XVI International Botanical Congess

Cotton and tobacco plants were transformed with the following two antifungal genes: 1) a haloperoxidase gene and 2) a gene that codes for a synthetic, linear peptide (D4E1). In the presence of haloperoxidase two potent microbicides are formed û hypochlorous acid and peracetic acid. The synthetic peptide D4E1 kills germinating conidia by forming aqueous pores on fungal cell wall causing osmotic imbalance. Transgenic tobacco plants expressing either haloperoxidase or D4E1 showed enhanced disease resistance in planta against a fungal and a bacterial pathogen. Extracts from transgenic tobacco leaves or cotton embryogenic cells demonstrated a high degree of control against several pathogens. Antifungal assays with transgenic cotton plants are in progress.