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。

Comparison of flight muscle development, fecundity and longevity between long-winged and short-winged female adults of Velarifictorus asperses (Orthoptera: Gryllidae)

To understand the ecological significance of wing dimorphism in a cricket species, Velarifictorus asperses (Walker), the development of flight muscles and ovary, fecundity and longevity in long-winged (LW) and short-winged (SW) female adults of this cricket bred in the laboratory were compared. On the day of emergence, LW females had better-developed flight muscles than SW females, and the weight of their flight muscles was 38.68±9.15 mg and 17.53±4.44 mg, respectively. No significant difference was observed in ovary mass between LW and SW females (P>0.05), and the weight of them was 4.69±1.04 mg and 4.88±0.97 mg, respectively. Within 8 days after emergence, the weight of the LW females’ flight muscles increased 48.9%, while the weight of the SW females’ ovaries increased up to 93.5±11.7 mg, which was about 4.5 times higher than that of the LW females. The SW females were observed to reproduce earlier and had higher total number of eggs laid than the LW females, but the significant difference in number of eggs laid was only found in early adulthood (P<0.05). No significant difference was observed in longevity between the two wing forms (P>0.05). In addition, some LW females had their flight muscles histolyzed from day 12 after emergence, and the ovaries developed faster than the LW females with fully-developed flight muscles. These results suggest that a physiological trade-off between the development of flight muscles and reproductive organs existed in female V. asperses, which may cause a differentiation of life history strategy among LW and SW females, that is to say, the LW females are able to fly and the SW females benefit more in reproduction, and the histolysis of flight muscles might be a physiological signal for LW females to switch from fly to reproductive development.