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1.
赵吕权  朱道弘 《昆虫学报》2013,56(6):622-629
为探讨丽斗蟋Velarifictorus ornatus翅二型个体飞行与生殖发育间生理权衡的内分泌控制机理, 本研究调查了外用保幼激素Ⅲ(JH-III)与早熟素Ⅰ(P-I)对丽斗蟋翅二型个体飞行肌与生殖发育的影响。结果表明: 成虫羽化后当日分别注射1, 5, 10和25 μg保幼激素7 d后, 显著促进了丽斗蟋长翅雌虫卵巢发育, 卵巢重量分别从对照组的16.8±11.4 mg/♀增加到43.9±10.7, 33.6±14.0, 56.8±7.6和 39.3±30.7 mg/♀; 但对卵巢内怀卵量无显著影响。相反, 外用保幼激素则诱发飞行肌降解, 1, 5和10 μg JH-III处理组飞行肌重量分别下降为12.9±4.7, 11.7±4.8和8.8±0.8 mg/♀, 显著低于对照组飞行肌重量(17.7±1.6 mg)。对短翅雌虫注射P-I时, 当注射的剂量超过50 μg/♀时, 能够显著抑制卵巢发育, 而低于50 μg/♀时则对卵巢发育无明显影响。外用JH-III对丽斗蟋长翅雄虫飞行肌、 精巢、 附腺的发育无明显影响; 外用P-I对短翅型雄虫精巢与附腺的发育也无明显影响。因此, 丽斗蟋翅二型雌虫与雄虫的飞行肌与生殖器官的内分泌控制机理可能存在差异。  相似文献   

2.
【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,对羽化后7 d内两型雄成虫的体重的动态变化进行了比较,利用分光光度计法测定了两型雄成虫虫体及飞行和繁殖器官内蛋白质、总脂和糖原含量。【结果】长颚斗蟋V. aspersus长翅雄成虫在羽化后前7 d内体重保持不变,而短翅雄成虫的体重显著增加。羽化当日长、短翅雄成虫体内蛋白质含量分别为46.5±2.7和42.3±1.9 mg,二者差异显著,且长翅雄成虫羽化后体内蛋白质含量的增加速率明显高于短翅雄成虫;而羽化当日两型雄成虫体内总脂含量无显著差异,但羽化后第5和7天短翅雄成虫体内总脂含量均显著高于长翅雄成虫。成虫羽化后7 d内长翅雄成虫飞行肌内蛋白质和总脂含量均显著高于短翅雄成虫,羽化当日两型雄成虫附腺内的蛋白质与总脂含量无显著差异,但从第3天开始,短翅雄成虫附腺内蛋白质和总脂含量均显著高于长翅雄成虫。【结论】 结果说明翅二型长颚斗蟋V. aspersus雄成虫体内营养物质的积累与分配方面存在飞行与繁殖的权衡关系。  相似文献   

3.
【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。  相似文献   

4.
赵吕权  朱道弘  曾杨 《昆虫学报》2012,55(9):1037-1045
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。  相似文献   

5.
曾杨  朱道弘  赵吕权 《昆虫学报》2012,55(2):241-246
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。  相似文献   

6.
沙蟋翅多型性的调控机理   总被引:1,自引:0,他引:1  
沙蟋Gryllus firmus Zera&Denno成虫的后翅有长翅和短翅2种类型,是翅多型性机理研究的极佳模式昆虫。长翅成虫从第5日龄开始迁飞,而短翅成虫的主要特点是繁殖。除了翅的表型差异外,长翅成虫的飞行肌发达,呈褐色;卵巢幼小,直到飞行停止后(大约在10d以后)才开始发育。而短翅成虫的飞行肌退化并呈乳白色;卵巢在第4日龄就发育成熟,表现为卵巢硕大。对翅多型性机理的深入研究,将有利于了解沙蟋迁飞和扩散的内在机理,为准确地预测预报该虫的发生提供重要的理论和实际依据。文章概述沙蟋翅多型性与外界环境的相互关系,以及体内生化代谢和内分泌激素等的变化对该虫迁飞和生殖的影响和作用,进而探讨翅多型的遗传机制和进化意义等问题。  相似文献   

