兴安落叶松诱导抗性对舞毒蛾幼虫解毒酶活性的影响

为了解不同诱导处理与落叶松诱导抗性及广食性昆虫舞毒蛾协同抗性之间的关系,以喷施茉莉酸甲酯、茉莉酮、舞毒蛾幼虫取食和松毛虫幼虫取食4种方法处理落叶松幼苗,检验舞毒蛾幼虫取食不同处理诱导的落叶松后,其中肠酸性磷酸酯酶(ACP)、碱性磷酸酯酶(AKP)、羧酸酯酶(CarE)、谷胱甘肽S-转移酶(GSTs)4种解毒酶活性随时间的变化趋势。结果表明:取食不同处理诱导的落叶松后,舞毒蛾幼虫酸性磷酸酯酶活性均显著低于对照;取食经舞毒蛾幼虫取食诱导的落叶松后,试虫中肠碱性磷酸酯酶活性先升高后降低,除此之外,取食其他3种处理诱导的落叶松后,幼虫中肠碱性磷酸酯酶活性均受到抑制;幼虫羧酸酯酶活性也都受到不同程度抑制,与对照相比差异极显著;幼虫谷胱甘肽S-转移酶的活性,取食茉莉酸甲酯和舞毒蛾幼虫取食处理的幼苗显著低于对照,而取食另外2种处理的幼苗显著高于对照。舞毒蛾幼虫取食诱导的植物抗性,可影响同一种群后续取食者的解毒机制,这是植物抗性和昆虫种内竞争的综合表现。茉莉酸甲酯作为一种外源植物激素,可诱导植物产生抗性,且有效抑制后续取食者的解毒作用,其作用强度与作用时间与舞毒蛾幼虫取食处理极为相似。茉莉酸甲酯可作为有效的植物诱导剂,在害虫...     

不同木麻黄无性系对木毒蛾幼虫生长发育的影响

研究了不同木麻黄无性系对木毒蛾幼虫生长发育的影响,并分析木毒蛾幼虫对不同木麻黄无性系的食物利用情况。结果表明:抗虫性较强的木麻黄无性系抑制木毒蛾幼虫的取食和生长发育,对木麻黄小枝取食量不超过0.38 g/(头·d),相对生长率不超过0.045 g/(g·d),化蛹率和羽化率分别不超过67%和60%,食物利用率和转化率明显较低,但近似消化率变化不明显;而感虫的无性系促进木毒蛾取食和生长,取食量均在0.43 g/(头·d)以上,相对生长率超过0.050 g/(g·d),化蛹率和羽化率分别在73%和66%以上,幼虫取食后,其食物利用率和转化率较高。     

树干涂毒环防治杨毒蛾

树干涂毒环防治杨毒蛾杨毒蛾属鳞翅目，夜蛾科，是危害杨树的主要害虫之一。每年４月下旬左右，杨树展叶时幼虫上树取食叶片，严重时可将整株叶片吃光。该虫有晚上上树取食，天明下树藏匿的习性，故可采用涂毒环的方法防治。药液配制：柴油１０～２０份，２０％速灭杀丁或...     

杉木害虫—(艹雀)茸毒蛾初步观察

在1982～1983年杉木害虫调查时发现(艹雀)茸毒蛾幼虫严重为害,经室内饲养获得四个完整发育虫态,现作一报导,供参考。 (艹雀)茸毒蛾属毒蛾科(Lymantriidae)茸毒蛾属(Dasychira)学名Dasychira melli Collenette分布浙江、江西、福建、广东、四川等省区。浙江境内在江山、昌化二地采获此虫,并在江山林场广渡分场进行饲养。幼虫取食杉木当年针叶为主,将叶食光或仅残留针叶     

泡桐茸毒蛾观察初报

泡桐茸毒蛾Dasychira sp.是危害泡桐的一种叶部害虫。1982—1984年该虫先后在河南省汝阳、临汝两县危害成灾,1987年又在偃师县大量发生,幼虫取食叶片,危害严重时,受害叶片仅剩叶柄。为摸清该虫的生物学特性,适时开展防治,作者对该虫进行了观察,现将观察结果初步整理如下。     

木麻黄毒蛾生活习性观察及其防治初报

木麻黄毒蛾(Lymantria Xylina Swinhoe)属鳞翅目毒蛾科。我县1971年开始发现。该虫主要为害木麻黄,以幼虫取食小校及嫩校表皮,也为害黑荆树、相思树、薄壳核桃、梧桐、柿、龙眼、荔枝等多种林果木的叶子,食性杂,蔓延快,为害严重,197     

