植物保护剂保卫德对小菜蛾种群控制效应评价

室内外试验表明,植物保护剂保卫德（BIOACT－T35）对小菜蛾种群具有较好的控制效应,其显的控制机理主要表现在对成虫产卵的忌避作用和对幼虫的拒食作用。保卫德10．00ml／L处理对成虫的忌避率为81．43％,对幼虫的选择和非选择性拒食率为96．32％和93．17％,小菜蛾种群趋势指数I值由对照的18．2840降为1．9492,干扰作用控制指数为0．1066。     

非嗜食植物次生物质对小菜蛾产卵驱避和拒食作用的研究

基于植物与昆虫的协同进化理论,利用25科37种小菜蛾非嗜食植物的茎、叶、花或根的乙醇提取物,研究其对小菜蛾成虫的产卵驱避作用和对幼虫的拒食作用。结果表明,供试植物提取物对小菜蛾有不同程度的产卵驱避和拒食效果,羊蹄甲、细叶桉、飞扬草、假连翘、花椒、荷花玉兰、烟草的乙醇提取物对小菜蛾成虫产卵有较好的驱避效果,驱避率均达80％以上,一品红、构树、艾蒿、茶枯、垂柳、飞扬草、羊蹄甲、狗尾草的乙醇提取物对小菜蛾幼虫有较好的拒食作用,48h的拒食率达80％以上。     

爵床的甲醇提取物对小菜蛾的生物活性作用

为探明爵床(Justicia procumbens)甲醇提取物对小菜蛾的生物活性,采用室内生测法测定了爵床甲醇提取物对小菜蛾的触杀、拒食、胃毒、生长发育抑制和产卵忌避作用。结果表明,爵床甲醇提取物对小菜蛾幼虫具有较强的触杀、拒食、胃毒和生长发育抑制活性,对小菜蛾成虫具有较强的产卵忌避活性。在触杀试验中,药后1、2 d和3 d爵床甲醇提取物对小菜蛾3龄幼虫的致死中浓度(LC50)分别为5.17、4.05和3.06 mg/m L;在拒食试验中,药后1 d和2 d提取物对3龄幼虫的选择性拒食中浓度(AFC50)分别为2.64和3.13 mg/m L,药后1 d和2 d提取物对3龄幼虫的非选择性拒食中浓度(AFC50)分别为3.70、4.54 mg/m L;在胃毒试验中,药后4、5、6 d和7 d提取物对3龄幼虫的致死中浓度(LC50)分别为8.13、3.65、2.88、2.23 mg/m L;在生长发育抑制试验中,药后1 d和2 d提取物对3龄幼虫的抑制中浓度(IC50)分别为2.02、1.40 mg/m L;在产卵忌避试验中,药后1、2 d和3 d提取物对小菜蛾成虫的选择性产卵忌避中浓度(AOC50)分别为2.61、3.66、4.58 mg/m L,药后1、2和3 d提取物对小菜蛾成虫的非选择性产卵忌避中浓度(AOC50)分别为3.19、4.52、5.65 mg/m L。由此证实,爵床提取物对小菜蛾具有显著的毒杀活性,具有开发为新型高效、低毒植物源农药的潜在价值。     

辣椒碱对小菜蛾的驱避活性及其体内谷胱甘肽-S-转移酶和Na+，K+-ATP酶活性的影响

采用常规生测方法和酶活力测定方法,初步研究了辣椒碱对小菜蛾Plutella xylostella L.的产卵忌避和拒食作用,及其对小菜蛾体内谷胱甘肽-S-转移酶、Na⁺,K⁺-ATP酶活性的影响,以期阐明辣椒碱对害虫的作用机制。结果表明,辣椒碱对小菜蛾表现出较强的产卵忌避活性和拒食活性。在6.25×10⁴ mg/L浓度下,处理24 h辣椒碱对小菜蛾的非选择性产卵忌避率达96.55%,选择性产卵忌避率为84.30%;在相同浓度下,处理48 h辣椒碱对小菜蛾的非选择性拒食率达81.47%,选择性拒食率为69.69%。 另外,经1.25×10⁵ mg/L辣椒碱不同时间处理后,小菜蛾体内的谷胱甘肽-S-转移酶酶活力和Na⁺,K⁺-ATP酶活力与对照相比均产生了波动,处理18 h时小菜蛾体内GSTs活力最高,为152.01 U·mg^-1pro·min^-1,处理1 h时小菜蛾体内Na⁺,K⁺-ATP酶活力最高,为19.99 U·mg^-1pro·min^-1。结果说明辣椒碱能够影响小菜蛾产卵和取食行为,并且对其体内的酶系也产生了影响。     

