Dautel H, Knülle W
Institut für Zoologie, AG Angewandte Zoologie/Ökologie der Tiere, Freie Universität Berlin, Haderslebener Strasse. 9, D-12163 Berlin, Germany e-mail:
Oecologia. 1997 Dec;113(1):46-52. doi: 10.1007/s004420050352.
The occurrence of diapause and quiescence was investigated in Argas reflexus engorged larvae, nymphs I and nymphs II. For diapause experiments, larvae were maintained at five different locations: at constant 20°C long day (LD; 17 h light:7 h dark) or short day (SD; 10 h light:14 h dark), at two locations with natural photoperiod and temperature and at one location with natural photoperiod but constant 15°C. At 20°C, diapause incidence was low in physiologically young larvae, increased with larval age, and then decreased to zero in specimens of increased physiological age. This pattern, observed both at constant LD and SD, suggests that the propensity to diapause changes with the physiological age of the unfed larva. The duration of diapause decreased with increasing larval physiological age at all locations, resulting in a seasonally synchronized moulting pattern. The results suggest that A. reflexus larvae are photoperiodically sensitive both before and after feeding and that decreasing daylengths may be particularly strong inductive stimuli. The developmental zero and thermal constant of the larvae were determined as 13.24°C and 220 degree-days, respectively. Degree-day measurements revealed that larval A. reflexus may enter a diapause of different length when fed between August and December and kept at natural daylength. Development of engorged nymphs I and nymphs II, but not of larvae, was ultimatively restricted at a temperature of 37.5°C, but immediately resumed at 25°C, demonstrating the occurrence of quiescence at high temperatures. Similarly, at a low temperature of 15°C, many nymphs I and II did not develop within 58 months, but did so successfully after transfer to 25°C, without additional food intake.
对饱血的波斯锐缘蜱幼虫、一龄若虫和二龄若虫的滞育和静止现象进行了研究。在滞育实验中，将幼虫饲养在五个不同的环境中：恒定20°C的长日照（LD；17小时光照：7小时黑暗）或短日照（SD；10小时光照：14小时黑暗）条件下，在两个具有自然光周期和温度的地点，以及在一个具有自然光周期但恒定15°C的地点。在20°C时，生理上较年轻的幼虫滞育发生率较低，随幼虫年龄增加而升高，然后在生理年龄增加的样本中降至零。在恒定的长日照和短日照条件下均观察到这种模式，表明未进食幼虫的滞育倾向随生理年龄而变化。在所有地点，滞育持续时间随幼虫生理年龄的增加而缩短，从而形成季节性同步的蜕皮模式。结果表明，波斯锐缘蜱幼虫在进食前后对光周期均敏感，且日长缩短可能是特别强烈的诱导刺激。幼虫的发育起点温度和热常数分别确定为13.24°C和220度日。度日测量表明，当在8月至12月之间进食并保持自然日长时，饱血的波斯锐缘蜱幼虫可能进入不同长度的滞育。饱血的一龄若虫和二龄若虫而非幼虫的发育最终在37.5°C的温度下受到限制，但在25°C时立即恢复，表明在高温下会出现静止现象。同样，在15°C的低温下，许多一龄和二龄若虫在58个月内未发育，但转移到25°C后成功发育，且无需额外进食。
