SYSTEMIC APPLICATION OF L-PHENYLALANINE INCREASES PLANT-RESISTANCE TOVERTEBRATE HERBIVORY

The systemic application of L-phenylalanine (PHE), a phenolic precurso r, significantly increases the phenolic pool of oilseed rape (Brassica napus var. Bristol). In a two-choice test with captive feral pigeons (Columba livia), PHE-treated plants sustained significantly less damag e than control plants. This was supported by the results of behavioral studies, where video analyses showed that the PHE-treated plants rece ived significantly fewer pecks than the controls. This is the first re port of increased resistance to damage by a vertebrate pest following the systemic application of precursors for plant defense compounds.