番茄抽提物对小菜蛾的忌避,拒食及抑制产卵作用

在自然变温条件下,研究了番茄抽提物对小菜蛾成虫的忌避、幼虫的拒食作用及成虫繁殖力的影响。试验表明：番茄抽提物对小菜蛾成虫具有很强的忌避作用;用番茄抽提物处理过的包菜叶饲喂小菜蛾幼虫,其拒食率达５３％;番茄提物对小菜蛾成虫产卵也有明显抑制作用,产卵量下降６０％;番茄与包菜间种能明显地抑制小菜蛾种群数量的增长。其种群可下降５０％以上。     

鱼藤酮对松墨天牛产卵和取食行为的影响

为探索松墨天牛防治的新方法,实验了鱼藤酮对松墨天牛产卵和取食行为的影响及鱼藤酮对松墨天牛5龄幼虫的触杀作用。结果表明,鱼藤酮对松墨天牛具有显著的产卵忌避作用和成虫取食的干扰作用。产卵忌避作用和拒食作用随鱼藤酮浓度的增大而增强,处理浓度为1 000 mg/L时,鱼藤酮对成虫的产卵忌避率为75.63 %,处理后12 h松墨天牛的选择性和非选择性拒食率分别为72.91%和69.50%。鱼藤酮对松墨天牛5龄幼虫的触杀作用不明显。因此,利用鱼藤酮防治松墨天牛,一方面可以通过抑制其取食减少松材线虫的传播;另一方面通过忌避产卵可减少下代虫口。     

印楝素乳油x对-小菜蛾种群的控制作用

通过室内外系统试验探讨了印楝素乳油对小菜蛾Plutella xylostella种群的控制作用.结果表明,其控制作用主要表现在对成虫产卵的显著忌避作用、对幼虫的拒食作用以及对生长发育的影响和减少幼虫危害力等方面.印楝素乳油0.005 mL/L处理对成虫的忌避率为78.3%,对幼虫的选择性和非选择性拒食率分别为71.8%和62.9%,幼虫总取食量是对照的59.0%,使小菜蛾种群趋势指数(I值)降为2.4,干扰作用控制指数(1lpc)为0.1079.采用状态空间分析法就印楝素乳油施用后小菜蛾种群数量动态的模拟分析亦表明,其显著的控制作用表现在种群发展初期对成虫的忌避作用.     

印楝素乳油对小菜蛾种群的控制作用

通过室内外系统试验探讨了印楝素乳油对小菜蛾Plutella xylostella种群的控制作用。结果表明,其控制作用主要表现在对成虫产卵的显忌避作用。对幼虫的拒食作用以及对生长发育的影响和减少幼虫危害为等方面,印楝素乳油0.005mL/59.0%,使小菜蛾种群趋势指数（I值）降为2.4干扰作用控制指数（IIPC）为0.1079,采用状态空间分析法就印楝素乳油施用后小菜蛾种群数量动态的模拟分析亦表明,其显的控制作用表现在种群发展初期对成虫的忌避作用。     

茼蒿素类似物对小菜蛾生物活性

本文报道了茼蒿素类似物对小菜蛾的产卵忌避作用,对卵孵化的延缓作用、杀卵作用及对幼虫的毒杀作用。结果表明：茼蒿素类似物对小菜蛾具有一定的产卵忌避作用,在１０００μｇ／ｍｌ的浓度下,４号、８与、１２号和２０号化合物的产卵忌避作用分别为３９．９０％、５７．９０％、２５．５６％和４７．１４％;４种化合物均能延缓卵的卵化并具有一定的杀卵作用;８号、１２号和２０号化合物对小菜蛾２龄幼虫的ＬＣ５０分别为５８２．     

