The Susceptibilities of Oxya chinensis （Orthoptera： Acridoidea） to Malathion and Comparison of the Esterase Properties from Three Collected Populations in Tianjin Area,China

The susceptibilities of Oxya chinensis to malathion were studied in three populations collected from outskirt of Tianjin, China, using bioassays and biochemical analysis. Populations were chosen to represent different exposure to insecticides： BDG （Beidagang; low exposure）, BD （Baodi; high exposure previously but low exposure now）, and JN （Jinnan; high exposure）. The results showed that the LD50 values of BD and JN populations were 3.95- and 12.02-fold and 3.64- and 10.07- fold higher than that of BDG population in females and males, respectively. The LD50 values in females were higher than those in males. The results of biochemical analysis indicated that the esterase （EST） activities in JN population were higher than those in BD and BDG populations. They showed that when α-NA, α-NB, and α-NA were used as substrates, females＇ EST activities of JN population were 1.11-, 1.30-, and 1.14-fold and 1.39-, 1.59-, and 1.54-fold higher than those of BD and BDG populations, respectively. When α-NA, α-NB, and β-NA were used as substrates, males＇ EST activities of JN population were 1.13-, 1.12-, and 1,00-fold and 1.20-, 1.14-, and 1.07-fold higher than those of BD and BDG populations, respectively. The results also showed that the specific activities of the females were higher than those of the males in the BD and JN populations, whereas the specific activities of the males were higher than those of the females in the BDG population. The results of bioassay were consistent with those of biochemical analysis. Thus, it was inferred that the elevated ESTs activities might play an important role in conferring the differences of susceptibility of O. chinensis to malathion in the three collected populations. Enzyme kinetic studies indicated that the Km and Vmax values were different among the three collected populations and between the females and the males. The observed changes in the kinetic parameters might be explained by differential expression patterns of isozymes so that the insect esterases have different affinities and maximum velocities toward the same substrate.     

重金属镉和铬在中华稻蝗（Oxya chinensis）体内的组织分布

为研究重金属在中华稻蝗(Oxya chinensis)自然种群体内的累积分布,以山西省代县水稻田中华稻蝗为研究对象,用火焰原子吸收法测定中华稻蝗不同组织部位的镉和铬含量.研究结果表明:镉和铬在中华稻蝗自然种群不同组织部位的富集量不同,且雌雄间存在一定的差异.镉在雌虫体内的富集顺序为中肠＞后肠＞前肠＞翅＞头＞卵巢＞足＞体壁;在雄虫体内为中肠＞前肠＞后肠＞足＞头＞体壁.镉在雌雄中华稻蝗消化道内均有较高的富集并以中肠的累积量最高,雌虫为6.7984 mg·kg-1,雄虫为3.347 7 mg·kg-1,且与其他组织部位间存在显著差异(P＜0.001).中华稻蝗雌虫各组织部位对铬的累积浓度依次为中肠＞足＞体壁＞头＞卵巢＞前肠＞翅＞后肠,中华稻蝗雄虫体内铬浓度的分布依次为足＞体壁＞中肠＞头＞前肠＞精巢＞后肠.多因素方差分析结果表明,自然条件下雌雄中华稻蝗对重金属镉和铬的累积具有组织特异性,两种重金属在中华稻蝗体内的累积规律有所不同.     

