Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabricius larvae exposed to nickel

Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabri- cius larvae was investigated by exposing S. litura larvae to the artificial diets amended with different doses of nickel for 3 generations. Nickel accumulations in the midgut of 6th instar larvae were detected by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and the induced metal- lothionein expression in the midgut of 5th and 6th instar larvae in 120 h were quantified using cad- mium-hemoglobin total saturation methods. The accumulated nickel in the midgut of the 6th instar larvae within a generation increased with the increase of the nickel doses in the treated diets and showed significant dose-dependence with the nickel doses in diets. Metallothioneins induced by nickel accumulated in the larval midgut also increased with nickel doses in diets and with the increasing stressing time in a generation. Results also suggested that the metallothionein expression was differ- ent with the time of S. litura larvae stressed by nickel.     

斜纹夜蛾幼虫不同组织对Zn2+积累作用的比较研究

 通过在人工饲料中添加不同质量分数的Zn²⁺,研究了植食性昆虫斜纹夜蛾Spodoptera litura Fabricius连续3代幼虫取食含不同质量分数Zn²⁺饲料后,第1和第3代6龄幼虫不同组织对Zn²⁺的积累作用。结果表明,经连续3个世代的胁迫,Zn²⁺在第1、3代斜纹夜蛾6龄幼虫脂肪体、表皮和中肠中的积累量随幼虫饲料中Zn²⁺ 质量分数及胁迫时间的增加而升高;中肠对Zn²⁺的积累作用最强,表皮次之,脂肪体最低。     

Effects of dietary nickel on detoxification enzyme activities in the midgut of <Emphasis Type="Italic">Spodoptera litura</Emphasis> Fabricius larvae

Nickel accumulated in midugt of Spodoptera litura Fabricius could induce the expression of metallothionein, one of the most important detoxification proteins in organisms. In the present study, the effects of dietary nickel on the activities of detoxification enzymes, such as carboxylesterase （CarE） and giutathione S-transferase （GST） in the midgut of S. litura larvae have been studied to get an understanding of the detoxification mechanisms of S. litura larvae to excessive nickel. Results showed that CarE activities in the midgut of the 5th instar larvae decreased at lower levels of nickel （≤5 mg/kg）, while increased with increasing nickel doses at higher levels of nickel （≥10 mg/kg） exposure in successive 3 generations. CarE activities of the 6th instar larvae were also characterized as inhibited at low levels of nickel exposure, and improved at higher levels in the 1st generation. CarE activities of 6th instar larvae in the 2nd and 3rd generations were all lower than that in control. However, GST activities in the midgut of the 5th and 6th instar larvae all increased with increasing nickel doses （1 --20 mg/kg） in diets.     

Effects of dietary nickel on apoptosis of hemocytes of Spodoptera litura (Fabricius) larvae

Effects of dietary nickel on apoptosis of hemocytes of the 6th instar larvae of Spodoptera litura Fabricius were evaluated using flow cytometry and Laser Scanning Confocal Microscopy (LSCM) by feeding S. litura larvae with artificial diets amended with different concentrations of nickel (1, 5, 10, 20 and 40 mg/kg) for 3 generations. Results showed that the hemocyte apoptosis rate of the 1st generation larvae increased with the increasing nickel concentrations in diet, and the apoptosis rate in the treatment with 40 mg/kg nickel was significantly higher than that in other treatments. In the 2nd generation, the highest hemocytes apoptosis rate was recorded in the treatment of the larvae exposed to 5 mg/kg nickel. The apoptosis rates in the larvae stressed by higher concentrations of nickel were lower than that in control. The apoptosis rates in the larvae exposed to nickel for 3 generations showed similar concentration-responses with that in the 2nd generation. However, the apoptosis rates in the larvae stressed with higher levels of nickel were all significantly inhibited in comparison with that in control. Therefore, effects of nickel stress on apoptosis of S. litura larvae were related with the nickel concentration in diets and the larval generations that were stressed by nickel.     

