Seasonal growth, density, reproductive phenology and agar quality of Gracilaria sordida (Gracilariales, Rhodophyta) at Mokomoko Inlet, New Zealand

Abstract

Growth of mesh-enclosed Gracilaria sordida plants was determined monthly for one year at the Mokomoko mudflat, South Island, New Zealand . Growth of plants with permanent water cover was correlated with water temperature and was most rapid during summer months . Plants exposed at low tide grew only during early spring and late autumn . Bimonthly quadrat sampling of a mudflat population showed that all stages of the life cycle were present throughout the year . Spermatangial plant length and biomass were greatest in early spring ; cystocarpic and tetrasporic plants were greatest in midsummer . Sterile plants were most numerous in the late summer . Agar yield showed little variation either seasonally or between different stages of the life cycle . Agar gel strengths for all life cycle stages were greatest at the time of peak plant size and abundance . Gels from spermatangial plants generally were weaker than those from other stages .

Genome-wide identification of the GT7 and GH16 genes and their correlations with agar metabolism in the agarophyte Gracilariopsis lemaneiformis

“…Nitrogen can influence agar yield (Chen Q. L. et al, 2022). The agar contents of Gracilaria sordida was shown to be negatively correlated with the nitrogen level of the environment (Pickering et al, 1990). In our study, the agar content of Gp.…”