CROWN AND ROOT ROTS OF TABLE GRAPES CAUSED BY PHYTOPHTHORA SPP. IN CHILE

Phytophthora crown and root rot of grapevine (Vitis vinifera L.) occur s frequently in Chile, where grapes are cultivated on their own roots. P. cinnamomi, P. cryptogea, and P. drechsleri were isolated from dise ased root or crown tissue of the table grape cvs Flame Seedless, Itali a, Red Globe, and Thompson Seedless with P. cryptogea being the most f requently isolated species. These pathogens were identified on the bas is of standard morphological and cultural features and were compared b y SDS-PAGE profiles of mycelial proteins. All isolates were pathogenic on 1-year-old cane segments and 1-year-old rooted grapevines of cvs T hompson Seedless and Red Globe. The latter cultivar was more susceptib le than Thompson Seedless. P. cinnamomi and P. cryptogea have been ass ociated with root rot of grapevines elsewhere, but this is the first r eport of P. drechsleri as a pathogen of grapevines and the first repor t of Phytophthora spp. affecting table grapes in Chile.