镉锌处理麦苗对中华稻蝗（Oxya chinensis）体内锌、镉水平及生化指标的影响

为了研究Cd、Zn污染对中华稻蝗生理生化的影响,选用不同浓度Ｃｄ、Ｚｎ溶液（Ｃｄ ０＋Ｚｎ ０,Ｃｄ ２０＋Ｚｎ ０,Ｃｄ ２０＋Ｚｎ ５０,Ｃｄ ２０＋Ｚｎ １００,Ｃｄ ２０＋Ｚｎ ２００）ｍｇ·Ｌ－１培养麦苗饲喂中华稻蝗（Ｏｘｙａ ｃｈｉｎｅｎｓｉｓ）进行慢性染毒,测定麦苗和虫体（４龄若虫）中Ｃｄ与Ｚｎ蓄积量、虫体中丙二醛（ＭＤＡ）含量、超氧化物歧化酶（ＳＯＤ）及谷胱甘肽过氧化物酶（ＧＰｘ）活性和总抗氧化能力（Ｔ－Ａｏｃ）。研究结果显示,在Ｃｄ浓度恒定的情况下,随Ｚｎ处理浓度的增大,麦苗和虫体中Ｚｎ含量显著上升,（Ｃｄ ２０＋Ｚｎ ２００）ｍｇ·Ｌ－１处理组麦苗和虫体Ｚｎ含量分别为对照组的２．０３和１．６３倍;Ｃｄ含量呈先升高后降低趋势,在（Ｃｄ ２０＋Ｚｎ １００）ｍｇ·Ｌ－１处理组达到最高值,分别为１０．４０、４．３５ μｇ·ｇ－１,（Ｃｄ ２０＋Ｚｎ ２００）ｍｇ·Ｌ－１处理组下降到７．３６、３．３５ μｇ·ｇ－１。在Ｃｄ和Ｚｎ联合作用下,随着Ｚｎ浓度的增加,中华稻蝗体内的ＭＤＡ含量升高。ＳＯＤ表现出先升高、后降低的趋势。与对照组相比,Ｃｄ单一处理组ＧＰｘ活性增加,随着Ｚｎ的加入,其ＧＰｘ活性降低。Ｔ－Ａｏｃ在（Ｃｄ ２０＋Ｚｎ １００）ｍｇ·Ｌ－１处理组活性最高。研究结果表明,低浓度Ｚｎ的加入可以增加中华稻蝗对Ｃｄ的富集,Ｃd和Zn的联合作用能够引起中华稻蝗脂质过氧化损伤。     

5-氨基乙酰丙酸对中华稻蝗（Oxya chinensis）的杀虫活性及对3种酶活性的影响

 【目的】研究5-氨基乙酰丙酸（5-aminolevulinic acid,ALA）对中华稻蝗（Oxya chinensis）的杀虫活性及对3种酶活性的影响。【方法】以中华稻蝗4龄若虫为试验材料,用不同剂量的ALA（A1：250 mmol•L-1;A2：450 mmol•L-1;A3：750 mmol•L-1;A4：1 000 mmol•L-1）处理中华稻蝗,观察其对中华稻蝗的毒性效应和对其体内乙酰胆碱酯酶（AChE）、谷胱甘肽S-转移酶（GSTs）和谷胱甘肽过氧化物酶（GPx）活性的影响。【结果】不同剂量ALA处理组中华稻蝗死亡率依处理剂量呈现上升趋势,高浓度处理组A3、A4的死亡率分别达到66.19%和80.21%;LD50值为3.61（3.29～3.93）mg•g-1虫重（95%置信范围）。生化研究结果显示,最高浓度A4处理组雌、雄虫体内AChE活性分别较对照组下降了51.53%和42.65%,差异显著（P＜0.05）;GPx活性分别较对照组下降了42.82%和43.85%,差异显著（P＜0.05）。同时,中华稻蝗GSTs活性随ALA处理剂量升高而增高,A4处理组雌、雄虫体内GSTs活性分别较对照组升高了171.05%及97.42%,差异显著（P＜0.05）。【结论】ALA对雌、雄中华稻蝗均有明显的毒性效应;ALA可引起AChE和GPx光失活,从而导致中华稻蝗神经传导受阻同时抵御氧化损伤的能力下降;高剂量ALA激活GSTs,可引发昆虫对光毒性物质的自身反馈抵御反应。     

铬在中华稻蝗（Oxya chinensis）体内的累积及对抗氧化系统的影响

昆虫体内的重金属主要是通过消化途径实现代谢过程的.本文中以不同浓度六价铬(Cr6+)溶液(0、7.5、15、30 mg·L-1)培育的小麦对中华稻蝗(Oxya chinensis)从4龄若虫开始进行慢性染毒,待其发育到成虫时分别测定虫体、粪便、小麦叶片内的Cr含量以及成虫体内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPx)和总抗氧化能力(T-Aoc).结果显示,生长于0、7.5、15、30 mg·L-1 Cr6+溶液中的小麦,其叶片中Cr浓度分别为5.77、6.85、9.88、18.33 μg·g-1.随着Cr6+浓度的增加,虫体内和粪便中Cr的累积量也逐渐增大,在30 mg·L-1时达到最大值.中华稻蝗体内SOD活力随着处理浓度的增加,变化不明显,未达到显著水平.而CAT、GPx活力和T-Aoc随着处理浓度的增加,呈先升高后降低的趋势,在7.5mg·L-1时达到最大值.本文结果表明,中华稻蝗体内的Cr含量随着染毒浓度的增加而增大,是对环境中重金属Cr污染的一种间接反应.通过测定中华稻蝗体内的Cr含量,可以对环境中Cr污染进行评估;同时,中华稻蝗抗氧化酶系统在机体防御过氧化物损伤方面起着重要作用.     