龙柏精油对小菜蛾的生物活性

龙柏精油对小菜蛾Plutella xylostella(L.)的室内生物活性测定结果表明,熏蒸作用是龙柏精油对小菜蛾的主要作用方式,熏蒸实验中当龙柏精油浓度为5.00 mg/L2、.50 mg/L时,处理后48 h小菜蛾2龄幼虫的校正死亡率分别为92.33%、80.29%。龙柏精油对小菜蛾具有较强的非选择性拒食作用和产卵忌避作用,但由于精油的挥发性效果不持久。当龙柏精油浓度为5.00 mg/L和2.50 mg/L时,24 h小菜蛾的产卵忌避率分别为80.45%和77.42%;而48 h则降为72.30%和61.79%。当龙柏精油浓度为5.00,2.50和1.25 mg/L时,24 h的非选择性拒食率分别为86.70,74.36和70.93%,48 h的非选择性拒食率分别降为82.36,71.40和60.40%。龙柏精油对小菜蛾具有一定的触杀活性,当龙柏精油浓度为5.00 mg/L时效果最好,24 h和48 h的校正死亡率分别为60.00%和76.67%。     

亚麻荠对小菜蛾幼虫取食和成虫行为反应的影响

亚麻荠是一种很少有害虫危害的油料作物。用室内生测和Y 型嗅觉仪研究了亚麻荠对小菜蛾Plutella xylostella幼虫取食和成虫行 为反应的影响。以甘蓝作对照,用亚麻荠叶片喂养的小菜蛾初孵幼虫3天后校正死亡率为79 .2%,显示了较强的致死作用;喂养小菜蛾3龄幼虫至化蛹,其存活率、化蛹率、蛹重及成 虫寿命都显著降低,表明亚麻荠对小菜蛾幼虫的生长发育有不利影响。在幼虫的取食选择实 验中,有甘蓝叶供选择时,小菜蛾幼虫不取食亚麻荠;在无可选择的情况下,小菜蛾幼虫也 取 食亚麻荠叶片,但取食量很小,与取食甘蓝叶的量相比,差异极显著。行为反应测试表明, 小菜蛾成虫对甘蓝和亚麻荠植株的挥发物都有明显的趋性反应,与对照（净化空气）相比, 差异极显著,而在甘蓝和亚麻荠之间无选择性。说明小菜蛾成虫对亚麻荠植株的挥发物具有 较强的定向反应。     

Antifeedant and Insecticidal Activity of Quassinoids against Diamondback Moth (Plutella xylostella)

The antifeedant and insecticidal activities of sixteen quassinoids against 3rd instar larvae of the diamondback moth (Plutella xylostella) were compared with those of known insect antifeedant chlordimeform (1), and the structure-activity relationship was discussed. The insecticidal activity of quassin (2) was higher than that of 1, although its antifeedant activity was nearly the same as that of the reference compound.     

Evaluation of insecticidal activity of a bacterial strain, <Emphasis Type="Italic">Serratia</Emphasis> sp. EML-SE1 against diamondback moth

To identify novel bioinsecticidal agents, a bacterial strain, Serratia sp. EML-SE1, was isolated from a dead larva of the lepidopteran diamondback moth (Plutella xylostella) collected from a cabbage field in Korea. In this study, the insecticidal activity of liquid cultures in Luria-Bertani broth (LBB) and nutrient broth (NB) of a bacterial strain, Serratia sp. EML-SE1 against thirty 3rd and 4th instar larvae of the diamondback moth was investigated on a Chinese cabbage leaf housed in a round plastic cage (Ø 10×6 cm). 72 h after spraying the cabbage leaf with LBB and NB cultures containing the bacterial strain, the mortalities of the larvae were determined to be 91.7% and 88.3%, respectively. In addition, the insecticidal activity on potted cabbage containing 14 leaves in a growth cage (165×83×124 cm) was found to be similar to that of the plastic cage experiment. The results of this study provided valuable information on the insecticidal activity of the liquid culture of a Serratia species against the diamondback moth.     

Preimaginal conditioning does not affect oviposition preference in the diamondback moth

Abstract.  1. In holometabolous insects, learning has been demonstrated in both larval and adult stages. Whether learning can be retained through metamorphosis from larva via pupa to adult has long been a subject of debate. The present study is designed to distinguish between preimaginal and imaginal conditioning in the diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae) using oviposition preference tests on females exposed to various types of learning experiences during immature and adult stages.
2. Cohorts of test insects were reared from egg to pupa on an artificial diet, or on one of two host plants, Chinese cabbage, Brassica campestris L. ssp. pekinensis , and common cabbage, Brassica oleracea L. var. capitata . The ensuing females reared on the three kinds of food showed similar oviposition preference between the two plants. A brief experience of the less preferred host, common cabbage, by adults slightly increased their preference for this plant.
3. Cohorts of test insects were reared from egg to pupa on an artificial diet with or without the addition of a neem-based oviposition deterrent (Neemix^® 4.5). Larval feeding experience did not alter oviposition response to the deterrent. However, emergence conditioning and early adult learning, achieved through experience of a residue of the deterrent carried over from the larval food on pupal cuticle and cocoons, altered oviposition preference significantly.
4. The combined results revealed no evidence of preimaginal conditioning in this insect but a strong effect of emergence conditioning and early adult learning on oviposition preference.     