寄主植物和试虫龄期对斜纹夜蛾药剂敏感性的影响

采用浸叶法测定了取食芋、甘薯、白菜和空心菜4种不同寄主植物的斜纹夜蛾（Spodoptera litura）4龄幼虫对高效氯氟氰菊酯、毒死蜱、溴虫腈、甲氨基阿维菌素苯甲酸盐和氟虫腈的敏感性,比较了不同龄期幼虫对药剂的敏感性差异。结果表明：在取食的4种寄主植物中,斜纹夜蛾4龄幼虫对以上5种药剂敏感性最高的均为甘薯,敏感性最低的均为芋,取食白菜和空心菜的幼虫对药剂的敏感性无明显差异;不同龄期斜纹夜蛾幼虫对药剂的敏感性存在显著差异,2—4龄幼虫随龄期的增加,药剂敏感性逐渐下降。     

郑州地区丝带凤蝶形态、生物学特性和生活史研究

通过野外观察、室内饲养等方法对郑州地区丝带凤蝶的生活史及生物学习性进行研究,记录了丝带凤蝶卵、幼虫、蛹、成虫等各虫态、各虫龄的发育历期和生物学习性.结果表明:丝带凤蝶在郑州地区一年发生4代,以蛹在石缝、落叶或土中越冬.卵、幼虫、蛹、成虫发育历期分别为:5~7d,19~24d,7~9d,12~15d,其中1~5龄幼虫发育历期分别为:3~5d、3~4d、4~7d、4~6d、5~7d.以蛹越冬,越冬蛹期190~220d.初孵幼虫无取食卵壳行为,低龄幼虫有群集取食习性.另外,对各虫态、各虫龄的外部形态也进行了详细描述.     

斜纹夜蛾前胸腺的生长发育研究

 通过解剖观察4龄至蛹期斜纹夜蛾前胸腺,对其形态特点和生长发育规律进行了研究,主要结果如下：发现斜纹夜蛾前胸腺由53个左右的圆形或椭圆型细胞成串组成,Y型,成对,外围包裹一层透明鞘膜,位于胸部第一气门的气管丛内;在斜纹夜蛾4龄到蛹期的发育过程中,前胸腺不发生有丝分裂,细胞数量基本恒定;前胸腺细胞直径在幼虫发育期间不断增大,斜纹夜蛾幼虫在4龄第1天的前胸腺直径为(28.80±0.47) μm,而到了6龄末期,则增加到(92.22±2.43) μm;幼虫期的斜纹夜蛾前胸腺细胞直径和虫体体质量呈显著相关,r=0.826,P=0.000,拟合曲线方程为Y=82.1X ^0.263;此外,幼虫期的斜纹夜蛾前胸腺细胞直径和虫体体长也呈现出显著相关,r=0.886,P=0.000,拟合曲线方程： Y=e^{(4.781-1.863/Z)}。     

稻纵卷叶螟人工饲料的研究

 以稻纵卷叶螟为研究对象,按不同配方配制了6种人工饲料分别用来饲养稻纵卷叶螟,以筛选出适合饲养稻纵卷叶螟的人工饲料。结果表明,在温度为24~26 ℃,相对湿度大于80%,光照条件大于14 h的条件下,其中饲料D、E、F饲养稻纵卷叶螟二龄幼虫只能完成二龄发育,少数幼虫存活到三龄或三龄以上;饲料C饲养稻纵卷叶螟二龄幼虫也只能完成三龄发育;而饲料A和B饲养的稻纵卷叶螟二龄幼虫能完成整个世代发育,存活率分别为26.17%和36.40%,接近对照组新鲜水稻叶饲养的存活率36.67%,且蛹质量和新鲜水稻叶饲养的幼虫没有显著差异,但与对照相比,幼虫历期延长4~6 d、化蛹率下降8%~9%、羽化率下降11%~12%。     

Synthesis dynamic and developmental profile of prothoracicotropic hormone between diapause- and nondiapause-destined individuals in Helicoverpa arrnigera

Biosynthesis and secretion of prothoracicotropic hormone （PTTH） of diapause- and nondiapausedestined individuals in Helicoverpa armigera were studied using whole-mount immunocytochemistry and enzyme-linked immunosorbent assay （ELISA）. The immunocytochemistry revealed that PTTH is expressed in two pairs of lateral neurosecretory cells of the brain. The presence of immunoreactivity has not significant difference between the brains of the diapause- and nondiapause-destined 6th instar larvae. However, the obvious differences of expressional pattern from day 4 pupae were observed between the two types. PTTH titers in hemolymph from the 6th instar larvae to pharate adults were measured by the ELISA. Although there were similar titer changes between the two types of individuals at the larval stage, a significant difference from developmental expression was detected at the pupal stage, suggesting that the expression and secretion of PTTH does play a crucial role in regulation of pupal diapause of H. armigera.     

