Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.
Natural Resources Canada-Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, Canada.
PLoS One. 2022 Jun 10;17(6):e0269373. doi: 10.1371/journal.pone.0269373. eCollection 2022.
The South African macadamia industry is severely affected by a complex of stink bugs, dominated by the two-spotted stink bug, Bathycoelia distincta Distant (Pentatomidae). This species was first discovered during the spring of 1984 in the Limpopo province. Although considerable effort has been spent trying to manage this pest, it continues to be a pest of concern for the macadamia industry. Information on the genetic diversity of this species is lacking, despite the potential relevance of such information for management strategies. The present study aimed to characterise the genetic diversity of B. distincta populations in South Africa. The Cytochrome c Oxidase Subunit 1 (COI) and cytochrome b (Cytb) gene regions were sequenced from individuals collected from the three main regions of macadamia production over three different seasons (2018-2020). An overall high haplotype diversity (COI = 0.744, Cytb = 0.549 and COI+Cytb = 0.875) was observed. Pairwise mean genetic distance between populations from each region varied from 0.2-0.4% in both datasets, which suggests the absence of cryptic species. The median joining network for both datasets consisted of one or two central haplotypes shared between the regions in addition to unique haplotypes observed in each region. Finally, low genetic differentiation (FST < 0.1), high gene flow (Nm > 1) and the absence of a correlation between genetic and geographic distance were estimated among populations. Overall, these results suggest that the B. distincta populations are not structured among the areas of macadamia production in South Africa. This might be due to its ability to feed and reproduce on various plants and its high dispersal (airborne) between the different growing regions of the country along with the rapid expansion of macadamia plantations in South Africa.
南非澳洲坚果产业受到一系列臭虫的严重影响，其中以两点臭虫 Bathycoelia distincta Distant（半翅目）为主。该物种于 1984 年春季首次在林波波省发现。尽管已经投入了相当大的努力来管理这种害虫，但它仍然是澳洲坚果产业关注的害虫。尽管此类信息对于管理策略具有潜在的相关性，但该物种的遗传多样性信息却缺乏。本研究旨在描述南非 B. distincta 种群的遗传多样性。从三个主要的澳洲坚果生产地区在三个不同季节（2018-2020 年）收集的个体中，对细胞色素 c 氧化酶亚单位 1（COI）和细胞色素 b（Cytb）基因区域进行了测序。观察到总体高单倍型多样性（COI = 0.744，Cytb = 0.549 和 COI+Cytb = 0.875）。来自每个地区的种群之间的成对平均遗传距离在两个数据集之间均为 0.2-0.4％，这表明不存在隐种。两个数据集的中位数连接网络都由一个或两个中心单倍型组成，这些单倍型在各个地区之间共享，此外还观察到每个地区特有的单倍型。最后，估计种群之间的遗传分化（FST <0.1）低，基因流（Nm >1）高，遗传距离与地理距离之间不存在相关性。总体而言，这些结果表明，B. distincta 种群在南非的澳洲坚果生产区之间没有结构。这可能是由于它能够在各种植物上进食和繁殖，并且能够在该国不同的种植区之间通过空气传播进行高分散性传播，以及南非的澳洲坚果种植园迅速扩张所致。
