Department of Horticulture Science, College of Agriculture and Natural Resource Science, Debreberhan University, Debreberhan, Ethiopia.
J Insect Sci. 2024 Mar 1;24(2). doi: 10.1093/jisesa/ieae017.
Inbreeding can have detrimental effects on reproductive fitness, but the extent of lineage-specific variation in these effects remains poorly understood. This study investigated the effects of brother and sister inbreeding on reproductive fitness in 2 lineages (L1 and T) of T. tabaci. Inbred females from both lineages exhibited a significant reduction in longevity compared with the control group. The L1 lineage experienced a 27% and 43% decrease in longevity in the F2 and F3 generations, respectively, while the T lineage showed a similar trend with a 30% and 44% decrease. The T lineage consistently displayed slightly longer lifespans than the L1 lineage across all generations. Brother and sister inbreeding also led to a decrease in fecundity rates in both lineages. In the F3 generation, the number of eggs laid decreased by 59% compared with the F2 generation. The T lineage consistently exhibited slightly lower fecundity rates compared with the L1 lineage. Egg hatchability rates declined with subsequent inbreeding, with the F3 generation showing lower rates compared with the F2 generation. However, the T lineage did not exhibit a significant difference in inbreeding depression for egg hatchability rates, while the L1 lineage demonstrated a noticeable decrease. Deformities observed in male L1 lineage resulting from inbreeding were consistent with disruptions in normal developmental processes, affecting various body parts such as legs, antennae, and wings. Continued inbreeding increased susceptibility to inbreeding depression in terms of longevity, fecundity, and egg hatchability.
近亲繁殖会对生殖适应性产生不利影响，但这些影响在谱系间的具体差异程度仍知之甚少。本研究调查了兄妹近亲繁殖对 2 个烟粉虱谱系（L1 和 T）生殖适应性的影响。与对照组相比，来自这两个谱系的近亲繁殖雌虫的寿命显著缩短。L1 谱系在 F2 和 F3 代中分别经历了 27%和 43%的寿命减少，而 T 谱系表现出类似的趋势，分别减少了 30%和 44%。在所有世代中，T 谱系的寿命始终略长于 L1 谱系。兄妹近亲繁殖也导致两个谱系的繁殖力下降。在 F3 代中，与 F2 代相比，产卵量减少了 59%。T 谱系的繁殖力始终略低于 L1 谱系。随着后续近亲繁殖，卵孵化率下降，F3 代的孵化率低于 F2 代。然而，T 谱系在卵孵化率的近亲繁殖衰退方面没有表现出显著差异，而 L1 谱系则表现出明显的下降。由于近亲繁殖，L1 谱系雄性出现的畸形与正常发育过程的中断一致，影响了腿部、触角和翅膀等各种身体部位。持续近亲繁殖增加了在寿命、繁殖力和卵孵化率方面对近亲繁殖衰退的易感性。
