恒温和变温驯化对大蟾蜍蝌蚪热耐受性的影响  

The effects of constant and variable thermal acclimation on thermal tolerance of the common giant toad tadpoles( Bufo gargarizans)

作　　者：王立志[1,2] 

机构地区：[1]西北大学生命科学学院,西安710069 [2]陕西学前师范学院生物科学与技术系,西安710061

出　　处：《生态学报》2014年第4期1030-1034,共5页Acta Ecologica Sinica

基　　金：陕西省自然科学基金资助项目(2010JM3013);陕西省教育厅自然科学基金资助项目(2013JK0738);陕西学前师范学院科研基金资助项目(2012KJ007)

摘　　要：为了解大蟾蜍蝌蚪(Bufo gargarizans)的热适应性并验证最适性模型,将大蟾蜍蝌蚪分别在10、15、20℃和25℃4个不同恒温下及15.76-5.42℃的变温下驯养2周,利用温度梯度装置观察记录其最适温度、最高逃避温度和最高致死温度。结果表明,经过在10、15、20℃和25℃四个恒温及在15.76—5.42℃的变温下驯化,大蟾蜍蝌蚪的最适温度分别为(14.8±2.9),(17.2±3.8),(18.1±3.5),(19.6±2.5)和(15.8±2.2)℃;最高逃避温度分别为(27.6±1.9),(31.3±1.3),(32.5±0.8),(33.9±1.0)和(31.6±1.3)℃;最高致死温度分别为(32.9±1.6),(36.5±1.0),(37.9±0.9),(38.8±1.1)和(37.2±1.3)℃。驯化温度对大蟾蜍蝌蚪的最适温度、最高逃避温度和最高致死温度都有显著影响(P<0.001)。驯化温度对大蟾蜍蝌蚪最适温度产生的影响比最高逃避温度和最高致死温度的小。温度的昼夜变化,都会呈现两峰或三峰分布,双峰环境实际上是具有同一标准误差的两个正常分布的混合体,这两个正常分布被一个峰间距所隔离。最适性模型预测:当呈双峰分布的温度的峰间距为17℃时,动物将出现3个适合度峰值。研究结果支持最适性模型。In order to testify the Optimality models, preferred temperature, high avoidance temperature and high lethal thermal maxima of the common giant toad tadpoles were measured using thermal gradient apparatus. Tadpoles of this species were acclimated at different temperatures （10 ℃, 15 ℃, 20 ℃, 25 ℃ and 15.76-5.42 ℃） for two weeks. The results showed that the preferred temperature of the common giant toad tadpoles were （17.2±3.8）, （18.1±3.5）, （19.6±2.5） and （15.8±2.2） ℃; the high avoidance temperature of the common giant toad tadpoles were （27.6±1.9）, （31.3±1.3）, （32.5±0.8）, （33.9±1.0） and （31.6±1.3） ℃; the high lethal temperature of the common giant toad tadpoles were （32.9±1.6）, （36.5±1.0）, （37.9±0.9）, （38.8±1.1） and （37.2±1.3） ℃ corresponding respectively to the acclimation temperatures 10 ℃, 15 ℃, 20 ℃, 25 ℃ and 15.76-5.42 ℃. The acclimation temperatures significantly influence on the preferred temperature, the high avoidance temperature and the high lethal temperature （P 〈 0.001）. The acclimation temperatures impose less influence on the preferred temperature than on the high avoidance temperature and high lethal temperature in tadpoles of this species. Any environmental factor, such as a diurnal pattern of temperature, that follows an approximately sinusoidal trajectory through time will exhibit a bi- or trimodal distribution. The optimality models modeled the bimodal environment as a mixture of two normal distributions sharing a common standard deviation and separated by an intermodal distance, and these models predicted that three fitness peaks would appear when the intermodal distance of the bimodally distributed temperature was 17 ℃. Results from this study fully supported the Optimality models.

关 键 词：驯化温度 最适温度 最高逃避温度 最高致死温度 大蟾蜍 蝌蚪 

分 类 号：Q958[生物学—动物学]