Pós-Graduação em Genética - Faculdade de Medicina de Ribeirão Preto, Univ de São Paulo, Ribeirão Preto, Brazil.
Depto de Ciências Biológicas - DEBIO, Univ Estadual do Centro-Oeste - UNICENTRO, Paraná, Brazil.
Neotrop Entomol. 2021 Aug;50(4):515-523. doi: 10.1007/s13744-021-00866-2. Epub 2021 Apr 12.
The insect/plant interaction is known to be a trigger for diversification and even speciation. Experimental analyses on fitness traits and phenotypic variation using alternative host sites have been performed to understand the process of diversification relative to insect/plant interactions. For cactophilic species of Drosophila, the speciation process is considered an adaptive radiation in response to the exploration of species of the Cactaceae as breeding and feeding sites. In this work, we analyzed life history and morphological traits in individuals from two phyletic lineages (Evolutionarily Significant Units ESU) of the cactophilic species Drosophila meridionalis (Wasserman 1962) (Diptera: Drosophilidae) raised from media prepare. The characters analyzed corresponded to viability, developmental time, and four morphological measurements. The experiments were performed in a semi-natural medium prepared with fermenting tissues of the natural hosts, Cereus hildmaniannus and Opuntia monacantha. Viability, development time, and three morphological measurements were influenced by lineage, suggesting differentiation between the lineages. However, in O. monacantha, the mean viability was greater (15%) and development time was longer (336 h) than in C. hildmaniannus (~11% and ~301 h, respectively). Only the developmental time was significantly affected by the host cactus. In general, ESU group A had better values than ESU group BC for the evaluated traits. This finding suggested differentiation between the two lineages and different plastic responsiveness to the contrasting environments of the hosts, and that C. hildmaniannus may be a relatively stressful environment for the larvae, as for other Drosophila species.
昆虫/植物的相互作用是多样化甚至物种形成的已知触发因素。已经使用替代宿主位点进行了对适合度特征和表型变异的实验分析，以了解相对于昆虫/植物相互作用的多样化过程。对于嗜仙人掌的果蝇物种，物种形成过程被认为是对仙人掌科物种作为繁殖和觅食场所的探索的适应性辐射。在这项工作中，我们分析了从嗜仙人掌的果蝇物种 Drosophila meridionalis（Wasserman 1962）（双翅目：果蝇科）的两个系统发育谱系（进化上有意义的单位 ESU）个体的生活史和形态特征，这些个体是从准备好的培养基中培养出来的。分析的特征对应于存活率、发育时间和四个形态测量值。实验是在半自然培养基中进行的，该培养基是用天然宿主的发酵组织制备的，包括 Cereus hildmaniannus 和 Opuntia monacantha。存活率、发育时间和三个形态测量值受到谱系的影响，表明谱系之间存在分化。然而，在 O. monacantha 中，平均存活率更高（约 15%），发育时间更长（约 336 小时），而在 C. hildmaniannus 中，分别为（约 11%和约 301 小时）。只有发育时间受到宿主仙人掌的显著影响。一般来说，与 ESU 组 BC 相比，ESU 组 A 对评估性状具有更好的值。这一发现表明，两个谱系之间存在分化，并且对宿主环境的不同可塑性反应不同，并且 C. hildmaniannus 可能对幼虫来说是一个相对有压力的环境，就像对其他果蝇物种一样。
