For example , silencing phenylalanine ammonia lyase ( PAL ) , an enzyme synthesizing precursors to SA , reduces SAR .
For example , silencing phenylalanine ammonia lyase ( PAL ) , an enzyme synthesizing precursors to SA , enhances herbivory resistance against insects .
For example , silencing phenylalanine ammonia lyase ( PAL ) , an enzyme synthesizing precursors to SA , reduces SAR but enhances herbivory resistance against insects .