and Paolo Rapisarda. Previous studies speculated on the existence of an inverse relationship between the available nitrogen and the accumulation of defense-related secondary metabolites in plants [1], as a consequence of C:N ratio unbalance. According to this hypothesis, the lower nitrogen contents of organically grown plants lead to a shift from the N-containing compounds to the production of carbonrich defense-related phenylpropanoids. It has been also suggested that this behavior is

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... y linked to the increased resilience to pest attacks and damage exerted by organic plants [2][3][4]. Recent research [5] showed that long-term organic fields have been associated with no consistent difference in nitrogen and carbon content, nor in C:N ratio, between the organic and conventional