稻蝗属三近缘种间的生殖隔离机制及其进化意义

通过对日本稻蝗、中华稻蝗台湾亚种和小翅稻蝗的种间交配、交配后精子传送等的研究，探讨了其生殖隔离机制及其进化意义。结果表明： 有共同分布区域的日本稻蝗与中华稻蝗台湾亚种及日本稻蝗与小翅稻蝗的交配率显著低于种内交配，即使交配也无精子的传送，存在强烈的行为隔离和完全的机械隔离。分布不重叠的中华稻蝗台湾亚种与小翅稻蝗之间，小翅稻蝗的雌虫与中华稻蝗台湾亚种雄虫的交配率显著低于种内交配，反向交配时则和种内交配率无显著差异；正反交配都能完成精子传送，显示出不对称、不完全的行为隔离，而无机械隔离的存在。分布不重叠的中华稻蝗台湾亚种与小翅稻蝗生殖隔离的进化速度慢于分布重叠的日本稻蝗与中华稻蝗台湾亚种及日本稻蝗与小翅稻蝗。

Reproductive isolation mechanisms between three Oxya species (Orthoptera:Catantopidae)

Three rice grasshoppers, Oxya japonica, O. chinensis formosana and O. yezoensis are extremely similar in morphology. Here we studied their reproduc ti ve isolation mechanisms by interspecific cross experiments. For sympatric specie s, ethological isolation was found to be strong, but not complete, in reciprocal crosses between O. japonica and O. chinensis formosana, and between O . japonica and O. yezoensis; however, even where mating had occurred there was no sperm tr ansfer. For allopatric species, asymmetric ethological isolation was apparent in crosses between O. chinensis formosana and O. yezoensis: females of O . chinensis formosana readily accepted males of O. yezoensis, but females of O. yezoensis show reluctance to males of O. chinensis formosana; howe ver, in either reciprocal cross sperms were transferred. These results supported t he conclusion that reproductive isolation evolves slower in allopatric species or populations than sympatric species or populations.