Comparative Morphology and Morphometry of Six Biotypes of Bemisia tabaci （Hemiptera： Aleyrodidae） from China

Morphology and morphometry of six biotypes(B,Q,Cv,ZHJ-1,ZHJ-2 and ZHJ-3) of Bemisia tabaci(Gennadius) from China on cotton plants were studied by using microscopes.Nymphal body sizes and characters were measured and observed,especially on the 4th instar(pupal case),including the vasiform orifice,operculum,lingula,length and thickness of anterior and posterior wax margins,width of thoracic tracheal combs.Adult characters of both sexes were investigated including the body size,compound eyes,antennal segments,vasiform orifice,hind tarsi and genitals.The results indicated that differences of some morphological characters or morphometrics were significant among the six biotypes of B.tabaci in China:(1) Pupal sizes of the exotic biotypes(B and Q) were significantly larger than the indigenous biotypes with the following order as B>Q>ZHJ-1>Cv>ZHJ-3>ZHJ-2;(2) for both male and female adults,sizes of all characters investigated in the invading biotypes(B and Q),especially B,were much larger than those of the indigenous ones.     

Gene Cloning and Tissue-Specific Microplitis mediator （Hymenoptera： Expression of G Protein β Subunit in Braconidae）

A gene encoding a novel G protein β subunit of β1 subclass, GβMmed was isolated from Microplitis mediator （Hymenoptera： Braconidae）. The full-length sequence of GβMmed is 1 119 bp, the cDNA contains a 1 023 bp open reading frame that encodes a protein with 340 amino acids, and the predicted molecular weight of GβMmed is 37.23 kDa and isoelectric point is 5.86. By the quantitative real-time RT-PCR method, the tissue-specific expression and quantitative changes in the developmental expression profile of GβMmed were detected. It was found that GβMmed was abundantly expressed in M. mediator antennae, head （without antennae）, thorax, abdomen, legs and the wings, and especially at high levels in abdomen. In antennae, expression varied through 1st day before emergence to 5-d-old adults, and had equal expression levels detected in females and males in total. In head, GβMmed expresses while initially high in females, and have another peaked in stage 4 and 1st day, in males showed a peak of GβMmed expression prior to emergence and relatively low levels after emergence. In female abdomen GβMmed expression levels have two peaks in stage 1 and the 5th d, but just have one peak in male abdomen in stage 1. In all other tissues expression was low and stable.     

Comparative Studies of Substrate and Inhibitor Specificity of Glutathione S-Transferases in Six Tissues of Oxya chinensis (Thunberg) (Orthoptera: Acrididae)

Specific activity, substrate specificity, and kinetic parameters (Km and Vmax) of glutathione S-transferases (GSTs) towards three substrates, 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB), and p-nitrobenzene chloride (pNBC) were investigated in six tissues (foregut, midgut, hindgut, fat body, hemolymph, and muscle) of Oxya chinensis. In addition, the inhibition in vitro (ethacrynic acid, and Cibacron Blue 3GA) of Oxya chinensis in the six tissues was also investigated. Glutathione S-transferase activity was detected in all the six tissues examined. The rank order of GST activities towards CDNB was fat body > midgut > hindgut > muscle > foregut > hemolymph both in females and males. Glutathione 5-transferase activities in the fat body in females and males were 1.3- to 10.4-fold and 1.1- to 10.0-fold higher than those in the other tissues. The rank order of GST activities towards the other substrates changed slightly. From these results, it was inferred that GSTs in the fat body and midgut played important roles in detoxifying xenobiotics including insecticides and plant allelochemicals in O. chinensis. In the three substrates examined, CDNB seemed to be the best substrate, followed by pNBC and DCNB. The kinetic parameters of GSTs were different among the six tissues. This suggested that GSTs in different tissues have various affinities and catalytic efficiency to substrates. In vitro inhibition study showed that the median inhibition concentration (IC50) values of the two inhibitors to GSTs from the six tissues were different. The results suggested that the two inhibitors have different inhibition potency to GSTs from the different tissues. The observed changes in kinetic parameters and inhibition in vitro among the six tissues of the insect might suggest that the number and structure of isoenzymes and their rate of expression varied for the different tissues.     

