体内的EG和BG酶活性;硼酸对黄胸散白蚁工蚁体内EG和BG酶活性的影响与处理浓度和处理时间有关。     

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%。     

16种植物乙醇提取物对桔全爪螨的生物活性测定

测定了16种植物乙醇提取物对桔全爪螨成螨的产卵忌避、驱避及毒杀生物活性。试验结果表明,海芋、山苍子及盐肤木茎叶的乙醇提取物有明显的产卵忌避作用,忌避率在96.43%以上;山苍子、枫香植物乙醇提取物对桔全爪螨成螨的驱避作用明显,驱避率在80%以上;山苍子、盐肤木茎叶、牡荆和幌伞枫提取物对桔全爪螨成螨的毒杀效果明显,在处理72h后,死亡率在92%以上。     

密褐褶孔菌Gloeophyllum trabeum对几种杀虫剂跟踪反应及对水坝白蚁诱杀效果的影响

测定了毒死蜱、氰戊菊酯、阿维菌素和氟虫腈等 4种杀虫剂与不同饵料混合后对家白蚁 Coptotermes formosanus和黄肢散白蚁 Reticulitermes flaviceps的口服毒性。在此基础上比较了各种饵料及由它们配成的毒饵对黄肢散白蚁的引诱力。结果表明 ,白蚁对甘蔗粉的喜好程度远超过对淀粉和松木粉。而受密褐褶孔菌 Gloeop hyllum trabeum侵染的甘蔗粉对白蚁的引诱力又远超过未受侵染的甘蔗粉。 4种杀虫剂中除氰戊菊酯外 ,另 3种与受侵染甘蔗粉制成的毒饵均能够在不损失杀白蚁活性的同时保留其对白蚁的引诱力。其中毒死蜱毒饵在为期30 d的水坝白蚁诱杀防治中取得最高 (6 6 .7% )的防治效果。     

Isolation and antifungal activity of kakuol, a propiophenone derivative from Asarum sieboldii rhizome

An antifungal substance active against Colletotrichum orbiculare (Berk & Mont) Arx was isolated from the methanol extracts of Asarum sieboldii (Miq) Maek rhizomes. High-resolution MS, NMR and UV spectral data confirmed that the antifungal substance is kakuol, 2-hydroxy-4,5-methylenedioxypropiophenone. Colletotrichum orbiculare was most sensitive to kakuol, with MIC of 10 microg ml(-1). Kakuol also completely inhibited the mycelial growth of Botrytis cinerea Pers ex Fr and Cladosporium cucumerinum Ellis & Arthur at 50 microg ml(-1) and 30 microg ml(-1), respectively. However, no antimicrobial activity was found against yeast and bacteria even at 100 microg ml(-1). Kakuol exhibited a protective activity against the development of anthracnose disease on cucumber plants. The control efficacy of kakuol against the anthracnose disease was in general somewhat less than that of the commercial fungicide chlorothalonil. This is the first report to demonstrate in vitro and in vivo antifungal activity of kakuol against C. orbiculare infection.     

Termite control with microencapsulated permethrin

Bait methods with microencapsulated active ingredients are proposed for controlling local populations of subterranean termites. The foraging workers will take up the microcapsules, transport them to the nest and pass them to their nestmates. In laboratory tests microencapsulated formulations of permethrin had lethal effects on Heterotermes indicola Wasman and Reticulitermes flavipes (Kollar) depending on the amount of active ingredient applied. The time interval between the application of the capsules and the occurrence of insecticidal effects could be modified by changing the wall thickness of the capsules. Tests revealed that the microcapsules were transmitted from donors to recipients by trophallaxis. Microencapsulated formulations from which the solvent used during the manufacturing process had been removed did not reveal any repellent effects in several tests.     

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。     

Juvenogens as potential agents in termite control: laboratory screening

Preliminary screening tests of eight juvenogens, fatty acid esters of two parent juvenoid alcohols, showed high juvenilizing effect in the termite Prorhinotermes simplex (Hagen). This effect is manifested by differentiation of termite workers into pre-soldiers, soldiers and/or soldier-intercastes ('soldiers'). Juvenogen 9 was tested with five other termite species: Zootermopsis angusticollis Hagen, Kalotermes flavicollis F, Cryptotermes declivis Tsai & Chen, Reticulitermes santonensis de Feytaud, and R flaviceps Oshima, and showed promising efficacy in force-feeding (FF) as well as in choice bioassays. In the economically important subterranean termites R santonensis and R flaviceps, after application of 0.5 mg ml(-1) in FF experiments ca 57 and 73%, respectively, of workers changed into soldiers. In Zootermopsis angusticollis application of 0.05 mg ml(-1) caused differentiation in 62% soldiers, and 57% soldiers differentiated after topical application of 1 microg of the tested compound per termite. Differentiation of excessive soldiers induced by a juvenile hormone-mimicking compound may cause disruption of the social structure and ultimately the death of the colony.     

The potential of botanical essential oils for insect pest control

Today,Insect Pest management (IPM) has to face up to the economic andecological consequences of the use of pest control measures.Fifty years of sustained struggle against harmful insects usingsynthetic and oil-derivative molecules has produced perversesecondary effects (mammalian toxicity, insect resistance andecological hazards). The diversification of the approachesinherent in IPM is necessary for better environmental protection.Among the alternative strategies, the use of plants, insecticidal allelochemicals appears to be promising. Aromatic plants, and their essential oils, are among the most efficient botanicals. Their activities are manifold. They induce fumigant and topical toxicity as well as antifeedant or repellent effects. They are toxic to adults but also inhibit reproduction. Although mechanisms depend on phytochemical patterns and are not yet well known, this widespread range of activities is more and more being considered for both industrial and household uses: essential oils are presently regarded as a new class of ecological products for controlling insect pests     

鸡粪沼液“新壮态”对韭菜迟眼蕈蚊的防控效果

为明确鸡粪沼液"新壮态"对韭菜迟眼蕈蚊的防控效果,于室内测定了其对韭菜迟眼蕈蚊卵和不同龄期幼虫的毒力,研究了其对韭菜迟眼蕈蚊雌成虫产卵和幼虫取食的驱避效果,并进行了田间药效试验。结果表明,"新壮态"0倍稀释液对韭菜迟眼蕈蚊卵有杀灭作用,死亡率达54.76%;对2~4龄幼虫均无直接毒杀作用;对雌成虫产卵和幼虫取食均有明显的驱避活性,对雌成虫产卵驱避率为74.75%,处理5 min后对幼虫的选择性和非选择性驱避率分别为78.62%和45.60%。田间药效试验表明,鸡粪沼液"新壮态"对韭菜迟眼蕈蚊有一定的控制作用,并明显增加韭菜产量。