Unprecedented Parallel Photosynthetic Losses in a Heterotrophic Orchid Genus.

ABSTRACT: Heterotrophic plants are evolutionary experiments in genomic, morphological, and physiological change. Yet, genomic sampling gaps exist among independently derived heterotrophic lineages, leaving unanswered questions about the process of genome modification. Here, we have sequenced complete plastid genomes for all species of the leafless orchid genus Hexalectris, including multiple individuals for most, and leafy relatives Basiphyllaea and Bletia. Our objectives are to determine the number of independent losses of photosynthesis and to test hypotheses on the process of genome degradation as a result of relaxed selection. We demonstrate four to five independent losses of photosynthesis in Hexalectris based on degradation of the photosynthetic apparatus, with all but two species displaying e

SUBMITTER: Barrett CF 

PROVIDER: S-EPMC6736286 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature