嗜卷书虱低氧耐性品系的选育及其遗传稳定性和生态适合度研究

室内恒温条件下以人工饲料饲养的嗜卷书虱Ｌｉｐｏｓｃｅｌｉｓ ｂｏｓｔｒｙｃｈｏｐｈｉｌａ Ｂａｄｏｎｎｅｌ成虫,分别在０．５％和１％Ｏ２组配的气调环境中以７％左右的选择压力处理,以选育其耐低氧气调性。选育至３０低氧品系ＬＯＣ１和ＬＯＣ２,以ＬＴ５０为标准其性倍数分别达４．７和３．９倍。整个选育过程中,气调暴露时间对数值与死亡率机率值间的回归直线基本平行,其值均低于敏感基线的斜率值,这表明嗜卷书虱对     

嗜卷书虱气调抗性形成过程中能源物质的积累与利用

报道了嗜卷书虱对高二氧化碳,低氧气调抗性形成过程中能源物质的积累以及抗性形成后在气调胁迫下能源物质的利用情况。结果表明随着抗性水平的提高。嗜卷书虱体内甘油三酯,多糖以及游离氨基酸含量均显升高。在气调胁迫环境下,嗜卷书虱抗性品系能源物质的消耗率明显低于敏感品系,甘油三酯的积累以及在气调摁迫下缓慢消耗可能是其抗气调性的主要内在机理之一。     

嗜卷书虱实验种群生命表的研究

在不同温度和湿度条件下对嗜卷书虱进行饲养,分别组建春实验种群特定年龄和特定时间生命表,并应用Morris模式及SWeibull频数分布以探讨温、湿度与嗜卷书虱种群数量变动的关系。结果表明,温、湿度对存活率的作用是影响该实验种群趋势指数（I）值最重要的因子,在适宜温、湿度条件下,种群存活曲线属DeeveyⅠ型,而在不太适宜条件下则属DeeveyⅢ型,理论上30.63℃时周限增长率（λ）最大,达1.0628倍／天,该虫发育和繁殖的最适温区为28-30℃,最适相对湿度在80％左右。     

嗜卷书虱的实验生态研究

在8种温度(17.5～35℃)及5种相对湿度(50%、60%、70%、80%和90%)条件下,以全麦粉、酵母粉、脱脂奶粉(10∶1∶1)为食料,系统研究了嗜卷书虱Liposcelis bostrychophila Badonnel实验种群生态学特性。获得了该虫在不同温、湿度条件下生长发育、生存和繁殖的一系列特性和参数,包括各虫态发育历期、存活率、发育起点温度、有效积温和平均繁殖力等,并建立了发育速率、存活率及繁殖力的理论模型。     

不同食物对嗜卷书虱发育和繁殖的影响

通过单头饲养方法综合比较了嗜卷书虱取食９种基本食物或食物组合的发育和繁殖情况,结果表明全麦粉最有利于该虫的发育和繁殖;在全麦粉中加入少量酵母粉和脱脂奶粉后,该虫发育明显加快、存活率及繁殖力均显著提高。此外还就该虫嗜食不同食物的原因进行了探讨。     

硅藻土及其混配剂对书虱的防治效果

采用拌粮法 ,用硅藻土单剂、配方 1 (硅藻土 +95 %马拉硫磷EC)、配方 2 (硅藻土 +2 . 5 %溴氰菊酯EC)、配方 3 (硅藻土 +80 %敌敌畏EC)、配方 4(硅藻土 +0 . 4%天惠虫清EC)、配方 5 (硅藻土 +5 %双氧威WP)、配方 6(硅藻土 +5 %抑太保EC)对嗜卷书虱Liposcelisbostrychophila进行防治研究 ,结果表明 :配方 4为优选配方 ,处理 2 4h后 ,3种浓度的致死率均达到 1 0 0 % ;配方 1、配方 2、配方 3、配方 5、配方 6对嗜卷书虱的致死率处理 48h后达到 1 0 0 % ;单用硅藻土处理 96h后达到 1 0 0 % ,各配方处理间差异极显著。     