Study on Insecticidal Activities and Effect on Three Kinds of Enzymes by 5-Aminolevulinic Acid on Oxya chinensis

Insecticidal activities and effects on three enzymic activities caused by 5-aminolevulinic acid （ALA） on Oxya chinensis were studied. Fourth-instar nymphs of O. chinensis were treated with different doses ofALA （A1,250 mM; A2, 450 mM; A3,750 mM; A4, 1 000 mM）. Mortality and the activities of acetylcholinesterase （ACHE）, glutathione S-transferase （GSTs）, and glutathione peroxidase （GPx） were determinated. The mortality of O. chinensis rose with an increasing dose of ALA. The mortality of high-dose treatments A3 and A4 reached 66.19 and 80.21%, respectively. The value of LD50 was 3.61 （3.29-3.93） mg·g^-1 body weight （95% confidence interval）. Biochemical studies showed that the activities of AChE and GPx in the A4 treatment declined by 51.53 and 42.82% in the female, and 42.65 and 43.85% in the male compared to the control, respectively, and the degree of decline reached a significant level at P 〈 0.05. Meanwhile, the GSTs activities of O. chinensis enhanced with increasing dose of ALA. The GSTs activities of female and male O. chinensis in the A4 treatment remarkably increased by 171.05 and 97.42% compared to the control （P〈 0.05）. ALA had an obviously toxic effect on O. chinensis. Moreover, ALA caused the photoinactivation of AChE and GPx, which induced nerve transmission blocking and the capability to defend oxidation damage declining. Meanwhile, a high dose of ALA could activate GSTs, which caused a feedback inhibition of the insect to the phototoxic substance.     

三种重金属对中华稻蝗金属硫蛋白基因表达的影响

以栖息于稻田且主要取食水稻茎叶的中华稻蝗(Oxya chinensis)成虫为供试材料,经氯化镉、氯化铜和硫酸锌(Cd Cl2、Cu Cl2和Zn SO4)3种重金属急性染毒,采用RT-q PCR技术检测中华稻蝗2个金属硫蛋白基因(Oxya chinensis metallothionein,Oc MT1,Oc MT2)在精巢、卵巢和肌肉中的表达变化。结果表明,3种重金属均可诱导中华稻蝗MT基因不同程度的上调表达。经Cd急性处理后,3个器官组织中Oc MT1和Oc MT2表达水平在一定浓度范围内随着Cd浓度的增高而诱导表达上调;经Cu急性处理后,精巢和卵巢中Oc MT1在最低浓度时的诱导表达量最高,Oc MT2表达水平随着Cu浓度的增大而升高,肌肉中2个MT基因随着Cu浓度的增大而升高;经Zn处理后,Oc MT1和Oc MT2表达水平随着Zn浓度的升高而升高。由实验结果可以看出,3种重金属对中华稻蝗MT在不同器官组织均有诱导表达作用,但各浓度处理后其诱导表达水平不同,Oc MT对不同重金属的敏感性具有显著差异。     

