食物胁迫对翅二型丽斗蟋飞行肌和繁殖发育的影响

前期研究表明,在食物充足的条件下,翅二型丽斗蟋雌成虫长、短翅型间存在着资源投入和收益的权衡关系(trade-off);而雄成虫长短翅型间不存在此类权衡关系。在自然条件下,昆虫可能遭受食物缺乏的胁迫,因而进一步就食物胁迫对丽斗蟋飞行肌和繁殖发育的影响进行了研究。结果表明,在食物胁迫的条件下,长翅雌虫仍维持飞行肌的发育,但繁殖发育受到显著的抑制;而短翅雌虫飞行肌显著降解,繁殖发育亦维持在较高水平。说明即使是营养缺乏时,其雌成虫长、短翅型也依然存在资源配置的差异,具飞行肌和繁殖发育的权衡关系。长翅雄虫飞行肌的重量与食物充足组并无显著差异,但精巢的干重显著降低;而短翅雄虫在食物胁迫条件下飞行肌显著降解,但其精巢重量与食物充足组并无显著差异。可以认为,丽斗蟋雄虫的长、短翅型间也存在飞行肌和繁殖发育的权衡关系。     

丽斗蟋翅二型雌虫飞行肌和卵巢发育间的资源分配差异

丽斗蟋Velarifictorus ornatus具有明显的翅二型现象, 长翅型与短翅型雌虫的卵巢和飞行肌存在着生理权衡。本研究分别应用蒽酮比色法、 硫代磷酸香草醛法、 考马斯亮蓝染液对羽化后10 d内两型雌虫飞行肌与卵巢内糖原、 总脂及蛋白质含量进行了定量分析。结果表明： 成虫羽化后10 d内, 两型雌虫体重无明显差异(P>0.05), 但短翅型雌虫怀卵量明显多于长翅型雌虫, 而人工脱翅能够促进长翅型雌虫怀卵量增加(P<0.05)。短翅型雌虫飞行肌内蛋白质、 糖原及总脂含量在成虫羽化后10 d内无明显变化, 但长翅型雌虫飞行肌内蛋白质在成虫羽化后3 d时达到最大值564.4±87.5 μg/♀, 糖原与总脂含量分别于羽化后第5天达到最大值85.2±21.7 μg/♀和5 284.7±1 267.4 μg/♀。然后开始下降, 各实验处理天数内, 长翅型雌虫飞行肌内蛋白质、 糖原及总脂含量都显著多于短翅型雌虫(P<0.05)。相反, 各处理天数内, 短翅型雌虫卵巢内蛋白质、 糖原及总脂含量则明显多于长翅型雌虫(P<0.05), 同时虫龄对蛋白质、 糖原及总脂在两型雌虫飞行肌与卵巢内分配也产生明显影响(P<0.05)。人工脱翅能够促进长翅型雌虫卵巢内蛋白质、 糖原及总脂含量增加, 同时诱导飞行肌内蛋白质、 糖原及总脂含量降低, 其中总脂含量在脱翅后10 d时降为2 394.9±1 461.8 μg/♀, 只有最大值的一半, 而与短翅型雌虫相似(P>0.05), 表明总脂为丽斗蟋飞行的主要能源物质。外用保幼激素Ⅲ能够促进长翅型雌虫卵巢内蛋白质、 糖原及总脂含量增加(P<0.05), 但对飞行肌内三者含量无明显影响(P>0.05), 外用早熟素Ⅰ对短翅型雌虫卵巢内蛋白质、 糖原及总脂含量亦无明显影响(P>0.05)。上述结果表明, 丽斗蟋长翅型雌虫首先将获得的资源用于发育飞行所需的飞行肌, 短翅型雌虫则首先将所获得的资源用于发育繁殖所需的卵巢, 但长翅型雌虫飞行肌与卵巢间的资源分配方式受保幼激素的影响。     

长颚斗蟋长翅和短翅型雄成虫营养物质的积累与分配差异

[目的]翅多型雄虫在繁殖方面的能量投入与雌虫相异,这种差异可能会导致雄虫飞行与繁殖权衡的生理机制发生改变.因此,本研究旨在探究翅二型长颚斗蟋Velarifictorus aspersus雄成虫在营养物质积累与分配方面是否存在飞行与繁殖的权衡关系.[方法]选取长颚斗蟋V.aspersus头幅相近的长翅和短翅型雄成虫,对羽...     