两种书虱微卫星富集文库的构建及比较

利用链霉亲和素与生物素之间的强亲和性原理,将链霉亲和素偶联的磁珠与微卫星探针(AC)12、(TC)12、(ATC)8、(ATG)8、(AAC)8、(ATAC)6及(GATA)6退火结合后,再亲和捕捉含接头和微卫星序列的单链书虱基因组DNA限制性酶切目的片段,经PCR扩增形成双链后进行克隆、建库。结果表明本研究成功构建了嗜卷书虱和嗜虫书虱共13个微卫星富集文库,包括6个嗜卷书虱文库,7个嗜虫书虱文库,其平均阳性克隆率为71.17%。经检测发现共得到两种书虱260个微卫星位点。这两种书虱微卫星富集文库的建立和高多态性微卫星位点的筛选将为嗜卷书虱和嗜虫书虱的种群遗传与进化、基因连锁图谱构建、分子系统发育研究等提供大量分子遗传标记,对其在实仓中的持续控制提供遗传学信息。     

褐飞虱抗吡虫啉品系生物适合度研究

毒力测定结果显示 ,虽然褐飞虱NilaparvatalugensSt l田间品系对吡虫啉还没有表现出明显的抗性 ,但室内筛选品系已经出现了一定水平的抗性 ,抗性品系 1 (R1)和抗性品系 2 (R2 )的抗性倍数分别为 2 5 3 8和 68 92。通过建立抗性品系、田间种群和敏感品系的生命表 ,发现抗性品系适合度显著下降 ,而且R2 品系下降的幅度明显大于R1品系。存在显著变化的因素有低龄若虫存活率、成虫羽化率、交配率、产卵量和孵化率下降 ,雌虫寿命缩短 ;R2 品系还表现为卵历期延长 ,3龄若虫至 5龄若虫存活率下降。R2 品系产卵高峰期迟 ,高峰期日虫量显著低于敏感品系和田间种群。用种群数量趋势指数 (I)来确定抗性品系的相对生物适合度 ,发现与敏感性品系相比 ,R1品系和R2 品系的相对适合度分别为0 60 9和 0 2 45。     

嗜卷书虱高CO_2抗性品系的选育及其适合度研究(英文)

室内恒温条件下以人工饲料饲养的嗜卷书虱 Ｌｉｐｏｓｃｅｌｉｓ ｂｏｓｔｒｙｃｈｏｐｈｉｌａ Ｂａｄｏｎｎｅｌ成虫,分别在３５％和５５％ＣＯ_２。（２１％Ｏ_２,Ｎ_２作为平衡气体使用）组配的气调环境中以７０％的选择压力处理,以选育其抗高ＣＯ_２气调性。选育至３０代获得抗性品系ＨＣＣ_１和ＨＣＣ_２,以ＬＴ_５０为标准,其抗性倍数分别达４．６和５．３倍。整个选育过程中,气调暴露时间对数值与死亡率机率值间的回归直线基本平行,且斜率值均低于敏感基线的斜率值,这表明嗜卷书虱对高ＣＯ_２抗性发展的基因潜能至第３０代仍未耗尽。两个抗性品系的抗性均不太稳定,去除选择压力后抗性显著下降,且两抗性品系均具有繁殖不利性即适合度缺陷。以净增值率为指标衡量,ＨＣＣ_１和ＨＣＣ_２相对于敏感品系分别具有０．５２和０．４５的适合度。     

嗜卷书虱Cu/Zn-SOD1,Cu/Zn-SOD2和Fe/Mn-SOD的克隆及对高低温胁迫的响应

【目的】揭示嗜卷书虱Liposcelis bostrychophila超氧化物歧化酶基因在响应高低温胁迫中的作用。【方法】通过RT-PCR克隆嗜卷书虱3个超氧化物歧化酶基因Cu/Zn-SOD1,Cu/Zn-SOD2和Fe/Mn-SOD cDNA,利用生物信息学方法分析其序列特征;采用RT-qPCR技术检测Cu/Zn-SOD1,Cu/Zn-SOD2和Fe/Mn-SOD在高温(42℃)和低温(4℃)胁迫下0, 1和2 h时成虫中的相对表达量。【结果】克隆获得嗜卷书虱LbCu/Zn-SOD1,LbCu/Zn-SOD2和LbFe/Mn-SOD(GenBank登录号分别为OQ938782, OQ938783和OQ938784),开放阅读框(ORF)分别长465, 630和636 bp,分别编码154, 209和211个氨基酸,编码蛋白质相对分子量分别为15.85, 22.33和23.72 kD,等电点分别为6.17, 7.68和6.79;LbCu/Zn-SOD1和LbCu/Zn-SOD2分别具有1个和2个Cu/Zn超氧化物歧化酶特征,LbFe/Mn-SOD具有1个Fe/Mn超氧化物歧化酶特征。系...     

