Department of Entomology, Faculty of Science, Cairo University, Giza 12613, Egypt.
Department of Biology, College of Science and Arts, Najran University, Najran 1988, Saudi Arabia.
J Insect Sci. 2024 Mar 1;24(2). doi: 10.1093/jisesa/ieae026.
Pollutants in an environment can have long-term implications for the species living there, resulting in local adaptations with implications for their genetic structure. Heavy metal pollutants infiltrate soils and groundwater, bioaccumulate in food webs, and negatively impact biota. In this study, we investigated the degree to which the genetic structure and variability of the slender green-winged grasshopper (Aiolopus thalassinus (Fabricius) (Orthoptera: Acrididae)) were impacted by heavy metal pollution and distance. We used the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) method to examine the genetic variability of populations in 3 heavy metal-polluted and 3 unpolluted locations across varying geographical distances in Egypt. The heavy metal concentrations of cadmium, copper, lead, and zinc were measured from the grasshopper tissue and soils. Sixty-nine unique and polymorphic bands were produced by 4 primers. Cluster and principal component analyses separated the populations inside and outside Cairo into 2 main branches, which were further divided into smaller branches corresponding to their geographical regions. We found no differences in the Shannon genetic diversity index between populations or with increasing heavy metal concentrations in either the soil or the grasshopper tissue. Our results showed a greater genetic variation among populations than between populations within the same location, indicating populations within locations were less differentiated than those between locations. The moderate correlation between genetic similarity and spatial distance suggests geographical isolation influenced grasshopper population differentiation. Based on the RAPD analysis, environmental pollutants and geographical distances impact the A. thalassinus population structure, potentially restricting gene flow between sites even at small spatial scales.
环境中的污染物会对当地的物种产生长期影响，导致它们产生局部适应性，从而影响其遗传结构。重金属污染物会渗透到土壤和地下水中，在食物网中生物累积，并对生物区系产生负面影响。在这项研究中，我们调查了重金属污染和距离对细长绿蚱蜢（Aiolopus thalassinus（Fabricius）（直翅目：蝗科））遗传结构和变异性的影响程度。我们使用随机扩增多态性 DNA-聚合酶链反应（RAPD-PCR）方法，研究了分布在埃及不同地理位置的 3 个重金属污染和 3 个无污染地区的种群的遗传变异性。从蚱蜢组织和土壤中测量了镉、铜、铅和锌的重金属浓度。4 个引物产生了 69 个独特的多态性条带。聚类和主成分分析将开罗内外的种群分为 2 个主要分支，进一步分为与地理区域相对应的较小分支。我们没有发现种群之间或土壤或蚱蜢组织中重金属浓度增加与 Shannon 遗传多样性指数之间的差异。我们的结果表明，种群之间的遗传变异性大于同一地点内的种群之间的遗传变异性，表明地点内的种群比地点间的种群分化程度更低。遗传相似性与空间距离之间的中度相关性表明地理隔离影响了蚱蜢种群的分化。基于 RAPD 分析，环境污染物和地理距离影响 A. thalassinus 种群结构，即使在小的空间尺度上也可能限制基因流。
