NEW SPECIES AND NEW COMBINATION OF THE GENUS BREMIELLA ON COMPOSITAE OF CHINA

The genus Bremiella of Peronosporaceae was erected by Wilson in 1914, based upon a fungus described by Berlese as Peronospora megasperma. Two species of this genus were hitherto known from the world. In this paper, one new species and two new combinations parasitic on Compositae are reported. The new species is Bremiella multifermis sp. nov. on Chrysanthemum coronarium var. spatiosum Bailey. Two new combinations are: B. chaysanthemi-coronarii (Sawada) comb. nov. on Chrysanthemum coronarium L. and B. artemisiae-annuae (Ling et M. C. Tai) comb. nov. on Artemisia annua L. Bremiella multiformis sp. nov. is closely related to B. megasperma (on Viola spp.) and B. baudysii (on Berula erecta), but may be distinguished from the latter by its host plant, distribution, the polymorphous branches of sporangiophores and the shorter ultimate branchlets. New combinations of B. chrysanthemi-coronarii and B. artemisiaeannuae are transferred from the genus Plasmopara and Peronospora respectively. The common important characteristic of these two new combinations is the swollen ends of the sporangiophores. Differences between these new combinations and their related species are also discussed. Chinese and Latin diagnoses are given for the new species. Type specimens of the new species are deposited in Sichuan Agricultural College, Ya'an Sichuan, China.