Incorporation of Serine-3-14C into Sphingolipid by Rat Liver Particulate

Four semi-synthetic and fourteen quassinoids were tested for their antifeedant and insecticidal activity against 3rd instar larvae of the diamondback moth (Plutella xylostella). In this quassinoid series, isobrucein-B was the most potent compound in both assays. Chemical conversion of the methoxy and/or methylenedioxy groups in the A and C rings to hydroxy groups among these quassinoids resulted in decreased activity.     

Behavioural responses of diamondback moth Plutella xylostella (Lepidoptera: Plutellidae) to extracts derived from Melia azedarach and Azadirachta indica

The impact of three different doses of botanical insecticide derived from the syringa tree, Melia azedarach and the neem tree, Azadirachta indica was tested on the behaviour of the diamondback moth, Plutella xylostella (Linnaeus). Both botanical insecticides had a significant impact on larval behaviour. At higher doses the extracts showed feeding deterrent activity, with larvae preferring the untreated sides of cabbage leaves and consuming less of the treated half of cabbage leaves. The botanical insecticides had less of an effect on the oviposition behaviour of P. xylostella moths. In laboratory and glasshouse trials, significantly fewer eggs were oviposited on the plants that had been treated with syringa extracts. Therefore, the syringa extracts appear to have a repellent effect. In contrast, when exposed to the neem extracts the moths did not discriminate between control plants and treated plants. Behavioural observation indicated that, despite the lower number of eggs oviposited on cabbage treated with syringa extracts, the moths chose cabbage treated with the highest dose of syringa more often than they chose control cabbage plants. Similar observations were found in cabbage plants treated with neem, moths chose the medium dose more often than they chose the control. Oviposition and feeding deterrent properties are important factors in pest control, and results from this study indicate that botanical insecticides have the potential to be incorporated into control programmes for P. xylostella in South Africa.     

不同虫态叉角厉蝽对草地贪夜蛾幼虫的室内捕食作用

为了明确叉角厉蝽 Eocanthecona furcellate (Wolff)对草地贪夜蛾 Spodoptera frugiperda (J.E.Smith)幼虫的控制作用,在实验室条件下测定了叉角厉蝽不同虫态对草地贪夜蛾不同龄期幼虫的捕食能力,研究了该蝽捕食功能反应、搜寻效应以及种内干扰作用。结果表明,叉角厉蝽3龄若虫、5龄若虫、成虫均可捕食草地贪夜蛾幼虫,总体呈现叉角厉蝽低龄若虫捕食草地贪夜蛾低龄幼虫的数量较多,高龄若虫和成虫捕食中间龄期幼虫数量较多的规律;叉角厉蝽3个虫态对草地贪夜蛾2~3龄幼虫的捕食功能反应均符合Holling II方程和HollingⅢ型功能反应新模型;5龄若虫对草地贪夜蛾2~3龄幼虫的捕食效能(a/Th)最强（214.0）、日最大捕食量(1/Th)最大（256.4头）。不同虫态叉角厉蝽的搜寻效应与草地贪夜蛾密度均呈负相关。建立了叉角厉蝽成虫密度、草地贪夜蛾4龄幼虫密度对捕食作用的干扰反应方程,干扰作用发生后该蝽的平均捕食量和捕食作用率均逐渐下降。本研究结果可为田间释放叉角厉蝽防治草地贪夜蛾提供依据。     

杠柳萃取物对小菜蛾幼虫的毒杀活性研究

以杠柳Periploca sepium Bunge的根为材料进行甲醇超声波提取,粗提物以水／氯仿（1：1,v／v）萃取获得杠柳根氯仿萃取物。测定了萃取物对小菜蛾Plutella xyllostellaL．3龄幼虫的胃毒和触杀活性。实验结果显示,在50μg／头剂量处理下24h和48h后,氯仿萃取物对小菜蛾3龄幼虫的胃毒死亡率分别为82．22％和92．59％,显著高于触杀死亡率58．89％和68．15％。这一结果表明,杠柳根中含有对小菜蛾幼虫具有较强胃毒作用的活性成分。