7.
王娟  朱道弘  曾杨 《生态学报》2014,34(22):6606-6612
曲脉姬蟋Modicogryllus confirmatus Walker具有明显的翅二型现象。为探究环境及遗传如何影响曲脉姬蟋亚热带种群的翅型分化,对饲养于不同光周期、温度和密度条件下若虫羽化后的翅型比进行了调查,并对长、短翅型蟋蟀进行了3代遗传筛选和杂交试验,研究了光周期、温度、种群密度和遗传对曲脉姬蟋广西种群翅型分化的影响。结果表明:光周期和种群密度对曲脉姬蟋的翅型分化均无影响,而温度对其翅型分化具有调控作用。正常范围内的温度变化(25℃、30℃)对其翅型分化无显著影响,而35℃的极高温则显著降低曲脉姬蟋的长翅率,说明其翅型分化并不是对季节变化的适应,而高温胁迫可引起短翅化。对不同翅型进行了3代筛选,结果表明,往短翅型选拔会引起雌、雄虫的短翅率都明显下降,而往长翅型选拔时,雌、雄虫的短翅率均维持在极低水平;不同亲本组合的后代间的长翅率有差异,说明曲脉姬蟋的翅型分化可能受多基因调控。  相似文献   

8.
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。  相似文献   

9.
曾杨  朱道弘  赵吕权 《生态学报》2010,30(21):6001-6008
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。  相似文献   

10.
利用石蜡切片的方法,观察并比较了褐飞虱Nilaparvata lugens (Stal)长翅型和短翅型纯系各龄若虫及成虫的翅芽和间接飞行肌的发育情况。发现在4龄的第8h以后间接飞行肌就开始分化,长翅型若虫的间接飞行肌正常发育而短翅型若虫间接飞行肌的发育则被抑制。在5龄初始时方可明显观察到翅芽分化,短翅型若虫前翅芽细胞增殖速度明显慢于长翅型,并且其后翅芽停止发育。本文还比较了长翅型雌、雄性个体之间间接飞行肌的发育情况。  相似文献   

11.
Flight dimorphism has been considered to result from a balance of costs and benefits between flight capability and reproduction. The validity of the hypothesis, however, has been challenged recently. In this study, we examined the effect of flight time on trade-off between flight capability and reproductive development in Velarifictorus aspersus and we found that flight of 5 min did not promote reproductive development of long-winged (LW) adults, but flight of 30, 60, or 120 min could promote reproductive development both in female and male crickets. The results indicate that flight time may serve as a signal for LW V. aspersus to switch from migration to reproduction, and trade-off between flight ability and reproduction may be attenuated when flight time reaches a critical threshold. In addition, rapid reproductive development occurred before dealation when LW insects were allowed to fly for 30 min, which indicates that flight may influence reproductive development directly. Food consumption of short-winged adults was significantly higher than that of unflown LW adults or LW adults with 5 min flight, but similar to that of LW adults with 30, 60, or 120 min flight, suggesting that difference of reproductive development may be positively correlated with their food consumption.  相似文献   

12.
Although all Tuberculatus aphids possess wings, some species associated with ants exhibit extremely low levels of dispersal compared with those not associated with ants. Furthermore, phylogenetic interspecific comparisons find significantly higher wing loading (i.e. higher ratio of body volume to wing area) in ant‐attended species. This observation indicates that ant‐attended species may allocate more of their body resources to reproductive traits (i.e. embryos) rather than flight apparatus (i.e. wings, flight muscle and lipid). The present study focuses on two sympatric aphid species and aims to investigate the hypothesized trade‐off in resource investment between fecundity and the flight apparatus; specifically, the ant‐attended Tuberculatus quercicola (Matsumura) and non‐attended Tuberculatus paiki Hille Ris Lambers. Species differences are compared in: (i) morphology, (ii) embryo production, (iii) triacylglycerol levels and (iv) wing loading and flight muscle. The results show that T. quercicola has a larger body volume, higher fecundity and higher wing loading compared with T. paiki, which has a smaller, slender‐shaped body, lower fecundity and lower wing loading. No significant difference is found between the species with respect to the percentage of triacylglycerol content in dry body weight. The flight muscle development is significantly lower in T. quercicola than in T. paiki. These results indicate that the additive effect of higher wing loading and the lower amount of flight muscle development in T. quercicola may increase the physical difficulty of flight, and hence be responsible for its lower dispersal ability. The trade‐off between fecundity and dispersal documented in wing‐dimorphic insects may therefore be applicable to T. quercicola, which has fully developed wings.  相似文献   

