SUMMARY
The vegetative morphology and life history of Halopteris filicina (Grateloup) Kutzing, collected from Korea, were examined in laboratory culture. Field plants attaining 3–5 cm in height were epilithic, tufted, yellowish‐brown, and produced numerous erect axes with alternately distichous branches from compact basal discs. They were cultured under a 12:12 h LD photoperiod at 10°‐C, 15°C and 20°C to observe the influence of temperature on reproduction. At 10°C plants grew only vegetatively, whereas at 15°C and 20°C they produced unilocular sporangia. Unispores released from sporangia developed into monoecious, anisogamous gametophytes that formed plurilocular female and male gametangia on the same lateral branches. The zygotes, by fusion of female macrogametes and male microgametes, developed into sporophytes bearing unilocular sporangia, whereas the unfused female gametes germinated parthenogenetically. This species was confirmed to have an isomorphic life history, basically similar to the other species of Sphacelariales.
Growth and reproduction of Porphyra kuniedae from the southern coast of Korea were investigated. Biomass, plant size and occurrence of reproductive structures were monitored every other week from November 2001 to March 2002. Release of zygotospores and monospores from the plants was induced and the number of spores was counted in the laboratory culture every month. Biomass and plant size were found to be inversely correlated with water temperature. The maximum values in biomass and plant size were observed in mid-January with the lowest water temperature, and the values decreased with the increase of water temperature. Based on the cohort analysis, three cohorts started in late November, one to two cohorts were added every other week, and the maximum was eight in mid-January. The percentage of matured plants in the field was the highest in January. In the laboratory culture test, zygotospores were released more than monospores from large plants in late December while monospores were released much more than zygotospores since late January.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.