镉急性染毒对中华稻蝗精卵巢小分子热休克蛋白基因表达的影响

小分子热休克蛋白(s HSPs)能够被环境胁迫诱导,采用不同浓度氯化镉(Cd Cl2)溶液对中华稻蝗5龄若虫进行急性染毒,利用Real-time PCR技术对5个小分子热休克蛋白基因Oc HSP19.1、Oc HSP19.8、Oc HSP20.4、Oc HSP20.7和Oc HSP21.1在精巢和卵巢的表达进行了分析。结果表明:在精巢内,Oc HSP19.1和Oc HSP19.8基因经0.16μg·μL-1Cd2+处理,其在不同处理时间的表达水平与对照组相比均显著升高;经0.32μg·μL-1Cd2+处理,其在2 h表达水平最高,之后显著降低;经0.48μg·μL-1Cd2+处理,Oc HSP19.1基因在2 h和6 h的表达量均高于对照组,在12 h的表达量低于对照组,Oc HSP19.8基因在2 h的表达量高于对照组,在6 h的表达量低于对照组,之后二者表达量都显著升高,在36 h表达量最高,分别为对照组的6.3倍和5.4倍。在卵巢内,Oc HSP19.1和Oc HSP21.1基因经0.16μg·μL-1和0.48μg·μL-1Cd2+处理,其在不同处理时间的表达水平与对照组相比无显著差异;经0.32μg·μL-1Cd2+处理,Oc HSP19.1基因在6 h和12 h的表达水平高于对照组,但在24 h低于对照组,Oc HSP21.1基因在2、6、12 h和24 h的表达水平与对照组相比均显著降低,但二者都在36 h表达量最高,分别为对照组的4.8倍和4.6倍;经0.16μg·μL-1和0.48μg·μL-1Cd2+处理,Oc HSP20.7基因在2 h表达水平高于对照组,经0.32μg·μL-1Cd2+处理,该基因的表达水平随着时间的延长出现先升高后降低的趋势。Oc HSP21.1基因在精巢内和Oc HSP20.4基因在卵巢内的表达水平与对照组相比无显著差异。研究结果显示,Cd急性诱导中华稻蝗5个Ocs HSPs基因在精巢和卵巢的表达模式不同,其表达量与Cd浓度和作用时间相关。     

不同组织器官中华蛇根草绿原酸含量的比较研究

目的 比较中华蛇根草不同组织器官中绿原酸的含量。方法 选用Inertsil C₁₈色谱柱,以甲醇-0.02%磷酸溶液（20：80）为流动相,流速为1.0 mL/min,检测波长为325 nm,柱温40℃。结果 绿原酸在0.027~1.700 μg（r=0.999 9）范围内线性关系良好。2月花期采收的中华蛇根草茎、叶、花中绿原酸的含量分别为3.39、0.77、22.79 mg/g。结论 中华蛇根草不同组织器官绿原酸含量差异较大,其中花含量最高。该方法能准确、快速地进行定性定量检测,可用于中华蛇根草中绿原酸含量的测定。     

罗红霉素对中国圆田螺ERND酶活性的影响

过量使用的罗红霉素等抗生素会经不同途径流入水体,溶入沉积物,造成对水生生态系统的危害.本文将底栖动物中国圆田螺(Cipangopaludina chinensis)暴露于罗红霉素中,分别检测其胃、肝脏、肾脏、卵巢和肌肉组织中的红霉素-N-脱甲基酶(ERND)活性,来监测沉积物中抗生素对底栖生物的影响。结果表明,中国圆田螺主要组织微粒体中具有细胞色素P450亚型活性,但它们在中国圆田螺内的分布和活性不存在组织和器官差异性。连续给药2 d后中国圆田螺的肝脏、肾脏、胃和卵巢肌肉组织中的ERND的活性都会升高,呈现明显的剂量-效应关系,到第3天达到最高点,第4天却开始下降。其总体趋势是先促进后抑制,但不同浓度的罗红霉素引起的影响差异并不大。从对照组和各个实验组田螺的存活状况看来,罗红霉素作为一种抗生素,对中国圆田螺没有致死效应,但本实验所使用的250倍环境浓度、500倍环境浓度以及750倍环境浓度已经可以对田螺各组织中ERND活性产生明显的影响。     

Comparisons of Properties of Acetylcholinesterase from Two Field-Collected Populations of Oxya chinensis Thunberg (Orthoptera: Acrididae) and the Role of Acetylcholinesterase in the Susceptibility to Malathion