Synthesis dynamic and developmental profile of prothoracicotropic hormone between diapause-and nondiapause-destined individuals in Helicoverpa armigera

Biosynthesis and secretion of prothoracicotropic hormone (PTTH) of diapause-and nondiapause-destined individuals in Helicoverpa armigera were studied using whole-mount immunocytochemistry and enzyme-linked immunosorbent assay (ELISA). The immunocytochemistry revealed that PTTH is expressed in two pairs of lateral neurosecretory cells of the brain. The presence of immunoreactivity has not significant difference between the brains of the diapause-and nondiapause-destined 6th instar larvae. However,the obvious differences of expressional pattern from day 4 pupae were observed be-tween the two types. PTTH titers in hemolymph from the 6th instar larvae to pharate adults were measured by the ELISA. Although there were similar titer changes between the two types of individuals at the larval stage,a significant difference from developmental expression was detected at the pupal stage,suggesting that the expression and secretion of PTTH does play a crucial role in regulation of pupal diapause of H. armigera.     

恒温饲养黄粉虫的研究

本研究在２８℃恒温室中进行。成虫平均寿命为３４．６天，雌虫羽化３天就能产卵。卵孵化期平均为７．２天。幼虫平均龄期为１２．６龄，幼虫各龄天数差异显著，９龄以上幼虫各龄天数呈显著的递增趋势。蛹期平均为６．０天。在２０—１２０头成虫梯度实验中，单位成虫产出的幼虫平均数与成虫数之间存在显著的负相关性。幼虫在饲料分布均匀的饲养盆中有向中间分布的趋势。羽化后成虫的水分含量和脂肪含量随天数增加而下降。蛹脂肪含量随天数增加而下降，水分含量则上升。低龄幼虫水分含量（６５．５７％）高于高龄幼虫（６１．８９％），高龄幼虫能值（６２５０．２ｃａｆ／ｇＤＭ）高于低龄幼虫（６０２５．３ｃａｆ／ｇＤＭ）．     

中华卵索线虫Ovomermis sinensis对蔬菜害虫的人工感染和菜田释放试验

1996—1997年,在福州,用中华卵索线虫Ovomermis sinensis(Chen et al)侵染期幼虫对当地主要蔬菜害虫,菜青虫、斜纹夜蛾和甜菜夜蛾等幼虫,在室内做人工感染试验。在室温20—28℃,寄生线虫与宿主昆虫的比例为为80:1的情况下,线虫对菜青虫、斜纹夜蛾和甜菜夜蛾幼虫的寄生率分别为50％,94％,92％。在当地土壤中无中华卵索线虫的空心菜田,设三个小区,每小区15m~2,各移植斜纹夜蛾2—3龄幼虫150头于菜株上,A区用12540条线虫侵染期幼虫混在2460克湿沙中,撤施于植株根部土面;B区用同样数量的线虫混在8公斤水中,喷洒在菜株上;C区为不释放线虫的对照区。于释放线虫后的第4天和第7天,从各小区随机回收斜纹夜蛾幼虫20头和30头,在室内单头饲养,检查线虫的寄生率和寄生强度。结果:第4天调查寄生效果相近,寄生率分别为61.1％,60％。第7天调查寄生率分别为76.7％,70％。而对照区的虫体中均未见有线虫寄生,寄生率为0。差别显著。在元白菜上释放中华卵索线虫侵染期幼虫,莱青虫的寄生率为6.6％。     

斜纹夜蛾人工与天然饲料主要质量指标的比较研究

本文报道用人工饲料饲养斜纹夜蛾，以主要质量指标与天然饲料比较，结果表明：人工饲料组抗病力强，蛹的重量大，成虫寿命长，存活率高，从而较好解决了大量繁殖斜纹夜蛾的饲养问题。     

松毛虫脊茧蜂生物学特性的研究

<正>松毛虫脊茧蜂是马尾松毛虫幼虫常见的寄生性天敌,国内分布广泛。在苏皖地区对松毛虫幼虫的平均寄生率为1.8～20.1％。该蜂在苏皖地区一年发生2代,以幼虫在越冬代3～4龄松毛虫幼虫体内越冬。翌年2～3月寄主幼虫虫体缩小,两端微尖,中间隆起呈纺锤形,固定在树皮下或小枝、针叶等部位。越冬代及第1代成虫发生期长,幼虫有滞育现象,因此生活史不整齐,有世代重叠现象。蛹期19～24天。成虫在白天羽化、交尾、产卵,平均寿命7.7～24.7天,补充营养可延长寿命。成虫有较强趋光性,脊茧蜂的诱虫量与松毛虫发生数量密切相关。茧蛹期有5种重寄生天敌,全年平均重寄生率18.6％,其中以窄柄姬蜂最为重要。     