丽斗蟋翅二型雄虫食物消化能力及消化酶活性比较

【目的】丽斗蟋Velarifictorus ornatus具明显的翅二型现象,为探讨翅型分化对丽斗蟋翅二型雄虫消化能力及中肠内消化酶活性产生的影响,对长翅型与短翅型雄虫食物消化能力及中肠内消化酶活性进行了检测比较。【方法】我们采取重量营养指数测定了羽化后12 d内丽斗蟋两型雄成虫增长量、相对增长率、取食量、食物利用率、近似消化率和食物转化率。为进一步明确丽斗蟋翅二型成虫食物消化能力与中肠内消化酶活性的关系,我们采用4种专用底物测定了中肠内用于分解蛋白质、脂肪和碳水化合物的总蛋白酶、胰蛋白酶、脂肪酶和淀粉酶的活性。【结果】结果表明,丽斗蟋两型雄虫取食量、食物转化率、食物利用率与增长量均无统计差异,但中肠内消化酶活性变化规律不同。成虫羽化后4 d时,长翅型雄虫中肠内总蛋白酶与胰蛋白酶活性显著高于短翅型雄虫,相反,羽化后0 d时,短翅型雄虫中肠内总蛋白酶与胰蛋白酶活性则显著高于长翅型雄虫,而羽化后12 d时,虽然短翅型雄虫总蛋白酶活性高于长翅型雄虫,但胰蛋白酶活性在两型雄虫间并无差异。成虫羽化后0 d时,两型雄虫脂肪酶活性无差异,但无论是羽化后4 或 12 d,长翅型雄虫中肠内脂肪酶活性皆显著大于短翅型雄虫。成虫羽化后4 d时,短翅型雄虫中肠内淀粉酶活性显著高于长翅型雄虫,而羽化后0与12 d时,两型雄虫间无显著差异。【结论】丽斗蟋翅二型雄虫食物消化能力无显著差异,但羽化后不同时间,中肠内消化酶活性存在差异,该差异可能与成虫羽化后不同时期,翅二型雄虫在飞行与繁殖投资中对不同能源物质的需求有关。     

长颚斗蟋长翅和短翅型雌成虫飞行肌发育、生殖力及寿命的比较

为探讨长颚斗蟋Velarifictorus asperses (Walker)翅型分化的生态学意义, 对室内饲养获得的长翅和短翅型雌成虫飞行肌和卵巢的发育, 以及长、 短翅型雌成虫的生殖力和寿命进行了比较研究。结果表明： 羽化当日, 长翅型雌成虫飞行肌重38.68±9.15 mg, 显著高于短翅型的17.53±4.44 mg （P<0.05）; 而二者卵巢重量无显著差异（P>0.05）, 分别为4.69±1.04 mg和4.88±0.97 mg。羽化后8 d内, 长翅型雌成虫飞行肌重量增加了48.9%, 短翅型雌成虫飞行肌重量无明显增加; 而短翅型雌成虫卵巢的重量增加至93.5±11.7 mg, 约为长翅型雌成虫的4.5倍。短翅型雌成虫的产卵前期显著短于长翅型, 其早期产卵量及总产卵量亦显著高于长翅型; 而两翅型雌成虫中后期产卵量及寿命无显著差异（P>0.05）。此外, 长翅型雌成虫在羽化后12 d开始发生飞行肌的降解, 飞行肌降解个体的卵巢重量显著高于未降解个体, 与短翅型相似。结果提示, 飞行肌与生殖系统的发育之间存在资源分配的权衡关系（trade-off), 且这种资源分配的差异可能会导致长翅型与短翅型个体在生活史策略上出现分化, 即长翅型个体具有飞行能力, 而短翅型个体则在生殖方面获得更高的收益, 且飞行肌的降解可能是长翅型个体由飞行转向生殖发育的生理信号。     

环境因素对长颚斗蟋翅型分化的影响

长颚斗蟋具有明显的翅二型现象。比较长颚斗蟋不同翅型成虫的形态差异,结果表明其短翅型成虫除翅已明显退化外,与长翅型成虫并无其他形态差异。为探究环境因素与长颚斗蟋翅型分化的关系,就光周期、温度及密度对其翅型分化的影响进行了研究。结果表明,短光周期会抑制其长翅型的形成,而LD16∶8h的长光周期则促进长翅个体的分化,但非自然条件的长光周期及全明或全暗条件与上述结论并不一致。变化光周期亦会影响其翅型分化,而随着改变光周期的时间及方向的不同,影响作用亦不相同。在孵化后第20天及40天经历光周期的趋长变化会促进其长翅化;而在孵化后第20天经历光周期的趋短变化则会抑制其长翅化,第30天转移却有促进作用。此外,低温(20℃)条件诱导长颚斗蟋短翅化,高温(25℃,30℃)则促进长翅型的分化。单独饲养时,LD12∶12h与LD16∶8h条件下的若虫均羽化为短翅型成虫,当密度增加至2或5头/容器时,成虫的长翅率均明显增加,说明高密度亦是长翅型个体出现的重要诱因。     

Physiological trade‐offs between flight muscle and reproductive development in the wing‐dimorphic cricket Velarifictorus ornatus

Morphology, flight muscles, and reproductive development were compared between long‐winged (LW) and short‐winged (SW) morphs of the cricket Velarifictorus ornatus (Shiraki) (Orthoptera: Gryllidae). There was no difference in body weight and pre‐oviposition between the two morphs, but LW individuals had better‐developed flight muscles than SW individuals during and after emergence of the adult. The flight muscles at adult emergence represented 11.9% of the total body weight in the LW female and 4.9% in the SW female. In addition, the weight of the flight muscle of LW females increased by 50% during the first 5 days, whereas the flight muscle of the SW variant increased only slightly after adult emergence. The process of oviposition in LW, SW, and de‐alated females varied: SW females produced more eggs at the early stage than LW females, but de‐alation could shorten the time until the peak of egg laying and caused histolysis of flight muscles of LW females. There was no significant difference in total egg production between the above three groups. In the male, unlike the female, the accessory glands of the two wing morphs enlarged continuously at the same rate. There was no difference between the two wing morphs in the mass of the testes during the first 7 days after adult emergence.     

