GENETICALLY-ENGINEERED BROAD-SPECTRUM DISEASE RESISTANCE IN TOMATO

Resistance in tomato to the bacterial pathogen Pseudomonas syringae pa thovar tomato requires Pto and Prf. Mutations that eliminate Prf show a loss of both Pto resistance and sensitivity to the organophosphate i nsecticide fenthion, suggesting that Prf controls both phenotypes. Her ein, we report that the overexpression of Prf leads to enhanced resist ance to a number of normally virulent bacterial and viral pathogens an d leads to increased sensitivity to fenthion. These plants express lev els of salicylic acid comparable to plants induced for systemic acquir ed resistance (SAR) and constitutively express pathogenesis related ge nes. These results suggest that the overexpression of Prf activates th e Pto and Fen pathways in a pathogen-independent manner and leads to t he activation of SAR Transgene-induced SAR has implications for the ge neration of broad spectrum disease resistance in agricultural crop pla nts.