TITLE	Occurrence of parasexual cycle in Phytophthora parasitica following protoplast fusion
AUTHOR	Y.H. Gu Department of Plant Pathology, Beaumont Agricultural Research Center, University of Hawaii at Manoa, Hilo, Hawaii 96720, USA W.H. Ko Department of Plant Pathology, Beaumont Agricultural Research Center, University of Hawaii at Manoa, Hilo, Hawaii 96720, USA
FULL TEXT	[in HTML format] [in PDF format]
ABSTRACT	Metalaxyl-resistant (Mr) and chloroneb-resistant (Cnr) protoplasts of Phytophthora parasitica were fused, with heterokaryon formation rates ranging from 2.6 × 10-3 to 8.2 × 10-3. The heterokaryosis was confirmed in six of seven putative heterokaryons by the production of both Mr zoospores and Cnr zoospores, and/or Mr + Cnr zoospores. The 7th putative heterokaryon produced only Cnr zoospores, probably because of the loss of the Mr chromosome during subculture. The heterokaryons produced normal-sized zoospores as well as large zoospores that were almost twice the size of normal-sized zoospores. Fifty percent of the normal-sized zoospores contained Mr and Cnr genes. The results suggested an occurrence of diploidization after karyogamy of the heterokaryon and thus demonstrated the completion of events leading to a parasexual cycle following protoplast fusion.
KEYWORD	Diploidization; Phytophthora parasitica; Parasexual cycle; Protoplast fusion;
ARTICLE INFO	Botanical Bulletin of Academia Sinica, Volume 41 Number 3 July 2000, page 225-230, 6 pages
PUBLISHER	Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, Republic of China