S. Schneidermuller et al., ROLE OF SALICYLIC-ACID AND INTRACELLULAR CA2-CULTURE( IN THE INDUCTION OF CHITINASE ACTIVITY IN CARROT SUSPENSION), Physiological and molecular plant pathology, 45(2), 1994, pp. 101-109
Treatment of carrot suspension culture with a fungal cell wall prepara
tion induced the production of chitinase. This treatment also caused a
n accumulation of salicylic acid both in the cells and in the extracel
lular medium. Culture medium of induced cells, which contained elevate
d levels of salicylic acid, was able to induce chitinase activity in a
non-induced suspension culture. Exogenous supply of authentic salicyl
ic acid induced chitinase activity in carrot cells more rapidly than t
he fungal cell wall. Removal of extracellular Ca2+ by treatment with t
he calcium chelator, EGTA [ethylene glycol bis(beta-aminoethyl ether)N
,N'-tetraacetic acid], abolished the elicitor-mediated production of b
oth salicylic acid and chitinase. Verapamil caused similar effects, wh
ereas the addition of the Ca2+ ionophore A23187, enhanced these cellul
ar responses in the absence of elicitor. These observations suggest th
at Ca2+ plays an important role in the induced production of chitinase
and salicylic acid.