Tuber disks of five potato cultivars, each compatible to the fungus race used, were treated with cell‐free homogenate or lipophilic material obtained from the mycelial mat of Phytophthora infestans. On the effect of treatments, the various cultivars reacted in different manners as regards tissue necrotization and accumulation of phytoalexins rishitin, lubimin and phytuberin. No correlation was found between the extent of tissue necrosis and the level of phytoalexins. Each potato cultivar had a capacity for producing sesquiterpene phytoalexins even if the visible hypersensitive response (tissue necrosis) did not occur. It was concluded that there are compounds of pathogenic origin that induce phytoalexin accumulation as well as necrotization in plant tissues. The expression of necrotization mainly depends on different sensitivity of potato cultivars to treatments. The rate of phytoalexin accumulation would represent a potential for general resistance.
|Number of pages||9|
|Journal||Journal of Food Safety|
|Publication status||Published - Dec 1977|
ASJC Scopus subject areas
- Food Science