Population genetics, species boundaries, and conservation in the Magnolia pacifica species complex along a continentality and moisture gradient in western Mexico

• DOI: 10.17129/botsci.2551
• Publication Date: 2020-08-14T06:01:46Z
• Authors: Miguel Ángel Muñi...; Luz Patricia Cast...; Ahtziri Socorro C...; José Antonio Vázq...; Anne Santerre
• Keywords: UPGMA; Isolation by distance; Lineage (genetic); Population Genetics

Background: In western Mexico, the Magnolia pacifica complex includes three morphologically defined, endemic and, endangered species, distributed along a 215 km continentality and moisture gradient: pugana, M. s.s. , vallartensis. 
 Hypothesis: Genetic evidence supports taxonomical classification of complex.
 Study site dates: Western samples were collected in 2012-2015.
 Methods: Six Inter-Simple Sequence Repeats (ISSR) primers amplified 76 clear reproducible fragments 278 individuals from 10 localities representative complex. ISSR dataset was analyzed using STRUCTURE 2.3.4, UPGMA clustering, Barrier 2.2, AMOVA. diversity parameters also estimated.
 Results: analyses revealed two main groups: pugana s.s.– vallartensis . Two subpopulations within each group evidenced, particularly separated Geographical barriers to gene flow identified. AMOVA similar significant proportion variation between groups. has lower genetic higher differentiation than s.s - group.
 Conclusions: Our results support recognition as genetically distinct lineage but did not reveal species boundary last taxa. distance isolation might explain structure pattern All groups subgroups defined this study should be considered separate conservation units, concerted efforts are needed protect them.