Ke Fushi, Li Jianyu, Vasseur Liette, You Minsheng, You Shijun
State Key Laboratory of Ecological Pest Control for Fujian-Taiwan Crops, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, China.
Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou, China.
Front Genet. 2022 Aug 30;13:986724. doi: 10.3389/fgene.2022.986724. eCollection 2022.
Genetic makeup of insect pest is informative for source-sink dynamics, spreading of insecticide resistant genes, and effective management. However, collecting samples from field populations without considering temporal resolution and calculating parameters related to historical gene flow may not capture contemporary genetic pattern and metapopulation dynamics of highly dispersive pests. (), the most widely distributed Lepidopteran pest that developed resistance to almost all current insecticides, migrates heterogeneously across space and time. To investigate its real-time genetic pattern and dynamics, we executed four samplings over two consecutive years across Southern China and Southeast Asia, and constructed population network based on contemporary gene flow. Across 48 populations, genetic structure analysis identified two differentiated insect swarms, of which the one with higher genetic variation was replaced by the other over time. We further inferred gene flow by estimation of kinship relationship and constructed migration network in each sampling time. Interestingly, we found mean migration distance at around 1,000 km. Such distance might have contributed to the formation of step-stone migration and migration circuit over large geographical scale. Probing network clustering across sampling times, we found a dynamic metapopulation with more active migration in spring than in winter, and identified a consistent pattern that some regions are sources (e.g., Yunnan in China, Myanmar and Vietnam) while several others are sinks (e.g., Guangdong and Fujian in China) over 2 years. Rapid turnover of insect swarms and highly dynamic metapopulation highlight the importance of temporal sampling and network analysis in investigation of source-sink relationships and thus effective pest management of , and other highly dispersive insect pests.
害虫的基因组成对于源 - 汇动态、抗杀虫剂基因的传播以及有效管理具有重要意义。然而，在不考虑时间分辨率的情况下从田间种群采集样本并计算与历史基因流相关的参数，可能无法捕捉到高扩散性害虫的当代遗传模式和集合种群动态。（）是分布最广的鳞翅目害虫，对几乎所有当前的杀虫剂都产生了抗性，其在空间和时间上的迁移具有不均匀性。为了研究其实时遗传模式和动态，我们在连续两年内对中国南方和东南亚进行了四次采样，并基于当代基因流构建了种群网络。在48个种群中，遗传结构分析识别出两个分化的虫群，其中遗传变异较高的虫群随时间被另一个所取代。我们通过估计亲缘关系进一步推断基因流，并在每个采样时间构建迁移网络。有趣的是，我们发现平均迁移距离约为1000公里。这样的距离可能有助于在大地理尺度上形成踏脚石式迁移和迁移回路。通过对各采样时间的网络聚类进行探究，我们发现了一个动态集合种群，春季的迁移比冬季更为活跃，并且在两年间确定了一种一致的模式，即一些地区是源（如中国云南、缅甸和越南），而其他一些地区是汇（如中国广东和福建）。虫群的快速更替和高度动态的集合种群凸显了时间采样和网络分析在研究源 - 汇关系以及从而对（该害虫）和其他高扩散性害虫进行有效害虫管理中的重要性。