Toxicological and biochemical characterizations of GSTs in Liposcelis bostrychophila Badonnel (Psocop., Liposcelididae)

Abstract: The toxicological and biochemical characteristics of glutathione S‐transferases (GSTs) in the resistant and susceptible strains of Liposcelis bostrychophila were investigated. The two resistant strains were the dichlorvos‐resistant strain (DDVP‐R) and PH₃‐resistant strain (PH₃‐R), and the resistance factors were 22.36 and 4.51, respectively. Compared with their susceptible counterparts, the activities per insect and specific activities of GSTs in DDVP‐R and PH₃‐R were significantly higher. The apparent Michaelis–Menten constant values (K_m) for 1‐chloro‐2,4‐dinitrobenzene (CDNB) were obviously lower in DDVP‐R and PH₃‐R (i.e. lower K_m values, 1.5625 mm for DDVP‐R and 0.6230 mm for PH₃‐R) when compared with their susceptible counterpart (K_m = 3.5520), indicating a higher affinity to the substrate CDNB in resistant strains. In contrast, the catalytic activity of GSTs towards CDNB in the susceptible strain was significantly higher than those in resistant strains. It was noticeable that when reduced glutathione (GSH) was used as substrate, GSTs from resistant strains both indicated a significantly declined affinity. For the catalytic activity of GSTs towards GSH, only the V_max value in DDVP‐R increased significantly compared with that from the susceptible strain, suggesting an overexpression of GST in this resistant strain. The inhibition kinetics of insecticides to GSTs in vitro revealed that dichlorvos and paraoxon possessed excellent inhibition effects on GSTs. The susceptible strain showed higher sensitivity (I₅₀ = 0.9004 mm ) to dichlorvos than DDVP‐R and PH₃‐R (higher I₅₀s, 8.0955 mm for DDVP‐R and 9.3346 mm for PH₃‐R). As for paraoxon, there was a similar situation. The resistant strains both suggested a higher I₅₀ (1.8735 mm for DDVP‐R, and 0.4291 mm for PH₃‐R) compared with the susceptible strain (0.2943 mm ). These suggested that an elevated detoxification ability of GSTs developed in the resistant strains.     

储藏物害虫嗜卷书虱对DDVP熏蒸的行为反应与致死剂量

1 引言 嗜卷书虱(Liposcelis bostrychophila)属啮虫目虱啮科。其体形微小,食性复杂,栖息场地多在粮食仓库及食品加工厂、图书馆、标本馆等地。大量发生时可造成严重损失,传播微生物,并以其尸体、排泄物等污染储藏的粮食和其它储藏物品。王进军等调查发现,在我国“双低”和“三低”贮粮的粮仓中,书虱已成为优势种群,对贮粮安全构成了威胁。使用病原真菌和细菌来防治嗜卷书虱,很难达到理想效果,即使采用菊酯类杀虫剂也难以奏效,贮粮熏蒸中普遍使用的溴甲烷(CH_3Br)和磷化氢(PH_3)对嗜卷书虱的防治效果也不很理想。利用昆虫生长调节剂防治嗜卷书虱的研究已有一些报道,但在具体应用上还存在着一些问题。气调措施可应用于控制书虱种群的增长,但书虱的抗气性发展很快,     

SELECTION OF RESISTANCE STRAINS IN LIPOSCELIS BOSTRYCHOPHILA BADONNEL TO CO2-ENRICHED ATMOSPHERES*

Abstract Adults of the psocid Liposcelis bostrychophila Badonnel were exposed to atmospheres containing 35% and 55% CO₂ for 30 generations to select strains resistant to high CO₂ content (HCC). Selection pressure was maintained at around 70% of mortality. At the 30th generation, comparison of sensitivities between the selected strains (HCC₁ and HCC₂) and the original susceptible strain (MA-S) revealed a resistance factor (RF) at the 50% mortality level (LT₅₀) of 4. 6-and 5. 3-folds, respectively. Throughout the selection process, log-time against probit-mortality lines remained roughly parallel and the slopes remained lower than that of MA-S strain until the last generation. It is inplied that the genetic potential of L. bostrychophila to develop resistance to CO₂ was not exhausted until the 30th generation. Removal of selection pressure for 5 generations from 2 sub-populations of two selected strains from the 25th generation caused significant reduction in resistance. In the absence of MAs exposure, the two selected strains (HCC₁ and HCC₂) possessed the fitness defect. HCC₁ and HCC₂ were calculated by R₀ to have a fitness value of 0. 52 and 0. 45 relative to MA-S.     

