Nielsen Anne L, Chen Shi, Fleischer Shelby J
Department of Entomology, Rutgers University Bridgeton, NJ, USA.
Department of Population Health and Pathobiology, North Carolina State University Raleigh, NC, USA.
Front Physiol. 2016 May 18;7:165. doi: 10.3389/fphys.2016.00165. eCollection 2016.
We developed an agent-based stochastic model expressing stage-specific phenology and population dynamics for an insect species across geographic regions. We used the invasive pentatomid, Halyomorpha halys, as the model organism because gaps in knowledge exist regarding its developmental physiology, it is expanding its global distribution, and it is of significant economic importance. Model predictions were compared against field observations over 3 years, and the parameter set that enables the largest population growth was applied to eight locations over 10 years, capturing the variation in temperature and photoperiod profiles of significant horticultural crop production that could be affected by H. halys in the US. As a species that overwinters as adults, critical photoperiod significantly impacted H. halys seasonality and population size through its influence on diapause termination and induction, and this may impact other insects with similar life-histories. Photoperiod and temperature interactions influenced life stage synchrony among years, resulting in an order of magnitude difference, for occurrence of key life stages. At all locations, there was a high degree of overlap among life stages and generation. Although all populations produced F2 adults and thus could be characterized as bivoltine, the size and relative contribution of each generation to the total, or overwintering, adult population also varied dramatically. In about half of the years in two locations (Geneva, NY and Salem, OR), F1 adults comprised half or more of the adult population at the end of the year. Yearly degree-day accumulation was a significant covariate influencing variation in population growth, and average maximum adult population size varied by 10-fold among locations. Average final population growth was positive (Asheville, NC, Homestead, FL, Davis, CA) or marginal (Geneva, NY, Bridgeton, NJ, Salem, OR, Riverside, CA), but was negative in one location (Wenatchee WA) due to cooler temperatures coupled with timing of vitellogenesis of F2 adults. Years of the highest population growth in the mid-Atlantic site coincided with years of highest crop damage reports. We discuss these results with respect to assumptions and critical knowledge gaps, the ability to realistically model phenology of species with strongly overlapping life stage and which diapause as adults.
我们开发了一种基于主体的随机模型，用于表达一种昆虫在不同地理区域的特定阶段物候和种群动态。我们使用入侵性蝽象——褐飞蝽作为模型生物，因为在其发育生理学方面存在知识空白，它正在扩大其全球分布，并且具有重大的经济重要性。将模型预测结果与3年的实地观测数据进行比较，并将能够实现最大种群增长的参数集应用于10年中的8个地点，捕捉了美国可能受到褐飞蝽影响的重要园艺作物生产中温度和光周期概况的变化。作为一种以成虫越冬的物种，临界光周期通过对滞育终止和诱导的影响，显著影响了褐飞蝽的季节性和种群规模，这可能会影响其他具有相似生活史的昆虫。光周期和温度的相互作用影响了不同年份之间的生活阶段同步性，导致关键生活阶段出现的数量级差异。在所有地点，生活阶段和世代之间都有高度的重叠。虽然所有种群都产生了F2代成虫，因此可以被描述为双季型，但每一代在总成虫种群或越冬成虫种群中的大小和相对贡献也有很大差异。在两个地点（纽约州日内瓦和俄勒冈州塞勒姆）大约一半年份中，F1代成虫在年末占成虫种群的一半或更多。年度度日积累是影响种群增长变化的一个重要协变量，不同地点的平均最大成虫种群规模相差10倍。平均最终种群增长在一些地点为正（北卡罗来纳州阿什维尔、佛罗里达州霍姆斯特德、加利福尼亚州戴维斯）或处于边缘状态（纽约州日内瓦、新泽西州布里奇顿、俄勒冈州塞勒姆、加利福尼亚州里弗赛德），但在一个地点（华盛顿州韦纳奇）为负，原因是温度较低以及F2代成虫卵黄发生的时间。大西洋中部地区种群增长最高的年份与作物受损报告最多的年份一致。我们根据假设和关键知识空白、对具有强烈重叠生活阶段且以成虫滞育的物种进行物候现实建模的能力来讨论这些结果。
