Data from: Symbiont infection and psyllid haplotype influence phenotypic plasticity during host switching events

Many herbivorous insect species exhibit phenotypic plasticity when using multiple hosts, which facilitates survival in heterogeneous host environments. Physiological host acclimation is an important part of it, yet the effects of host acclimation on insect feeding behavior are not well studied, particularly for insect vectors of plant pathogens. We studied the combined effects of host acclimation and infection with a plant pathogenic symbiont on feeding behavior of Bactericera cockerelli, an oligophagous psyllid widespread in both crop and natural habitats that feeds primarily on Solanaceae and transmits an economically important plant pathogen, Candidatus Liberibacter solanacearum (CLso). We used a factorial design and the electrical penetration graphing technique to disentangle the effects of host acclimation, CLso infection, and psyllid haplotype on the within-plant feeding behavior of B. cockerelli during conspecific and heterospecific host switches. This approach allows to connect phenotypic plasticity with the role of B. cockerelli as a vector by quantifying the frequency and duration of behaviors involved in CLso transmission. We found significant reductions in multiple metrics of B. cockerelli feeding efficiency, exacerbated by infection with CLso, which could lead to reduced transmission of this pathogen. Psyllid genotype was also important; the Central haplotype exhibited less dramatic changes in feeding efficiency than the Western haplotype during heterospecific host switches. Our study shows that host acclimation and heterospecific host switching directly alter feeding behaviors underlying pathogen transmission, and that the magnitude of feeding efficiency reductions depends on both host genotype and infection status.诸多植食性昆虫物种在利用多种寄主植物时会表现出表型可塑性（phenotypic plasticity），该特性可帮助其在异质化的寄主环境中存活。寄主生理适应（host acclimation）是这一过程的重要组成部分，但目前关于寄主适应对昆虫取食行为的影响尚未得到充分研究，针对植物病原昆虫介体的相关探究尤为匮乏。本研究针对寄主适应与植物病原共生菌感染对番茄斑翅木虱（Bactericera cockerelli）取食行为的联合影响展开系统探究，该木虱为寡食性物种，广泛分布于农田与自然生境中，主要取食茄科植物，并可传播一种具有重大经济影响的植物病原——候选种Candidatus Liberibacter solanacearum（CLso）。本研究采用析因设计与电刺探电位图谱（electrical penetration graphing, EPG）技术，解析了寄主适应、CLso感染以及木虱单倍型对番茄斑翅木虱在同种与异种寄主转换过程中植株内取食行为的调控作用，该方法可通过量化与CLso传播相关的取食行为的发生频率与持续时长，将表型可塑性与番茄斑翅木虱作为介体的功能关联起来。研究结果显示，番茄斑翅木虱取食效率的多项指标均出现显著下降，而CLso感染会进一步加剧这一效应，这可能会降低该病原菌的传播效率。木虱的基因型同样发挥关键作用，在异种寄主转换过程中，中部分支单倍型的取食效率变化幅度显著小于西部单倍型。本研究表明，寄主适应与异种寄主转换可直接改变与病原菌传播相关的取食行为，且取食效率下降的幅度同时取决于寄主基因型与感染状态。