Insect footsteps on leaves stimulate the accumulation of 4-aminobutyrate and can be visualized through increased chlorophyll fluorescence and superoxide production.

Abstract

A substantial literature has demonstrated that within 2 to 3 h of insect herbivory or mechanical damage, plants synthesize wound-induced proteinase inhibitors that inhibit digestion ([Bergey et al., 1996][1]; [Ryan, 2000][2]). In contrast, we demonstrate here that the simple non-wounding crawling of