13.
Flightlessness in insects is generally thought to have evolved due to changes in habitat environment or habitat isolation. Loss of flight may have changed reproductive traits in insects, but very few attempts have been made to assess evolutionary relationships between flight and reproductive traits in a group of related species. We elucidated the evolutionary history of flight loss and its relationship to evolution in food habit, relative reproductive investment, and egg size in the Silphinae (Coleoptera: Silphidae). Most flight-capable species in this group feed primarily on vertebrate carcasses, whereas flightless or flight-dimorphic species feed primarily on soil invertebrates. Ancestral state reconstruction based on our newly constructed molecular phylogenetic tree implied that flight muscle degeneration occurred twice in association with food habit changes from necrophagy to predatory, suggesting that flight loss could evolve independently from changes in the environmental circumstances per se. We found that total egg production increased with flight loss. We also found that egg size increased with decreased egg number following food habit changes in the lineage leading to predaceous species, suggesting that selection for larger larvae intensified with the food habit change. This correlated evolution has shaped diverse life-history patterns among extant species of Silphinae.  相似文献   

14.
High population density and nutrition restriction can lead to phase variation in morphology and development, and subsequently induce changes in the reaction norms of adult flight in migrant insects. However, response of migratory propensity to such stress in Endopterygote insects, especially in several species of Lepidoptera, remains unclear. In this study, larval and adult developmental responses to crowding and food stress were investigated in the migratory moth, Cnaphalocrocis medinalis (Guenée). A high larval rearing density significantly reduced pupal mass, survival rate and female fecundity. Larvae developed rapidly under crowding conditions, and time to pupation was 2 days earlier than individuals reared alone. By contrast, short‐term starvation and associated compensatory growth prolonged larval duration by 3–4 days and pupal duration by 1–2 days. It also reduced the pupal mass, but showed no detectable effects on female reproductive performance. Both sexes had similar development strategies; however, females seemed to be more sensitive to crowding and food shortage than males. A positive effect was expected if such stress factors acted as cues that triggering a behavioural or physiological shift to a distinct migratory phase. To the contrary, we found no proof that crowding and starvation caused maturation delay in female reproductive development. All treatments did not significantly increase female pre‐oviposition period. Therefore, we concluded that life developmental responses to crowding and food shortage in this species were different. Adult migration propensity was not enhanced under such stress conditions during the larval phase.  相似文献   

15.
Phenotypic characters may covary negatively because they are in a trade-off or positively because they contribute to a single function. Genetic correlations can be used to test the validity and generality of these functional relationships by indicating the level of genetic integration and checking the conditions under which they are expressed. Phenotypic correlations indicate that there is a widespread trade-off between flight capability and early fecundity in insects. Different wing morphs (long and short wing) are thought to have a suite of reproductive and flight capability traits. In a half-sib mating experiment, we estimated phenotypic relationships between two flight-capability-related characters (flight muscle condition, wing morph) and two components of early fecundity (number of eggs in the ovaries, number of eggs laid), as well as genetic correlations relating wing morph and both components of fecundity in the wing-dimorphic cricket, Gryllus firmus. The number of eggs in the ovaries and the number of eggs laid were negatively correlated phenotypically and genetically with wing length morph (i.e., long wings associated with low fecundity). Both fecundity characters differed between wing morphs, but only if flight muscle was present and not histolyzed. The phenotypic and genetic correlations between fecundity characters were not significant. This suggests that the phenotypic relationship between ovary development and eggs laid is complex, they are not genetically integrated, and they may evolve independently. However, both early fecundity characters are functionally and genetically integrated within the trade-off to a similar degree. Finally, the trade-off affects early fecundity of both wing morphs suggesting that the functional relationship depends on flight muscle size. Received: 1 December 1998 / Accepted: 20 May 1999  相似文献   