SOME BIOCHEMICAL ASPECTS OF RESISTANCE TO CONTROLLED ATMOSPHERE IN LIPOSCELIS BOSTRYCHOPHILA BADONNEL (POSCOPTERA: LIPOSCELIDIDAE)*

Abstract Adults of the psocid Liposcelis bostrychophila were exposed to an atmosphere containing 35% CO₂ and 1% O₂ for 30 successive generations at 28 C and 70%–80% RH in order to select a resistant strain to controlled atmosphere (CA). At the 30th generation the resistance factor (LT₅₀ for selected generation / LT₅₀ for non-selected generation) reached to 5. 6-folds. The results of biochemical assays showed that the activities of carboxylesterase (CarE) and superoxide dismutase (SOD) in vitro increased considerably from generation to generation during the selection process, and they were closely correlated with the resistance levels. At the 30th generation, the CarE and SOD activities in the resistant strain to CA (CA-R) were 4. 06-and 5. 22-folds as much as those in the susceptible strain to CA (CA-S), respectively. Exposure to CA resulted in decrease in CarE activity; however, the decreasing range for CA-S was significantly greater than that for CA-R. CA had induction effect on SOD within short time, but for CA-R the induction time was longer and activity induced was higher than CA-S. Catalase (CAT) activity was also raised with the resistance development, but no statistical relationship was found between CAT activity and CA resistance. No significant difference of both acid phosphatase (ACP) and alkaline phosphatase (ALP) was found in CA-R and CA-S during the selection process. Peroxidase (POD) activity was not detected in L. bostrychophila. These suggest that the major mechanism responsible for CA resistance appears to be the enhanced CarE and SOD activities, and probably CAT plays an additionary role to adopt low O₂ concentration in CA resistance.     

Molecular characterization of two nicotinic acetylcholine receptor subunits from Liposcelis bostrychophila Badonnel (Psocoptera: Liposcelididae)

Two nicotinic acetylcholine receptor (nAChR) subunit genes, Lbα1 and Lbα8, were isolated and characterized from psocid, Liposcelis bostrychophila Badonnel, using the rapid amplification of cDNA ends (RACE) technique. They are the first two nAChR family members isolated from the insect order of Psocoptera. The full‐length cDNAs of Lbα1 (GenBank accession number: EU871527) and Lbα8 (EU871526) consist of 2,025 and 1,763 nucleotides, respectively, and an open reading frame of 1,644 and 1,608 bp encoding 547 and 535 amino acid proteins, respectively. Both genes have typical features of nAChR family members, though they share only 56% identity in amino acid sequence. The dendrogram generated by the MEGA 3.1 program shows that the protein deduced by Lbα1 had the closest phylogenetic relationship to Agamα1 from Anopheles gambiae and Amelα1 from Apis mellifera, and Lbα8 shares the highest identity with Agamα8 from An. gambiae and Amelα8 from A. mellifera. Quantitative real‐time PCR analysis showed that Lbα1 was expressed 2.03–6.54‐fold higher than Lbα8 at the different developmental stages of L. bostrychophila. The highest expression levels of Lbα1 and Lbα8 were both detected at adult stage and the lowest were at the third and fourth nymphal stages, respectively. There was a stable and relatively low expression level for Lbα1, whereas there was a descending expression pattern for Lbα8 in the 1st through the 4th nymphal stadia. © 2009 Wiley Periodicals Inc.     

四种杀虫剂对两种书虱羧酸酯酶和乙酰胆碱酯酶的抑制作用

选用有机磷类杀虫剂(敌敌畏、毒死蜱、对氧磷)和氨基甲酸酯类杀虫剂(丁硫克百威),通过生物测定(药膜法)和生化测定(比色法)比较了嗜卷书虱和嗜虫书虱对所选药剂的敏感差异性。根据LC50可知嗜虫书虱对所选药剂比嗜卷书虱敏感。离体酶活性分析结果显示嗜卷书虱和嗜虫书虱的羧酸酯酶只对敌敌畏敏感,且嗜卷书虱比嗜虫书虱更敏感;4种药剂对乙酰胆碱酯酶均有强烈的抑制作用,同样是嗜卷书虱比嗜虫书虱敏感。乙酰胆碱酯酶的动力学研究结果和离体酶活性测定相一致。聚丙烯酰胺凝胶电泳分析显示,4种杀虫剂离体条件下对2种书虱的酯酶同工酶的抑制能力有明显差异,其中敌敌畏的抑制力最强;但对不同同功酶的抑制趋势(对大分子的抑制似乎较强)是一致的。酶的敏感性分析结果与生测结果比较表明,2种书虱的耐药力差异与其乙酰胆碱酯酶和酯酶对药剂的敏感性无关。如要弄清耐药力机制,需做进一步研究。