昼夜温度波动对麦长管蚜生理生态表型影响及其相关性研究

Study on physiological and ecological phenotypes of the wheat aphid,Sitobion avenae (Fabricius) and its correlation under temperature amplitudes

昼夜温度波动变化是气候变暖的主要特征之一,昼夜变温幅度对生物的影响越来越受到科学家的关注。与恒温研究相比,变温幅度对昆虫生活史特征影响的研究还十分有限。因此,本研究模拟自然界24 h温度变化,并首次全面研究了相同平均温度(22℃)下不同变温幅度(±0℃、±6℃、±12℃)对麦长管蚜Sitobion avenae生理指标(温度耐受性、呼吸)与生态指标(发育、存活、寿命、繁殖、种群参数)的影响。结果表明,与变温幅度±0℃和±12℃相比,变温幅度±6℃显著提高了麦长管蚜整体存活、寿命、繁殖以及净增值率与世代周期。与其它处理相比,较大变温幅度±12℃显著阻碍了麦长管蚜若虫发育,抑制了整体存活,缩短了寿命,降低了繁殖量,且显著降低了种群内禀增长率、净增值率与世代周期。但是,较大变温幅度±12℃,显著提高了成蚜的耐热、耐寒性与CO_(2)呼吸速率。研究还发现,在不同变温幅度中,麦长管蚜成蚜耐寒性的提高是以寿命为代价的。由此可见,以往以恒温为基础的昆虫种群表型及数量动态预测模型均存在局限,昼夜变温幅度作为必要因素,应考虑纳入种群表型及数量动态预测模型中,从而提高昆虫田间发生情况预测预报的准确性与气候变化对生物的风险评估的精确性。

Diurnal temperature fluctuation is one of the main features of climate warming.Scientists pay more attention to the impact of temperature fluctuation on organisms.However,compared with the constant temperature,the effect of the temperature amplitude on insect life history is still limited.Therefore,we had simulated different temperature amplitudes(±0℃,±6℃,±12℃) with the same mean temperature(22℃) and had firstly studied the effect of temperature amplitudes on the physiological indexes(thermal tolerance,respiration) and ecological indexes(development,survival,life span,reproduction,population parameters) of the wheat aphid,Sitobion avenae(Fabricius).The results showed that,compared to temperature amplitudes ±0℃ and ±12℃,temperature amplitude ±6℃ significantly improved the survival,longevity,reproduction,net reproduction rate and generation time.Compared with other treatments,temperature amplitude ±12℃ significantly hindered the development of the nymphs,inhibited survival,shortened the longevity,reduced reproduction,and significantly reduced the intrinsic growth rate,net reproduction rate and generation time.However,the temperature amplitude ±12℃ significantly increased the heat and cold resistance and respiration rate.It was also found that the improvement of cold tolerance was at the cost of longevity in different temperature amplitudes in the adult.It could be seen that insect population dynamic prediction models in the previous based on the constant temperature have limitations.As a necessary factor,diurnal temperature fluctuation should be considered into the population dynamic prediction models to improve the accuracy of insect field prediction and the precision of biological risk assessment due to climate change.