刚竹毒蛾生物学特性及其防治

刚竹毒蛾,属鳞翅目毒蛾科,是竹子的主要害虫。该虫分布于四川、福建、江西、浙江、安徽等地,幼虫取食竹叶,成竹受害后严重影响发笋,并造成竹子材质变脆,降低竹材的使用价值。近几年在祁门县西武岭林场竹区时有发生,严重时将竹叶食尽,造成严重的损失。     

刺槐种子凝集素对舞毒蛾幼虫营养代谢影响的初步研究

在室内饲养舞毒蛾的条件下，用刺槐种子凝集素处理的叶片喂食舞毒蛾幼虫，对幼虫取食叶片后的死亡率、消化率、转化率和利用率进行了研究，结果表明：与对照相比，取食处理叶片的幼虫，有较高的死亡率，达59％；刺槐种子凝集素对舞毒蛾幼虫的营养代谢有较强的抑制作用。     

融合肽TAT-Helicokinin I对舞毒蛾生物活性研究

以美洲棉铃虫Helicoverpa zea利尿激肽Helicokinin I和穿膜肽TAT为基础合成融合肽TAT-Helicokinin I,并测试3种肽对舞毒蛾Lymantria dispar幼虫的注射活性;探究融合肽TAT-Helicokinin I和利尿激肽Helicokinin I经取食途径进入虫体后对舞毒蛾幼虫生长的影响。结果表明:TAT-Helicokinin I和Helicokinin I对舞毒蛾幼虫均表现出注射毒性,且TAT-Helicokinin I比Helicokinin I表现出更高的生物活性;60,600 pmol/头的剂量对舞毒蛾幼虫均表现出显著致死性,6 pmol/头的剂量对舞毒蛾幼虫生长无影响;Helicokinin I饲喂舞毒蛾幼虫未显现出毒性,而饲喂TAT-Helicokinin I对试虫生长表现出显著抑制作用。该研究证实TAT与Helicokinin I融合后能够降低昆虫消化道酶对利尿激肽Helicokinin I的降解。     

沙棘叶部新害虫——灰斑古毒蛾

灰斑古毒蛾Orgyia ericae Germar危害沙棘Hippophae rhamnoides Linn,取食叶片,严重时可造成树木死亡。该虫在我市一年发生2代,以卵在茧内越冬。初孵幼虫具有随风远距离传播的特性。该虫的发生和环境条件有密切关系。人工防治、化学防治都有很好的效果。天敌对其有一定的制约作用。     

Effects of prescribed fire on canopy foliar chemistry and suitability for an insect herbivore

We assessed the effects of a prescribed fire on the phytochemical characteristics and vigor of overstory chestnut oak, scarlet oak, and red maple, and measured the impact of potential changes on herbivore fitness. We compared foliar carbohydrates, tannins, nutrients, and fiber concentrations in foliage from burned and non-burned forest canopies. There were significant differences in most foliar characteristics between tree species. Total non-structural carbohydrate concentrations in scarlet oak and red maple foliage, and calcium levels in red maple foliage, were significantly lower in burned plots, but other phytochemical characteristics were largely unaffected by burning. Tree growth also varied with species. Burning increased chestnut oak relative growth, decreased scarlet oak growth, and had no affect on red maple growth. Scarlet oak and red maple foliage from burned and non-burned forest canopies were assayed for gypsy moth performance. Caterpillars fed foliage from scarlet oak, the preferred host, grew larger and developed more rapidly than did those fed red maple foliage. There were no significant burn treatment differences in caterpillar development within either tree species, suggesting that managers using prescribed fire to promote oak regeneration need not worry about enhancing forest stand susceptibility to gypsy moth. However, the fire in this study was of low to moderate intensity; more intense fires may alter foliar palatability.     

Untersuchungen zur überlebensfähigkeit und Entwicklung der Larven zweier Herkünfte des Schwammspinners Lymantria dispar L. (Lep.: Lymantriidae) in Abhängigkeit von der Fraßpflanze

The polyphagous gypsy moth (Lymantria dispar) is able to feed on about 400 different woody plant species. In general, oak species are preferred – on the other hand some other groups of plants are avoided on account of the presence of toxic substances. These unfavoured hosts are, for example, most of the Papilionaceae, like locust (Robinia pseudoacacia). We compared survival rate and development of two populations of different origin with long-term habituation to oak and locust, respectively. Larvae from the population habituated to oak proved unable to develop on locust food. There must be a lack of detoxification systems to modify the toxic alcaloids and flavenoids produced by Robinia pseudoacacia. On the other hand, larvae isolated from an locust stand were able to feed on oak leaves without problems in larval development or eclosion of adults. Gypsy moth larvae specialized on locust as host showed increased mortality (up to 27?%) in the early larval instars, but the surviving animals, especially female individuals, reached significantly higher pupal weights and showed better fecundity: 40?% higher egg numbers/egg mass compared to those feeding on oak. These results indicate that the gypsy moth population originating from the locust forest had achieved a high level of metabolic adaptation to this host plant and formed a 'biotype' of Lymantria dispar with optimal reproductive conditions in this special habitat.     

