Uniparentality: advantages for range expansion in diploid and diploid- autopolyploid species

REUTEMANN A.VERENA; MARTINEZ E.J.; SCHEDLER, MARA; DAVIÑA JULIO R.; HOJSGAARD, DIEGO; HONFI ANA I.

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2022 vol. 2022 p. 1 - 23

0024-4074

Uniparental reproduction, i.e. an individual’s capacity to produce offspring autonomously, is expected to facilitate range expansion of populations. Paspalum species reproduce uniparentally by sexual (self-fertility) and asexual (apomixis) reproduction, and biparentally by sexual (self-sterility) reproduction. We evaluated the relationship between contrasting reproductive strategies (uni- and biparentality) and their impact on the colonizing ability and geographical range sizes of populations. We determined the cytotype composition of sixteen populations from Paspalum indecorum, P. cromyorhizon, P. pumilum, and P. maculosum, and assessed the sexual (self-fertile and self-sterile) and apomictic proportions by cyto-embryological analyses, fertility rates and seed flow cytometry. Data obtained regarding reproductive modes were compared to the distribution range of each cytotype and species. Sexual diploids with moderate degrees of self-fertility and mixed pollination syndromes showed wider distribution ranges compared to self-sterile diploids. In sexual diploids, increased rates of self-fertility relate to larger distribution areas, and in agamic complexes, self-fertility reduces the differences in range sizes between biparental diploids and uniparental tetraploids. In such complexes, the range size of diploid cytotypes explains the range size and dispersal of apomictic tetraploids. Thus, uniparental reproduction via self-fertility and apomixis describes patterns of geographical parthenogenesis in South American species.