Abstract Detail

Molecular Ecology

Hu, Nan [1], Sanderson, Brian [2], Feng, Guanqiao [1], Guo, Minghao [3], Olson, Matt [4].

Different sex determination system in narrowleaf willow Salix exigua compared with other shrub willow species.

Dioecy is found in many plant lineages, but overall only ~6% of angiosperms have evolved dioecy. The Salicaceae family is unique in angiosperms because all species are dioecious. Studies of the genes controlling sex determination in this family have found that Populus trichocarpa has an XY sex determination system located on chromosome 19, whereas the closely related species Salix purpurea, S. suchowensis, and S. viminalis have a ZW system located on chromosome 15. We investigated the location of the sex determination system in Salix exigiua, which resides in a different section of the Salix phylogeny. To map the sex determination region (SDR), we randomly sequenced 24 males and 24 females from a natural population of Salix exigua. SDRs are characterized by increased genetic diversity (heterozygosity) and can be identified using Fst statistics comparing male and female genotypes. We called polymorphisms and calculated Fst using GATK and vcftools. Our results demonstrated that the sex chromosome of S. exigua is located on Chr15 and includes many of the same genes as S. purpurea, however heterozygosity evidence indicated that S. exigua has a XY system, which differs from S. purpurea. The speciation history of the Salicaceae family indicates that the SDR likely first shifted from Chr 19 to Chr 15, then shifted from XY to ZW. Accordingly, detailed comparisons between the XY SDR in S. exigua and the ZW SDR in S. purpurea will aid in understanding the mechanisms and dynamics causing the shift of sex determination system from XY to ZW.

1 - Texas Tech University, Biological Sciences, 2500 Broadway, Lubbock, TX 79409, Lubbock, Texas, 79409, USA
2 - Purdue University, 915 West State Street, West Lafayette, IN, 47907, United States
3 - Texas Tech University, Biological Sciences , 2500 Broadway, LUBBOCK, TX, 79409, United States
4 - Texas Tech University, Biological Sciences, Lubbock, TX, 79409, USA

Keywords:
sex determination
willow
sex evolution
narrowleaf willow.

Presentation Type: Poster
Session: P, Molecular Ecology Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PME003
Abstract ID:851
Candidate for Awards:None