Monitoring the effects of gypsy moth defoliation on forest stand dynamics on Cape Cod,Massachusetts: Sampling intervals and appropriate interpretations

Gypsy moth (Lymantria dispar L.) outbreaks affect stand dynamics and successional patterns in pine–oak woodlands of North America's Atlantic coastal plain. Species-poor overstories are dominated by pitch pine (Pinus rigida), black oak (Quercus velutina) and white oak (Quercus alba). Both oaks are preferred food for gypsy moth, and white oak is the dominant late-successional species. We documented, over a 21-year period, the effects of gypsy moth defoliation on forest stand dynamics at Cape Cod National Seashore, Massachusetts. Our goal was to better understand the influence of gypsy moth defoliation on temporal changes in stand composition. Tree species abundance and frequency were measured in 16 stands with varying abundances of pitch pine and oak. Regression of 2-dimesional rates of change calculated from principal components analysis showed that gypsy moth significantly influenced stand dynamics and successional patterns between 1981 and 1992/1993. Defoliation was virtually absent in the 1990s, and analysis of 1992/1993–2002 rates of change showed topographic slope to be the most important factor influencing stand dynamics during this time. For the period 1981–2002 rates of change analysis failed to identify either factor as influencing changes in stand dynamics. We conclude that the 1980s defoliation events had a transitory effect on upland forest composition, but that there exists the potential for significant long-term impact due to recurrent defoliation episodes. Stand composition should be monitored at intervals which roughly correspond to the time it takes for stands to recover to disturbance events, in the case of those we sampled, approximately 10 years.     

Tree mortality risk of oak due to gypsy moth

We present prediction models for estimating tree mortality resulting from gypsy moth, Lymantria dispar, defoliation in mixed oak, Quercus sp., forests. These models differ from previous work by including defoliation as a factor in the analysis. Defoliation intensity, initial tree crown condition (crown vigour), crown position, and species grouping classes were highly significant in categorical analysis of variance for mortality. Heavy defoliation intensity was shown to have a strong, consistent influence in increasing the probability of tree mortality. Classification and Regression Tree (CART) analysis, a binomial decision tree procedure, was used to develop prediction models of mortality risk for use by forest managers. The best decision tree had 65 groups that correctly classified 75% of the live trees and 76% of the dead trees. Models were run separately by defoliation class and provided correct classifications between 63 and 78% of the trees. Forest land managers can use these models to assign probabilities of death for moderate and heavy defoliation intensity levels and compare predicted mortality to mortality of undefoliated trees to determine how gypsy moth defoliation will affect their stands. The probabilities can be used to develop marking guides Lased on projected defoliation levels for implementing silvicultural treatments to minimize gypsy moth effects in forest stands prior to infestation.     

Effect of Neem extract on Lymantria dispar L. (Lepidoptera: Lymantriidae) and Leptinotarsa decemlineata Say. (Coleoptera: Chrysomelidae)

High antifeedancy and low toxicity of the plant preparation Neem (azadirachtin), on the gypsy moth, Lymantria dispar L. larvae were proved under laboratory conditions. A high index of Neem antifeedancy was confirmed in all tested concentrations. Under laboratory conditions the Neem had satisfying antifeedancy on Leptinotarsa decemlineata Say third instar larvae too. Field experiments also proved that the foliage protective effect of Neem was very significant. Experiments showed that some antifeedants or repellents, such as Neem, should control olygophagous (L. decemlineata, Coleoptera) insects as well as very polyphagous insects such as L. dispar (Lepidoptera). As a biological, plant-derived preparation, Neem could be suitable for integrated pest management (IPM) programs, especially in small orchards, parks, and tree rows in urban environments and on small private gardens.     

