Reproductive pattern and population dynamics of aphids having sterile soldier caste.

在日本冲绳和鹿儿岛研究了两种具有不育兵型的竹蚜-高淳拟网蚜（Pseudoregma koshunensis）和竹蚜（P.bambucicola）的不育兵产生格局和种群动态。主要结果如下：（1）高淳拟步甲雌虫首先产下正常（拟生殖）幼虫，其次产下拟步甲型幼虫。这种模式与其他真社会性昆虫有很大不同，所有这些昆虫都首先产生工蜂，其次才产生生殖体。(2)在鹿儿岛，竹生拟步行虫的个体数量从8月开始增加，10月达到高峰，然后减少，7月几乎为零。士兵的比例在10月和11月最高（约。20%），3月份下降至10%，5月至7月期间接近0%。另一方面，在冲绳，从6月开始增加，在7月或8月达到高峰，然后减少。这个数字在12月非常低，在2月和3月几乎为零。士兵比例在秋季最高，但即使在秋季也远低于鹿儿岛（通常低于5%）。(3)鹿儿岛和冲绳竹类种群动态不同的原因可能是两个地区竹类生长季节不同。(4)在冲绳种群中，正常幼虫和士兵型幼虫之间的形态差异不明显，而鹿儿岛种群中的差异明显。这一事实和士兵比例的差异表明两个菌株之间存在某些遗传差异。

Pattern of production of sterile soldiers and population dynamics of two species of bamboo aphids, pseudoregma koshunensis and P.bambucicola, having sterile soldier caste, were studied in Okinawa and Kagoshima. Major results are as follows :(1) Virginoparous females of P.koshunensis first laid normal (to-be-reproductive) larvae and secondly soldier-type larvae. This pattern is quite different from other eusocial insects, all of which produce workers first and to-be-reproductives secondly. (2) In Kagoshima, the number of P.bambucicola individuals began to increase from August, reached its peak in October, then decreased and became nearly zero in July. The soldier ratio was highest in October and November (ca. 20%) and decreased to 10% in March and nearly 0% during period from May to July. On the other hand, in Okinawa, the number began to increase from June, reached the peak at July or August, then decreased. The number was very low in December and became nearly zero during February and March. The soldier ratio was highest in autumn but even in autumn it was far lower than Kagoshima (usually less than 5%). (3) A reason of different population trends between Kagoshima and Okinawa might be difference of badding season of bamboos in the two areas. (4) In Okinawan populations morphological difference between normal and soldier type larvae was not clear as compared with clear difference in Kagoshima. This fact and difference in soldier ratio suggested existence of some genetic differences between the two strains.