Abstract
Lignin formation in the Japanese radish root was not initiated by the lignification-inducing factor (LIF) alone but initiated with increase of L-phenylalanine ammonia-lyase (PAL) activity which was enhanced by the presence of ethylene released from 2-chloroethylphosphonic acid (CEPA). When cucumber leaves were treated with CEPA after the treatment with LIF obtained from the homogenate of diseased tissues, lignification of cell walls occurred immediately, and resistance against Colletotrichum lagenarium was induced in the leaf tissues. These results imply that the action of LIF was activated by the presence of ethylene and caused lignin induction, which resulted in the prevention of fungal development by the formation of lignified cell walls.
