Abstract Detail



Physiology

Lewis, Raymond [1].

The effects of salinity on the development of microscopic life history stages of the marine brown alga Alaria marginata.

A variety of factors affect the reproductive development of microscopic gametophytes of the large brown algae known as kelps. Reducing the salinity of the seawater has been observed to increase gametogenesis in some species. This study explores the effects of a range of salinities on several developmental processes of spores of the winged kelp, Alaria marginata, as the spores germinate to form gametophytes. Sporophytes were collected at Granite Canyon, Monterey Co., California. Spores were induced to release and were cultured at a constant density in nutrient enriched seawater ranging from 15 to 33 SA, made by adding distilled water to 33 SA seawater. Germination rate was highest at 24-33 SA. Oogenesis and sporophyte production on a per gametophyte basis were highest from 21-30 SA with very few eggs and sporophytes produced at 15 SA.  Sporophyte production per unit area was slightly higher at 30 SA, reflecting the accumulation of slight differences in germination and oogenesis. In contrast, sporophyte growth increased with increasing salinity with the highest growth at 33 SA. Thus, it appears that the gametophyte and sporophyte generations have very different responses to salinity. The optimal salinity for sporophyte growth was not determined, but since the seawater was at 33 SA, it is possible that this is the optimal salinity for sporophyte growth.


1 - Wheaton College, Department of Biology, 501 College Ave, Wheaton, IL, 60187, US

Keywords:
algae
salinity
reproductive biology
Ecophysiology.

Presentation Type: Oral Paper
Session: PHYS2, Physiology II
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 4:15 PM
Number: PHYS2006
Abstract ID:735
Candidate for Awards:None


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