宽带细腹食蚜蝇Sphaerophoria macrogaster生物学特性的初步研究

本文研究了宽带细腹食蚜蝇Sphaerophoria macrogaster(Thompson)的生物学特性,发现该食蚜蝇在福州一年发生7代,各代的历期分别为46.3天、30.9天、66.7天、23.1天、26.1天、37.1天与131.2天。主要以蛹在土壤中越冬和越夏,所以第7代与第3代的历期都很长,蛹期也比其他各代长,分别为100天与45天。每雌的平均产卵量为20.8粒。幼虫期的总捕蚜量为286.7头,其中2、3龄幼虫的捕蚜量占幼虫期总捕蚜量的98.2％。     

刚竹毒蛾生物学特性及防治研究

刚竹毒蛾Pantana phyllostachysae Chao 1年发生3代,以卵和初孵幼虫越冬,越冬幼虫翌年3月开始活动,6月上旬为第1代幼虫孵化盛期,8月下旬为第2代幼虫孵化盛期,11月出现第3代幼虫。气温是影响刚竹毒蛾危害的重要因素,在防治上要抓住幼虫3龄期前和成虫期进行防治,使用2.5%溴氰菊酯、80%敌敌畏和柴油按1:0.5:50制成的油烟剂防治效果最好。     

斜纹夜蛾杆状病毒流行病模拟模型研究

根据斜纹夜蛾生物生态学及其杆状病毒病流行的一般规律，建立了斜纹夜蛾杆状病毒流行病的微分方程模拟模型，模拟系统由１８个微分方程组成，可以模拟易感的和染病的１～６龄幼虫、蛹、成虫，卵的种群动态．模拟模型包含４个分室，即易感种群过程，染病种群过程，病毒在作物上的积累过程，易感种群和染病种群的相互转化过程．系统中纳入了作物生长对病毒数量的稀释效应，以及病毒数量的自然衰减作用．模型参数须由试验测定得到．给出了杆状病毒病的有关试验参数     

Ecdysteroids in the larvae of Opogona sacchari （Bojer）, a invasive alien pest

In order to understand the composition and quantitative variation of ecdysteriods in the larvae of Opogona sacchari (Bojer), a invasive alien pest, we analyzed the larval ecdysteroid composition and titers in this pest. The main component of ecdysteriods in the larvae of O. sacchari is 20-hydroxyecdysone, and also there is a little 26-hydroxyecdysone. The titer of ecdysteriods in the larvae from the 1st instar to the 7th instar was gotten higher gradually compared on ng ecdyster-oid/larva, but no regularity could be found about the titer if compared on ng ecdysteroid/g avoirdupois. There was only one peak of ecdysteroids (0.5475 ng/larva) showed at day 2 during the developmental time of the 6th instar larvae. However, there were two peaks appearing during the developmental time of the 7th instar larvae , one peak (0.29415 ng/larva) at day 3, another (0.214 ng/larva) at day 5.     

马尾松毛虫生物学特性及生物防治初探

马尾松毛虫在福建一年发生 2 - 3代 ,其 1龄和 2龄幼虫群集取食 ,成虫昼伏夜出 ,以 2 l:0 0 - 2 3:0 0时活动最盛 ,趋光性强 ,雌蛾产卵量平均为 193粒。通过生物农药“天时”对松毛虫四龄幼虫的毒力测定 ,结果表明 :“天时”对其幼虫具有较高的活性 ,4 8h的 LC50 为 0 .0 0 0 15 4mg/ m L。这为马尾松毛虫的综合防治提供了理论依据。     

珍贵绢丝昆虫天蚕的半纯饲料

本文报告了以白栎叶粉为叶因子的天蚕半纯饲料的数种配方。配方Ⅰ、Ⅱ适用于饲育1～3龄稚蚕,4龄开始改用鲜叶育,其幼虫总的存活率为61.54％～65.63％,幼虫历期为39.48～40.40天,茧层量为0.3558～0.3982g。配方Ⅸ适用于全期育,幼虫总的存活率为52.83％,历期53.53天,茧层量0.1826g。此外,并讨论了配方的改进途径。