Abstract Detail

Ericaceae: Systematics, Ecology and Evolution

Braukmann, Thomas [1], Stefanovic, Sasa [2].

Repeats, rearrangements, and reductions: the architecture of Ericaceae plastomes.

Mycoheterotrophic (MHT) plants exhibit a wide range of evolutionary degradation of photosynthetic ability and rely entirely or partially on their photosynthetic hosts to supply water and nutrients via fungal intermediaries. There are at least 10 independent origins of MHT among land plants. The transition from autotrophy to heterotrophy is associated with changes to the plastid genome (plastome) with respect to its size, gene content, and structure. The heather family (Ericaceae) is a large family containing autotrophs as well as fully and partially MHT plants. We sequenced the plastomes of four autotrophic and three mixotrophic species and included publically available plastomes in the analysis. Our results indicate that the rearrangements of the large single copy region are commonplace for Ericaceae. Associated with these extensive structural rearrangements of the plastome within the family, including fully MHT species, is an increase in forward and palindromic repeats. Additionally, most Ericaceae share the loss of the plastid ycf1, ycf2, and clpP genes, which is rare even amongst fully heterotrophic plant lineages. Mixotrophic plants retain most genes relating to photosynthesis but are variable for the plastid ndh genes. We found that the plastomes of Ericaceae species are generally under strong purifying selection but found positive selection acting on the branch leading to subfamilies Vaccinoideae and Ericoideae for the rps, rpl, and rpo genes.

1 - University of Guelph, Biodiversity Institute of Ontario, Guelph, ON, Canada
2 - University Of Toronto Mississauga, Department Of Biology, 3359 Mississauga Rd, Mississauga, ON, L5L 1C6, Canada

Keywords:
Ericaceae
mycoheterotrophic plants
plastome.

Presentation Type: Colloquium Presentations
Session: C07b, Ericaceae: Systematics, Ecology, and Evolution Part 2
Location: 114/Mayo Civic Center
Date: Tuesday, July 24th, 2018
Time: 1:30 PM
Number: C07b001
Abstract ID:391
Candidate for Awards:None