Cross-fertilization and hybrid development of forms of the brown alga Hormosira banksii (Turner) Decaisne

Abstract

Gametes from four forms of Hormosira banksii(f. banksii, f. gracilis, f, sieberi and f.pumila) from the coast at Victor Harbor and Aldinga, in South Australia, cross-fertilize readily in all combinations and the zygotes develop into healthy germlings. Nearly all developed to the first vesicle stage and a few were successfully cultured to plants 24 cm high with many vesicles. The larger plants had immature but typical conceptacles but did not become fertile before loss at 15 months. The above taxa are considered to be at subspecific levels.