Karyology and effects of temperature and photoperiod on the life-history of Bangia atropurpurea C Ag from the Mediterranean Sea
Gargiulo, G.M.; Culoso, F.; Genovese, G.; De Masi, F.
Cryptogamie Algologie 17(1): 45-55
The effects of temperature, photoperiod and karyology of Bangia atropurpurea (Roth) C. Ag. from the Strait of Messina were studied in the field and laboratory. Conchospores were formed and released in short day conditions and at temperature of 15-18 degree C, with the maximum of production and release at 18 degree C. Culture data correlate well with field observations on seasonal periodicity of growth and reproduction. Germination and development of monospores and conchospores were not influenced by photoperiod or by light intensity. Temperatures above 25 degree C were lethal for the all types of spores and gametophytic thalli. The life history in culture corresponds to a typical sexual biphasic cycle with the gametophytic phase showing n = 3 chromosomes and the "Conchocelis" one n = 6. Monospores were produced only by gametophytic plants.