| Title: | "Parthenogenetic female populations in the brown alga Scytosiphon lomentaria (Scytosiphonaceae, Ectocarpales): decay of a sexual trait and acquisition of asexual traits" |
| Author(s): | Hoshino M; Okino T; Kogame K; |
| Address: | "Department of Natural History Sciences, Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan. Faculty of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810, Japan. Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan" |
| ISSN/ISBN: | 1529-8817 (Electronic) 0022-3646 (Linking) |
| Abstract: | "In isogamous brown algae, the sexuality of populations needs to be tested by laboratory crossing experiments, as the sexes of gametophytes are morphologically indistinguishable. In some cases, gamete fusion is not observed and the precise reproductive mode of the populations is unknown. In the isogamous brown alga Scytosiphon lomentaria in Japan, both asexual (gamete fusion is unobservable) and sexual populations (gamete fusion is observable) have been reported. In order to elucidate the reproductive mode of asexual populations in this species, we used PCR-based sex markers to investigate the sex ratio of three asexual and two sexual field populations. The markers indicated that the asexual populations consisted only of female individuals, whereas sexual populations are composed of both males and females. In culture, female gametes of most strains from asexual populations were able to fuse with male gametes; however, they had little to no detectable sexual pheromones, significantly larger cell sizes, and more rapid parthenogenetic development compared to female/male gametes from sexual populations. Investigations of sporophytic stages in the field indicated that alternation of gametophytic and parthenosporophytic stages occur in an asexual population. These results indicate that the S. lomentaria asexual populations are female populations that lack sexual reproduction and reproduce parthenogenetically. It is likely that females in the asexual populations have reduced a sexual trait (pheromone production) and have acquired asexual traits (larger gamete sizes and rapid parthenogenetic development)" |
| Keywords: | Female Japan Male *Parthenogenesis *Phaeophyta Phenotype Reproduction asexual population female-dominant population parthenogenesis reproductive mode sex marker sex ratio; |
| Notes: | "MedlineHoshino, Masakazu Okino, Tatsufumi Kogame, Kazuhiro eng MIKIMOTO FUND FOR MARINE ECOLOGY/International Research Support, Non-U.S. Gov't 2018/11/10 J Phycol. 2019 Feb; 55(1):204-213. doi: 10.1111/jpy.12812. Epub 2018 Dec 6" |
