孤雌产雌生殖品系松毛虫赤眼蜂产卵强度 对Wolbachia诱导的其生殖表型的影响

【目的】松毛虫赤眼蜂Trichogramma dendrolimi是一种用于鳞翅目害虫生物防治的重要卵期寄生蜂。本研究旨在明确孤雌产雌生殖品系松毛虫赤眼蜂的产卵强度对其体内Wolbachia滴度及Wolbachia诱导的孤雌产雌生殖表型的影响。【方法】在室内调查了3个处理组松毛虫赤眼蜂雌蜂不同产卵强度(每日仅1 h供寄主卵、隔日24 h供寄主卵和持续供寄主卵)对其生物学指标包括7 d内逐日子代雄性比、逐日产卵量、累积子代雄性比和累积产卵量的影响;采用实时荧光定量PCR方法检测未产卵雌蜂(对照)以及每日仅1 h供寄主卵和持续供寄主卵的雌蜂体内Wolbachia滴度(wsp基因拷贝数)。【结果】持续供寄主卵的雌蜂累积子代雄性比显著高于每日仅1 h供寄主卵,但与隔日24 h供寄主卵相比无显著差异。3个处理组雌蜂逐日子代雄性比随日龄的增加均显著上升,其中持续供寄主卵的处理组的上升幅度最高。持续供寄主卵的雌蜂累计产卵量显著高于每日仅1 h供寄主卵和隔日24 h供寄主卵。3个处理组雌蜂逐日产卵量随日龄的增加而显著下降,其中持续供寄主卵的处理组的下降幅度最高。未产卵的雌蜂体内Wolbachia滴度显著高于持续提供寄主卵的雌蜂体内的滴度,但与每日仅1 h供寄主卵的雌蜂体内的滴度相比无显著差异。【结论】结果说明,当松毛虫赤眼蜂雌蜂产卵不受限制时,Wolbachia滴度减少,宿主孤雌产雌表型减弱;而限制雌蜂产卵有助于维持Wolbachia滴度和宿主孤雌产雌表型。研究结果为认识Wolbachia与宿主赤眼蜂之间的互作以及应用孤雌产雌生殖品系松毛虫赤眼蜂防控害虫提供一定的参考。     

两种抗生素对携带Wolbachia的短管赤眼蜂生殖模式的影响

携带有Wolbachia的短管赤眼蜂为完全的产雌孤雌生殖。前期的实验表明,利用四环素对携带有Wolbachia的短管赤眼蜂进行除菌处理,但结果并不能获得100%恢复孤雌产雄。本实验拟用环丙沙星与磺胺嘧啶这两种抗生素对携带有Wolbachia的短管赤眼蜂进行除菌效果筛选。实验分3组药剂处理,分别为使用环丙沙星、磺胺嘧啶及环丙沙星与磺胺嘧啶1:1混配液进行除菌处理。各组实验分别进行浓度为0.1 mg/mL、1.0 mg/mL和10.0 mg/mL 3个浓度处理。以无抗生素蜂蜜水处理作为实验对照组。分别检测、记录各处理的F0 - F1代的寄生卵量,F1 - F2代羽化个体数、雌雄个体数,雌雄相嵌体的个体数。结果表明：磺胺嘧啶对短管赤眼蜂的F0代产卵量降低,但F1代恢复产卵量;仅有0.1 mg/mL环丙沙星与磺胺嘧啶1:1混配液对短管赤眼蜂F2代的卵羽化率具有抑制作用,其它的处理与对照组结果无差异。环丙沙星处理后的携带Wolbachia的短管赤眼蜂没出现雄性后代,浓度为0.1 mg/mL环丙沙星与磺胺嘧啶1:1混配液处理在F2代出现了雌雄相嵌体。浓度为1.0 mg/mL和10 mg/mL的环丙沙星与磺胺嘧啶1:1混配液处理和磺胺嘧啶处理在F2代出现了完全雄性后代。使用磺胺嘧啶处理携带Wolbachia的短管赤眼蜂,可更方便快捷获得100%雄性后代。     

卷蛾赤眼蜂体内共生Wolbachia对寄主产雌孤雌生殖行为的影响

在30℃的条件下,连续饲养卷蛾赤眼蜂 Trichogramma cacoeciae Marchall 10代,观察每代蜂的生物学特性,并进行Wolbachia的wsp基因的分子检测,以研究卷蛾赤眼蜂产雌孤雌生殖行为与其体内共生菌Wolbachia的关系.结果表明,高温下卷蛾赤眼蜂体内的Wolbachia被抑制,4代以后wsp基因的PCR检测结果变为阴性;同时赤眼蜂的产雌孤雌生殖行为的改变程度也随着世代的增加呈递增趋势.这显示卷蛾赤眼蜂的产雌孤雌生殖行为与其体内的共生菌Wolbachia具有一定程度的相关性.     