四川省大邑县舞毒蛾天敌的研究*

１９９３年在大邑县共收集到舞毒蛾天敌３０种，其中寄生性昆虫１９种，捕食性昆虫９种，病毒和虫霉菌各１种。卵期平均寄生率为２７．０６％±０．５４％，大蛾卵跳小蜂是主要天敌。幼虫期天敌有病毒、斑痣悬茧蜂、毒蛾镶颚姬蜂和绒茧蜂等，平均杀死幼虫５１．５９％±６．４８％。蛹期主要天敌有寄蝇、广大腿小蜂和脊腿囊爪姬蜂等，平均寄生率达３２．９１％±２６．４０％。在舞毒蛾卵－蛹期，累计约有８７．６２％的个体被天敌致死。     

毒死蜱对舞毒蛾食物利用和解毒酶及AChE活性的影响

采用质量法和酶活性测定法研究了毒死蜱对舞毒蛾(Lymantria dispar)3龄幼虫食物利用的影响,并测定了其毒力及解毒酶、乙酰胆碱酯酶(AChE)的活性。用亚致死浓度(1.5 mg·L^-1)毒死蜱处理小黑杨叶片,饲喂舞毒蛾3龄幼虫,其幼虫生长率(RGR)、食物利用率(ECI)和食物转化率(ECD)均显著低于对照,而近似消化率(AD)显著高于对照,相对取食量(RCR)处理和对照间差异不显著。毒死蜱对舞毒蛾幼虫24 h致死中浓度(LC₅₀)为5.86 mg·L^-1,其毒力低于三氟氯氰菊酯而高于氧化乐果。毒死蜱对舞毒蛾3龄幼虫体内羧酸酯酶(CarE)、谷胱甘肽S-转移酶(GSTs)和AChE均有抑制作用,抑制程度为CarE＞AChE＞GSTs。毒死蜱通过影响舞毒蛾食物利用和抑制酶活性而表现出杀虫活性,为一种有效防治舞毒蛾的有机磷杀虫剂。     

Effect of treatment using nuclear polyhedrosis virus on Lymantria dispar in field experiments in central Slovakia

Two strains of the nuclear polyhedrosis virus of the gypsy moth, Lymantria dispar, are compared in field applications on experimental plots. With dosages 2 × 10¹¹–10¹² PIB ha⁻¹ received, corrected mortalities of larvae varied from 70% to 92%. At the same time, natural mortality of untreated populations ranged form 27% to 55% at the peak of the outbreak. The total reduction with ‘Gypchek’ the U.S. commercial formulation, reached 95%, compared with 93% after application of non-formulated material of a local strain under identical conditions. The American strain of NPV of the gypsy moth does not differ significantly in its effect from the local NPV on European populations of the gypsy moth.     

γ射线辐照对舞毒蛾幼虫DNA作用的研究

应用γ射线辐照灭虫方法防治病虫害,可以避免化学防治的药物残留问题。采用不同剂量γ射线辐照舞毒蛾幼虫,再用经典的琼脂糖凝胶电泳检测DNA的损伤程度,研究γ射线对舞毒蛾幼虫细胞的生物学效应。实验结果表明：γ射线照射后的幼虫细胞核DNA片段的大小与辐照剂量之间有明显的剂量效应关系,这为物理灭虫提供理论数据。     

Element accumulation patterns of deciduous and evergreen tree seedlings on acid soils: implications for sensitivity to manganese toxicity

Foliar nutrient imbalances, including the hyperaccumulation of manganese (Mn), are correlated with symptoms of declining health in sensitive tree species growing on acidic forest soils. The objectives of this study were to: (1) compare foliar nutrient accumulation patterns of six deciduous (sugar maple (Acer saccharum Marsh.), red maple (Acer rubrum L.), red oak (Quercus rubra L.), white oak (Quercus alba L.), black cherry (Prunus serotina Ehrh.) and white ash (Fraxinus americana L.)) and three evergreen (eastern hemlock (Tsuga canadensis L.), white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss.)) tree species growing on acidic forest soils; and (2) examine how leaf phenology and other traits that distinguish evergreen and deciduous tree species influence foliar Mn accumulation rates and sensitivity to excess Mn. For the first objective, leaf samples of seedlings from five acidic, non-glaciated field sites on Pennsylvania's Allegheny Plateau were collected and analyzed for leaf element concentrations. In a second study, we examined growth and photosynthetic responses of seedlings exposed to excess Mn in sand culture. In field samples, Mn in deciduous foliage hyperaccumulated to concentrations more than twice as high as those found in evergreen needles. Among species, sugar maple was the most sensitive to excess Mn based on growth and photosynthetic measurements. Photosynthesis in red maple and red oak was also sensitive to excess Mn, whereas white oak, black cherry, white ash and the three evergreen species were tolerant of excess Mn. Among the nine species, relative rates of photosynthesis were negatively correlated with foliar Mn concentrations, suggesting that photosynthetic sensitivity to Mn is a function of its rate of accumulation in seedling foliage.