沙蟋飞行肌中保幼激素滴度的昼夜节律

沙蟋Gryllus firmus是一种翅多型性的昆虫, 是研究种内迁飞和生殖调控的模式生物。本研究应用高效液相色谱仪（HPLC）、 气相色谱-质谱联用仪(GC-MS)对沙蟋长翅（有飞行能力）和短翅（无飞行能力）雌虫飞行肌内保幼激素（juvenile hormone, JH）和脂肪酸进行了定性定量分析。结果表明： 在温度28℃, 光周期16L∶8D条件下, 第5和第7日龄的沙蟋长翅雌虫飞行肌中JH的滴度具有明显的昼夜节律, 在飞行前（即关灯前）4 h, JH的滴度分别由386.52±68.40 ng/g和630.36±37.26 ng/g增加至1 327.53±277.98 ng/g和1 685.77±143.95 ng/g, 与短翅型SW相比分别增加了约3.4倍与2.7倍 (P＜0.05)。而相同日龄的短翅雌虫及第1日龄的两型雌虫均无明显的节律变化。进一步在第5和7日龄的长翅雌虫中发现了一个16C的脂肪酸--14-甲基十五烷酸, 也具有节律变化且与JH节律出现的时间相吻合, 而在无飞行能力的沙蟋中没有发现这种现象。实验还证明JH滴度的增加和节律不是由飞行肌的重量或者飞行肌重量比的变化所致。这些发现有助于探讨和了解保幼激素对飞行调控的内在机理。     

Effects of precocene I and II on flight behaviour in Oncopeltus fasciatus, the migratory milkweed bug

Treatment of newly emerged adult Oncopeltus fasciatus with the corpus allatum inhibitors. 7-methoxy-2,2-dimethyl chromene or 6,7-dimethoxy-2,2-dimethyl chromene (preocene I and II) results in an inhibition of long-term flight (presumed migratory) behaviour in both males and females and inhibition of oögenesis in females. Treatment of reproductive females with precocene briefly stimulates flight behaviour (which ceases in such females as oviposition begins) and then subsequently inhibits it. Oviposition also ceases in such females and oöcyte resorption occurs. Topical application or injections of JH III to precocenetreated animals results in immediate restoration of the tendency to make long tethered flights while corpora cardiaca extract injections, corpora cardiaca implantation, sham implantation, sham injections and sham topical applications were ineffective in restoring prolonged flight behaviour to precocene-treated animals.Restoration of flight by JH III injection was observed within 1 hr after treatment with the hormone. These results indicate that JH is necessary for prolonged flight and presumably migratory behaviour in this species and its stimulatory effect on flight behaviour is immediate. Possible mechanisms of action of the hormone on flight behaviour are discussed.     

变化光周期对丽斗蟋(Velarifictonus ornatus)若虫发育的影响

为弄清湖南株洲丽斗蟋若虫的季节适应策略,研究了恒定及变化光周期对其若虫发育的调控。结果表明,丽斗蟋若虫发育明显受变化光周期的影响。25℃温度条件下,3个光周期条件下的若虫发育都较慢,羽化也极不整齐,长日条件(LD 16∶8h)、中间日照条件(LD 14∶10h)和短日条件(LD 12∶12h)的若虫发育历期(mean ± SD)分别为(206.2± 44.0)d、(236.6±93.3)d和(230.3±47.4)d,若虫从开始羽化到供试个体全部完成羽化所需时间分别为216、301和156d,经历短日条件的若虫转移至长日条件后能够促进其快速发育,羽化也很整齐,反方向转移则会抑制若虫发育,且羽化也不整齐。30℃温度条件下,恒定长日条件下的若虫发育明显快于短日条件,变化光周期对若虫发育的调控与25℃相类似。变化光周期对若虫发育的影响与光周期的变化方向及低龄若虫感受的光周期类型有关。丽斗蟋若虫复杂的光周期反应模式的生态意义在于调节其生活史与季节同步。     

De-alation, flight muscle histolysis, and oocyte development in the striped ground cricket, Allonemobius fasciatus

ABSTRACT. Removal of hindwings from long-winged females of the striped ground cricket, Allonemobius fasciatus , DeGeer (Gryllidae), induces flight muscle histolysis and oocyte development. Such females develop oocytes as rapidly as do short-winged forms, while intact long-winged females retain their flight muscles and develop few oocytes.
Flight muscle histolysis occurs in starved long-winged females when they are de-alated. However, such females fail to mature oocytes. Implantation of corpora allata (CA) into long-winged females results in flight muscle histolysis as well as oocyte maturation even if their hindwings remain intact, indicating that flight muscle histolysis can take place without de-alation. It is likely that the CA are responsible for both flight muscle histolysis and oocyte development, and that CA activity is enhanced by de-alation.