卷蛾赤眼蜂体内共生菌Wolbachia对寄主产雌孤雌生殖行为的影响

在30℃的条件下,连续饲养卷蛾赤眼蜂Trichogramma cacoeciaeMarchall10代,观察每代蜂的生物学特性,并进行Wolbachia的wsp基因的分子检测,以研究卷蛾赤眼蜂产雌孤雌生殖行为与其体内共生菌Wolbachia的关系。结果表明,高温下卷蛾赤眼蜂体内的Wolbachia被抑制,4代以后wsp基因的PCR检测结果变为阴性;同时赤眼蜂的产雌孤雌生殖行为的改变程度也随着世代的增加呈递增趋势。这显示卷蛾赤眼蜂的产雌孤雌生殖行为与其体内的共生菌Wolbachia具有一定程度的相关性。     

短期高温对感染Wolbachia的松毛虫赤眼蜂发育和繁殖的影响

感染了沃尔巴克氏体Wolbachia的松毛虫赤眼蜂Trichogramma dendrolimi Matsumura营孤雌产雌生殖方式,但高温可能影响这一特性。为了模拟该赤眼蜂在田间遇到短期高温后的受影响情况,研究了柞蚕卵繁殖的Wolbachia感染了Wolbachia的松毛虫赤眼蜂孤雌产雌品系,于蛹中期和蛹后期经历6h32,35,38℃高温单次冲击处理,对当代羽化出蜂率、单卵出蜂数、单卵雌蜂率、寿命4个指标和处理子代羽化出蜂率、有效繁殖个体、单卵出蜂数、单卵雌蜂率4个指标的影响。结果表明,短期高温刺激会对孤雌产雌的松毛虫赤眼蜂产生不利影响,尤其是38℃高温不利影响明显,主要表现在羽化出蜂率和单卵出蜂数两指标明显降低;高温冲击对子代蜂各指标影响不明显。2代赤眼蜂均未有雄峰出现,表明短期高温冲击不能对Wolbachia调控其宿主生殖方式的作用产生影响。     

短时极端高温对松毛虫赤眼蜂成虫致死作用及子代适合度的影响

极端高温天气事件在高产作物种植区频繁发生,潜在影响了寄生蜂对害虫的防控能力.为明确短时极端高温对松毛虫赤眼蜂Trichogramma dendrolimi Matsumura成虫致死作用及子代发育适合度的影响,本研究模拟夏季田间最高气温,以42℃高温处理松毛虫赤眼蜂成蜂0.5h和1 h,统计并观测了各处理条件下母代蜂致死率、繁殖力、子代蜂寿命、羽化率、性比和畸形率.结果显示:短时高温对松毛虫赤眼蜂有致死作用,表现为雌、雄蜂直接死亡及子代羽化率降低.42℃处理1 h,雌、雄蜂死亡率分别为40.28％和58.25％.短时极端高温导致松毛虫赤眼蜂子代适合度降低,表现为雌蜂寿命缩短、繁殖力下降,子代蜂畸形率增加及子代蜂雄性比上升.结果表明,短时极端高温对松毛虫赤眼蜂适合度产生负面影响,降低种群数量.本研究为夏季田间释放松毛虫赤眼蜂提供重要理论依据.     

