Population dynamics of Japanese male planthoppers canceling the male-killing phenomenon by symbiotic bacteria in the small brown planthopper, Laodelphax striatellus.

台湾地区小褐飞虱感染螺旋体，可导致感染雌虫所生后代的雄性死亡及性别比例偏向。我们在来自日本东部和南部的不同群体中的雌性偏向系雌性和雄性之间进行了交叉实验。在九州种群中，所有与雄性杂交的后代都只产生雌性成年后代。然而，在日本西部和东部的种群中，一些与雄性杂交的配对产生了正常性别比例的雄性后代。这一结果表明，日本西部和东部人口中的一些男性取消了螺旋体中的男性杀戮现象。

Spiroplasma infected in the small brown planthopper causes male-killing and female-biased sex ratio of progenies produced by infected females in Taiwan populations. We performed cross experiments between females of female biased lines and males in various populations from eastern and southern parts of Japan. All of the pairs crossed with males in Kyushu populations produced only female adult progenies. However, some pairs crossed with males in western and eastern Japanese populations produced male progenies at the normal sex ratio. This result suggests that male-killing phenomenon in Spiroplasma is canceled by some of males in the western and eastern Japanese populations.