16.
Migration by flight is an important component of the life cycles of most insects. The probability that a given insect will migrate by flight is influenced by many factors, most notably the presence or absence of fully-developed wings and functional flight musculature. Considerable variation has also been reported in the flight propensity of fully-winged individuals with functional flight musculature. We test the hypothesis that these components of migratory tendency are genetically correlated in a wing-dimorhic cricket, Gryllus firmus. Flight propensity and condition of the dorsal longitudinal flight muscles (DLM) are examined in fully-winged (LW) crickets from lines selected for increasing and for decreasing %LW, as well as from unselected control lines. Increased %LW is found to be associated with increased flight propensity among individuals with intact DLM, and with retention of functional DLM. The opposite is true for lines selected for decreased %LW. These results indicate both phenotypic and genetic correlations among behavioral, physiological, and morphological traits determining migratory tendency. We propose that these correlations may result from the multifunctional role of juvenile hormone, which has been reported to influence wing development, flight muscle development and degeneration, and flight propensity. Finally, we discuss the potential influence of genetic correlations for migratory traits on the evolution and maintenance of migratory polymorphisms in insects.  相似文献   

17.
Evolution of Flight in Insects   总被引:1,自引:0,他引:1  
Norberg, R. Å. (Department of Zoology, University of Gothenburg, Göteborg, Sweden.) Evolution of flight in insects. Zool. Scripta 1 (6): 247–250, 1972.–Two hypotheses on the origin of flight in insects are discussed. 1. Gliding hypothesis. If wings and flight originated in ca. 1 cm large, or larger, insects, a leaping type seems to be a more probable candidate than a non-leaping one, since the former type has, with certainty, a high frequency of voluntary air excursions, during which any extensions come into play. Furthermore, it may attain the equilibrium gliding speed by jumping, and need not, if arboreal, lose any height on a steep initial fall to gain speed. 2. Floating hypothesis. The hypothesis presented here is a modified version of that put forward by Wigglesworth in 1963. It is suggested that wings may have originated in very small insects as thin dorsolateral, fringed extensions (like the wings of the smallest flying insects) acting as viscous drag producers, enabling the insects to float in the air with a very slow sinking speed and to be dispersed passively over long distances by thermal convection currents. Mov-ability of the wings would have increased practicability on the ground, and selection pressure for this could have brought about preadaptation for active flapping flight. Monophyly versus convergence of insect wings of conventional type (aerofoil function) is discussed briefly.  相似文献   

18.
Early Metamorphosis Insertion Technology (EMIT) is a novel methodology for integrating microfabricated neuromuscular recording and actuation platforms on insects during their metamorphic development. Here, the implants are fused within the structure and function of the neuromuscular system as a result of metamorphic tissue remaking. The implants emerge with the insect where the development of tissue around the electronics during pupal development results in a bioelectrically and biomechanically enhanced tissue interface. This relatively more reliable and stable interface would be beneficial for many researchers exploring the neural basis of the insect locomotion with alleviated traumatic effects caused during adult stage insertions. In this article, we implant our electrodes into the indirect flight muscles of Manduca sexta. Located in the dorsal-thorax, these main flight powering dorsoventral and dorsolongitudinal muscles actuate the wings and supply the mechanical power for up and down strokes. Relative contraction of these two muscle groups has been under investigation to explore how the yaw maneuver is neurophysiologically coordinated. To characterize the flight dynamics, insects are often tethered with wires and their flight is recorded with digital cameras. We also developed a novel way to tether Manduca sexta on a magnetically levitating frame where the insect is connected to a commercially available wireless neural amplifier. This set up can be used to limit the degree of freedom to yawing “only” while transmitting the related electromyography signals from dorsoventral and dorsolongitudinal muscle groups.  相似文献   

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