不同温度下松毛虫赤眼蜂孤雌产雌品系和两性生殖品系对米蛾卵的寄生功能反应

赤眼蜂部分蜂种或品系受Wolbachia侵染营孤雌产雌生殖。 通过室内试验分析了在4个恒温（20, 25, 30和35℃）下松毛虫赤眼蜂Trichogramma dendrolimi两性生殖品系和孤雌产雌品系对米蛾Corcyra cephalonica卵的寄生功能反应, 旨在比较不同温度两品系的寄生功能反应差异, 评价孤雌产雌品系在生物防治中的应用潜力。 结果表明： 松毛虫赤眼蜂两个品系对米蛾卵寄生作用均随寄主密度的增加而增大;随温度的升高松毛虫赤眼蜂两品系的功能反应类型由Ⅲ型改变为Ⅱ型。孤雌产雌品系以30℃的处置时间最短(0.0207 d), 最大日寄生量为48.31粒卵, 其次是25℃, 35℃最小;两性生殖品系以25℃的处置时间最短(0.0188 d), 最大日寄生量为53.08粒卵, 其次是30℃, 20℃最小; 松毛虫赤眼蜂两品系的寄生功能反应存在显著差异, 30℃下孤雌产雌品系为Ⅱ型功能反应而两性生殖品系为Ⅲ型。 从处置时间来看, 20℃时两品系无显著性差异(P≥0.05), 在25℃和35℃孤雌产雌品系寄生米蛾卵时花费的时间显著长于两性生殖品系(P<0.05), 而30℃却相反。 可见, 寄主密度、 温度和Wolbachia影响松毛虫赤眼蜂功能反应。     

松毛虫赤眼蜂孤雌产雌品系田间控害作用研究

【目的】为明确感染Wolbachia的松毛虫赤眼蜂孤雌产雌品系对亚洲玉米螟的防治效果。【方法】2012和2013连续两年于沈阳地区玉米田间释放松毛虫赤眼蜂孤雌产雌品系和两性生殖品系。【结果】2012年孤雌产雌品系对1代亚洲玉米螟卵寄生效果为66.39%,对2代玉米螟卵寄生效果为69.53%,与对照(松毛虫赤眼蜂两性品系)相比无显著差异(分别为56%,79.73%)(P≥0.05),2013年孤雌产雌品系对1代亚洲玉米螟卵寄生效果为56.20%,对2代玉米螟卵寄生效果为82.10%,与对照相比无显著差异(分别为52.24%,75.71%)(P≥0.05)。收获前期剖杆结果表明,2012年孤雌产雌品系及对照对玉米螟的防治效果分别为22.50%、27.50%,2013年分别为38.28%、21.09%,连续两年的防治效果无显著差异(P≥0.05)。【结论】从田间试验结果可以看出,孤雌产雌松毛虫赤眼蜂品系可取得与生产用两性松毛虫赤眼蜂品系同期的防治效果,且孤雌产雌松毛虫赤眼蜂在种群增长速率、降低规模化培养成本、低密度种群下进入新生境并建立种群等方面都要优于正常松毛虫赤眼蜂品系,因此其具有很好的生防应用效果。     

Wolbachia对赤眼蜂的性别调控机制及生理影响

沃尔巴克氏体(Wolbachia)是广泛分布于节肢动物生殖组织内的一类共生细菌。它们通过共生诱导宿主赤眼蜂的产雌孤雌生殖,在生物防治上具有重要意义。文章概述了Wolbachia在赤眼蜂中的分布状况,对赤眼蜂的性别调控机制,在赤眼蜂种群中的传播及限制因素,以及对赤眼蜂适合度的影响。     

温度通过影响Wolbachia滴度调控赤眼蜂生殖方式

【目的】揭示温度对宿主体内Wolbachia滴度及其调控宿主生殖作用的影响。【方法】以感染Wolbachia且营孤雌产雌生殖的食胚赤眼蜂Trichogramma embryophagum为对象,在22,25,28和31℃4个梯度温度下连续培养5代,观察生殖方式、性比等生物学特性;采用实时荧光定量PCR以Wolbachia特异基因——外膜蛋白基因(wsp)、二磷酸果糖醛缩酶基因(fbp A)和酰胺转移酶基因(gat B)为靶标对内生菌进行定量分析。【结果】22和25℃条件下连续培养5代,食胚赤眼蜂生殖方式均未发生改变(无雄蜂出现),且5代赤眼蜂群体Wolbachia滴度没有明显差异;28℃下,食胚赤眼蜂在F3代开始有雄蜂出现,至F5代雄蜂比例明显增多,且体内Wolbachia滴度在F2代开始下降,至F5代显著下降;31℃下,F2代即有雄蜂出现,至F5代已经恢复成产雄孤雌生殖,体内Wolbachia滴度也在F2代开始下降,F3代开始显著降低,到F5代Wolbachia滴度极小甚至检测不到。【结论】高温可改变营孤雌产雌生殖赤眼蜂的生殖方式及体内Wolbachia滴度,且随着处理代数的增加以及温度的升高作用显著,即高温对营孤雌产雌生殖赤眼蜂生殖方式改变程度与其体内Wolbachia滴度呈负相关。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.     

（鱼句）亚科花（鱼骨）型鱼类骨骼系统的比较

对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。