Ehrenfeld M J, Canals M, Cattan P E
Departamento de Ciencias Biológicas Animales, Universidad de Chile, Santiago, Chile.
J Med Entomol. 1998 Sep;35(5):740-4. doi: 10.1093/jmedent/35.5.740.
Population parameters of Triatoma spinolai Porter were studied using specimens collected in the north and central region of Chile. Two cohorts of 17 and 44 first instars were maintained at a constant temperature of 28 degrees C and 70% RH. Two similar cohorts of bugs were exposed to 16-24 degrees C and 55-75% RH and maintained under a photoperiod of 14:10 (L:D) h for 16 mo. The preimaginal period ranged between 285 and 372 d under constant conditions. The lower-density cohort required 9.5 mo to reach the adult stage compared with 12.4 mo for the high-density cohort. Bugs placed under variable temperature and relative humidity conditions did not survive long. Cohorts with higher densities had similar mortality rates with greater mortality occurring in cohorts that had lower numbers of bugs. Cohorts under constant temperature and relative humidity reproduced and basic reproduction rates (Ro, intrinsic growth rate [r], and generation time [G]) were estimated. Cohorts with higher numbers of bugs had higher Ro and r, whereas values of G were similar for both groups. Apparently, 25 degrees C was a critical temperature threshold for T. spinolai and there appeared to be a minimal population density that allowed reproduction.
利用在智利北部和中部地区采集的标本，对斯氏锥蝽（Triatoma spinolai Porter）的种群参数进行了研究。两组分别由17只和44只一龄若虫组成的群体，在28摄氏度和70%相对湿度的恒定条件下饲养。两组相似的蝽类群体被置于16 - 24摄氏度和55 - 75%相对湿度的环境中，并在14:10（光照:黑暗）小时的光周期下饲养16个月。在恒定条件下，若虫前期在285至372天之间。低密度群体达到成虫阶段需要9.5个月，而高密度群体则需要12.4个月。置于温度和相对湿度可变条件下的蝽类存活时间不长。密度较高的群体死亡率相似，而数量较少的群体死亡率更高。对处于恒定温度和相对湿度条件下的群体进行了繁殖情况研究，并估算了基本繁殖率（Ro）、内禀增长率（r）和世代时间（G）。数量较多的群体Ro和r值较高，而两组的G值相似。显然，25摄氏度是斯氏锥蝽的关键温度阈值，且似乎存在一个允许繁殖的最小种群密度。
