Yoshimoto Andrew, Szűcs Marianna
Department of Entomology Michigan State University East Lansing Michigan USA.
Ecol Evol. 2024 Feb 8;14(2):e10936. doi: 10.1002/ece3.10936. eCollection 2024 Feb.
Intraspecific hybridization between distinct populations could increase the fitness and adaptive potential of biological control agents that often have low genetic diversity and can be inbred due to long-term laboratory rearing often at small population sizes. Hybridization can also alter host preference and performance when the parental insect populations are adapted to different host plants. We investigated the effects of hybridization between two populations (Northern and Southern) of the psyllid, , that have different fitness on three invasive knotweed species (Japanese, giant, and Bohemian). Fecundity, host choice, and developmental success of second-generation reciprocal hybrids and the parental psyllid populations were compared on the three knotweed species in multiple-choice tests. Hybridization did not increase fecundity. All three knotweed species were accepted for oviposition without preference by the Southern and the two hybrid psyllid populations. The northern psyllid population laid the most eggs on Bohemian knotweeds but those were maladaptive choices since almost all eggs failed to develop. The developmental success of the parental psyllid populations was highest on the knotweed species they were originally collected from, on Japanese knotweed of the Southern psyllids and giant knotweed of the Northern psyllids. Hybrids had intermediate or higher survival on given knotweed hosts compared to their parents. These results can inform release tactics of in different regions especially where there appear to be climatic and/or host mismatches such as in Michigan. In southern Michigan, based on climate the Northern psyllid population should be released. However, the most common knotweed species in the region are Bohemian and Japanese knotweeds that do not support the development of the Northern psyllids. In this case, hybrids that may carry cold adaptations of the Northern psyllids but have better developmental success on the prevailing knotweed species may be considered for release to increase establishment success.
不同种群之间的种内杂交可以提高生物防治剂的适应性和适应潜力，这些生物防治剂通常遗传多样性较低，并且由于长期在小种群规模下进行实验室饲养而可能近亲繁殖。当亲本昆虫种群适应不同的寄主植物时，杂交也会改变寄主偏好和表现。我们研究了两种木虱种群（北方种群和南方种群）之间杂交的影响，这两种种群对三种入侵蓼科植物（日本虎杖、巨型虎杖和波希米亚虎杖）具有不同的适应性。在多项选择试验中，比较了第二代正反交杂种和亲本木虱种群在这三种蓼科植物上的繁殖力、寄主选择和发育成功率。杂交并没有提高繁殖力。南方种群和两个杂交木虱种群对所有三种蓼科植物都无偏好地接受产卵。北方木虱种群在波希米亚虎杖上产卵最多，但这些都是不适应的选择，因为几乎所有的卵都未能发育。亲本木虱种群在它们最初采集的蓼科植物上发育成功率最高，南方木虱在日本虎杖上，北方木虱在巨型虎杖上。与亲本相比，杂种在特定的蓼科寄主上具有中等或更高的存活率。这些结果可以为不同地区的木虱释放策略提供参考，特别是在存在气候和/或寄主不匹配的地区，如密歇根州。在密歇根州南部，根据气候条件，应该释放北方木虱种群。然而，该地区最常见的蓼科植物是波希米亚虎杖和日本虎杖，它们不支持北方木虱的发育。在这种情况下，可以考虑释放可能携带北方木虱耐寒适应性但在当地主要蓼科植物上发育成功率更高的杂种，以提高定殖成功率。
