| In addition to phytoalexin synthesis, the defense response of intact Citrus limon seedlings against Alternaria alternata involves both constitutive and induced enzyme activities such as chitinases (Ch) and ß-1,3-glucanases (Glu). A. alternata conidial germination was prevented by protein extracts from inoculated lemon seedlings, but also by extracts from mock-inoculated specimens. On the other hand, degradation of mycelia was accomplished only by protein extracts from inoculated seedlings. The presence of six Ch isoenzymes and of four Glu isoenzymes was detected in protein extracts from mock-inoculated seedlings. As a result of fungal inoculation, the isoenzyme pattern of Ch and Glu changed, making possible the detection of a new Ch isoenzyme and of three... |
