Abstract:
Phenological models for insect pests often rely on knowledge of thermal reaction norms. These may differ in shape depending on developmental thermal conditions (e.g. constant vs. fluctuating) and other factors such as life-stages. Here, we conducted an extensive comparative study of the thermal reaction norms for development and viability in the invasive fly, Drosophila suzukii, under constant and fluctuating thermal regimes. Flies, were submitted to 15 different constant temperatures (CT) ranging from 8 to 35 °C. We compared responses under CT with patterns observed under 15 different fluctuating temperature (FT) regimes. We tested several equations for thermal performance curves and compared various models to obtain thermal limits and degree-day estimations. To validate the model\'s predictions, the phenology was monitored in two artificial field-like conditions and two natural conditions in outdoor cages during spring and winter. Thermal reaction norm for viability from egg to pupa was broader than that from egg to adult. FT conditions yielded a broader thermal breadth for viability than CT, with a performance extended towards the colder side, consistent with our field observations in winter. Models resulting from both CT and FT conditions made accurate predictions of degree-day as long as the temperature remained within the linear part of the developmental rate curve. Under cold artificial and natural winter conditions, a model based on FT data made more accurate predictions. Model based on CT failed to predict adult\'s emergence in winter. We also document the first record of development and adult emergence throughout winter in D. suzukii. Population dynamics models in D. suzukii are all based on summer phenotype and CT. Accounting for variations between seasonal phenotypes, stages, and thermal conditions (CT vs. FT) could improve the predictive power of the models.
摘要:
害虫的物候模型通常依赖于热反应规范的知识。这些可能在形状上有所不同,具体取决于发育热条件(例如,常数与波动)和其他因素,如生命阶段。这里,我们对侵入性苍蝇的发育和生存能力的热反应规范进行了广泛的比较研究,果蝇,在恒定和波动的热态下。苍蝇,接受15种不同的恒定温度(CT),范围从8到35°C。我们将CT下的响应与15种不同波动温度(FT)方案下观察到的模式进行了比较。我们测试了几个方程的热性能曲线,并比较了各种模型,以获得热极限和度日估计。要验证模型的预测,在春季和冬季,在两种人工野外条件和两种自然条件下在室外笼子中监测物候。从鸡蛋到p的生存力的热反应规范比从鸡蛋到成虫的要宽。FT条件比CT产生了更宽的生存力热宽度,随着表演向更冷的一侧延伸,与我们在冬季的实地观察一致。只要温度保持在发育速率曲线的线性部分内,由CT和FT条件产生的模型就可以准确预测度日。在寒冷的人工和自然冬季条件下,基于FT数据的模型做出了更准确的预测。基于CT的模型无法预测冬季成人的出现。我们还记录了D.suzuki整个冬季的发育和成年出现的第一个记录。suzukii的种群动态模型均基于夏季表型和CT。考虑季节性表型之间的差异,阶段,和热条件(CT与FT)可以提高模型的预测能力。