In this study, acetylcholinesterase (AChE) was extracted from two field-collected populations of Oxya chinensis (Xinxiang City, Henan Province and Changzhi City, Shanxi Province). AChE activities were decreased when concentrations of ATC increased, showing a characteristic phenomenon of substrate inhibition at high concentration in both populations. Such inhibition occurred at relatively low concentration for AChE from Xinxiang population but relatively high for AChE from Changzhi population. The kinetic study showed that there were no significant differences between the two populations in the Km values. The Km value in Changzhi population was only 1.09-fold higher than that in Xinxiang population. However,significant differences were observed between the two populations in Vmax values. The Vmaxvalue in Changzhi population was 1.32-fold higher than that in Xinxiang population. The inhibition study in vitro showed that the AChE from both populations exhibited similar rank order in sensitivity to inhibition by three OPs, as determined by comparison of their bimolecular rate constants (ki), from the most potent inhibition to the least was chlopyrifos-oxon ＞ paraoxon ＞demeton-s-methyl for AChE from the two populations and that the ki values in Xinxiang population were lower than those in Changzhi population. The I50 values of AChE from Xinxiang population were 4.84-, 2.66-, and 1.92-fold less sensitive to inhibition by paraoxon, chlopyrifos-oxon, and demeton-s-methyl. These results were consistent with the results in bioassay. It is inferred that AChE insensitivity to OP insecticides plays an important role in the differences of insusceptibility of Oxya chinensis to malathion between the two populations.     

羊草与克氏针茅氮元素含量对亚洲小车蝗取食选择的影响

选择2种内蒙古草原的优势草种羊草和克式针茅,通过人工饲喂蝗虫取食的方法,分别测定亚洲小车蝗的5龄蝻期以及成虫在未施肥(ON)和施肥(HN)条件下对于2种不同草种的取食量和选择频次,并研究N元素变化对于亚洲小车蝗取食选择性的影响。结果表明,在蝻期,N元素不是其取食选择性和食量的决定因素。而在成虫期,亚洲小车蝗特别是雄性更喜欢低N植物作为其食物。亚洲小车蝗对羊草或针茅的选择取食随发育阶段、性别和草的N含量进行调整,但在进化过程中趋向于选择低氮的植物。     

~(14)C示踪同化物在柽柳和管花肉苁蓉寄生系统内的分配

利用14 C同位素示踪技术,探讨碳同化物在柽柳和管花肉苁蓉寄生系统内的分配,为明确两者同化物的源库关系及光合产物调控提供理论依据。结果表明,不同时期柽柳和管花肉苁蓉中14 C同化物的分配比例差异显著,8-10月分配给柽柳的14 C同化物比例显著降低,分配给管花肉苁蓉的比例显著升高,10月达到峰值,柽柳和管花肉苁蓉中14 C同化物的比例分别为14.95%~20.54%和79.46%~85.05%。随着管花肉苁蓉寄生数量的增加,分配给柽柳的14 C同化物比例显著降低,分配给管花肉苁蓉的比例显著升高,管花肉苁蓉的14 C同化物分配比例表现为接种8个的处理接种4个的处理接种1个的处理。14 C同化物在柽柳和管花肉苁蓉寄生系统内的分配比例随肉苁蓉寄生数量和生长时间而变化。     

野生与种植黄连植株不同部位的生物碱含量比较研究

目的 采用UV和HPLC法比较野生与种植黄连植株不同部位生物碱含量差异。方法 UV法在波长345 nm处测定黄连总生物碱含量,HPLC采用C₁₈（4.6 mm×250 mm,5 μm）色谱柱,乙腈和0.4%磷酸水溶液（25：75）等度洗脱,流速1.0 mL/min,进样量10 μL,检测波长345 nm,柱温30℃以测定盐酸小檗碱含量。结果 黄连不同部位的总生物碱含量：种植黄连根茎含（9.88±0.03）%、须根含（6.41±0.03）%、茎叶含（1.92±0.04）%;野生黄连根茎含（7.95±0.03）%、茎叶含（0.64±0.03）%。黄连不同部位的的盐酸小檗碱含量：种植黄连根茎含（0.45±0.04）%、须根含（0.17±0.03）%、茎叶含（0.09±0.03）%;野生黄连根茎含（0.38±0.03）%、茎叶含（0.16±0.03）%。结论 种植黄连植株不同部位的总生物碱含量高于野生黄连,但其盐酸小檗碱含量低于野生黄连植株;野生与种植黄连均为根茎部总生物碱和盐酸小檗碱含量最高。