Zettler J A, Adams K, Frederick B, Gutting A, Ingebretsen N, Ragsdale A, Schrey A
Department of Biology, Armstrong State University, Savannah, GA 31419, USA.
J Genet. 2017 Mar;96(1):33-38. doi: 10.1007/s12041-016-0736-9.
In 2012, the orchid mealy bug Pseudococcus microcirculus was first detected in situ in North America's more diverse orchid region, the Big Cypress Basin (Collier Co FL). A follow-up survey showed that the mealy bug is more widespread and found on epiphytic orchids in two locations, in both the Fakahatchee Strand State Preserve (sites B and F) and the Florida Panther National Wildlife Refuge (sites M and C). There, we collected mealy bugs (n = 54) from 35 orchid individuals and screened allelic variation at seven microsatellite loci. We estimated genetic diversity and differentiation among all sites and compared the variation among individuals collected on the same plant. Genetic differentiation between sites M and C (F = 0.03, P < 0.01) and,Mand B (F = 0.04, P < 0.01) was detected.We also detected significantly lower mean pairwise relatedness among individuals from site B compared to all the other locations, and this population had the lowest inbreeding coefficient. Genetic diversity and mean pairwise relatedness were highly variable among plants with multiple individuals; however, plants from sites F and M tend to have collections of individuals with higher mean pairwise relatedness compared to sites B and C. Our results indicate that there is genetic diversity and differentiation among mealy bugs in these locations, and that collections of individuals on the same plant are genetically diverse. As such, the mealy bugs throughout these areas are likely to be genetically diverse and exist in multiple distinct populations.
2012年，在北美生物多样性更高的兰花产区——大柏树盆地（佛罗里达州科利尔县）首次发现了兰花粉蚧微小伪球菌的自然种群。后续调查显示，这种粉蚧分布更为广泛，在法卡哈奇斯特兰德州立保护区（B点和F点）以及佛罗里达美洲豹国家野生动物保护区（M点和C点）的两个地点的附生兰花上均有发现。在那里，我们从35株兰花个体上采集了粉蚧（n = 54），并筛选了7个微卫星位点的等位基因变异。我们估计了所有地点之间的遗传多样性和分化情况，并比较了在同一植株上采集的个体之间的变异。检测到M点和C点之间（F = 0.03，P < 0.01）以及M点和B点之间（F = 0.04，P < 0.01）存在遗传分化。我们还检测到，与所有其他地点相比，B点个体之间的平均成对亲缘关系显著更低，且该种群的近亲繁殖系数最低。在有多株个体的植株中，遗传多样性和平均成对亲缘关系差异很大；然而，与B点和C点相比，F点和M点植株上采集的个体往往具有更高的平均成对亲缘关系。我们的结果表明，这些地点的粉蚧之间存在遗传多样性和分化，并且同一植株上采集的个体在基因上是多样的。因此，这些区域的粉蚧可能在基因上具有多样性，并且存在多个不同的种群。
