[Objective] The objective of this study is to clarify the effect of heat stress on survival and reproduction of the female citrus red mites (Panonychus citri), and to explore the population dynamic law under high-temperature condition. [Method]The P. citri were collected from Citrus Research Institute, Chinese Academy of Agricultural Science. Mites were reared on the citrus seedlings at least for 10 generations prior to the experiments in phytotron ((25±1) ℃, 75%-80% RH, 14h﹕10h (L﹕D) photoperiod). Some female adult mites were selected to detached citrus leaves remaining 12h for oviposition. Then the females were moved, and the eggs were continuously cultured until the mite reached detonymph. Then every mite was reared on a fresh leaf disc. When the mites developed to adulthood, every female adult mite was shocked at 32, 35, 38 and 41℃ for some time in constant temperature incubator, respectively. After that the treated mites were returned to the above-mentioned phytotron, accompanied by a male adult mite for each female. Each treatment was repeated thirty times at least, 25℃ served as control. The survival and oviposition were observed every 24h until the female died, to determine the effect of heat stress on the survival and fecundity of P. citri. Data were analyzed by one-way analysis of variance (ANOVA) and Duncan multiple range test (DMRT, P<0.05) using SPSS 10.0 software.[Result]High temperature had a significant effect on life-span of female adult. The longevity became shorter with the temperature rising from 32 to 41℃ after exposed to the mentioned temperatures for 1h, respectively (P<0.001). The longevity became even shorter with the stress time elapsed. For example, when exposed to 38℃for 3h, the longevity was 9. 6d (P<0.01), and it was 5. 0d when exposed to 41℃for 3h (P<0.001). Furthermore, high temperature had an adverse effect on fecundity of female adult. The average oviposition distinctly decreased under exposure of high temperature for 1h (P<0.05), and the oviposition became fewer and fewer with the stress time elapsed, for instance, when exposed to 38℃for 3h, the average fecundity of a female distinctly decreased to 23.1eggs (P<0.001), the same case happened to 41℃(P<0.001). When the citrus red mite was exposed to 32, 35, 38 and 41℃ for 1h, respectively, the age-specific survival rate (lx) curve all had “plateau duration”, but the “plateau duration”disappeared after the female exposed to 38 and 41℃ for 3h, respectively, also, the gradient of lxcurve became abrupt with the rise of treatment temperature and extension of treatment time. The age-specific fecundity (mx ) curve showed that heat stress made the oviposition summit in advance and mx decline, especially when exposed to 38 and 41℃3h, respectively, the mx of female adult mite obviously decreased. [Conclusion]The longevity and oviposition dropped under short-time heat stress condition and the degree became even serious with the rise of treatment temperature and extension of treatment time. The exposure to heat stress had harmful effect on survival and fecundity of the female citrus red mite. This suggested that the population of P. citri could be distinctly inhibited by hot summer climate.%【目的】研究高温胁迫对柑橘全爪螨（Panonychus citri）存活及生殖的影响，揭示该螨在高温条件下的种群动态规律。【方法】柑橘全爪螨采自中国农业科学院柑橘研究所，在人工气候室饲养10代后用于试验，饲养条件为温度（25±1）℃，相对湿度75%-80%，光周期14 h﹕10 h（L﹕D），寄主植物为盆栽柑橘苗。挑取雌成螨于离体柑橘叶片上，让其产卵12 h，然后移除雌成螨，收集的卵继续饲养至后若螨时，采用叶蝶法单头饲养到成螨。将雌成螨单头分别置于32、35、38及41℃恒温培养箱中热激一定时间，然后再放回上述人工气候室条件下，每个叶碟上再放1头雄成螨，每个处理至少设30个重复，以25℃为对照。每24 h观察、计数产卵情况，直至雌成螨死亡，测定高温及作用时间对柑橘全爪螨雌成螨寿命及生殖的影响。利用SPSS 10.0对数据进行单因素方差分析（one-way ANOVA），平均数的多重比较采用Duncan multiple range test（DMRT，P＜0.05）。【结果】高温35及41℃分别胁迫柑橘全爪螨雌成螨1 h，其寿命显著缩短至10.1及8.2 d（P＜0.001）。且随胁迫时间延长，影响加剧。38℃胁迫雌成螨3 h，其寿命显著缩短至9.6 d（P＜0.01）；41℃胁迫雌成螨3 h，其寿命显著缩短至5.0 d（P＜0.001）。高温胁迫对雌成螨的生殖力也有明显影响，32、35、38及41℃分别胁迫雌成螨1 h，每雌产卵量显著下降为38.4、37.5、43.5和40.2粒（P＜0.05）；随着胁迫时间的延长，产卵量继续下降，38℃胁迫雌成螨3 h，产卵量为23.1粒（P＜0.001），41℃胁迫雌成螨3 h，产卵量显著下降至7.8粒（P＜0.001）。雌成螨分别在32、35、38及41℃下胁迫1 h，特定年龄存活率（lx）曲线均出现“平台期”，但38及41℃分别胁迫雌成螨3 h，lx曲线“平台期”消失；且随着温度升高及胁迫时间的延长，lx曲线坡度变陡。特定年龄生殖力（mx）曲线显示，高温胁迫促使产卵高峰期提前，mx下降；高温38及41℃分别胁迫雌成螨3 h，mx下降尤为明显。【结论】高温胁迫下，柑橘全爪螨雌成螨寿命缩短、lx下降、产卵数量减少及mx下降，且随着胁迫温度的升高和胁迫时间的延长，影响程度加剧，短时高温对雌成螨的存活和生殖有不利影响。夏季高温条件对柑橘全爪螨种群具有明显的抑制作用。
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