“…Recently, novel functions of AOS have been investigated. Besides arresting pathogen proliferation in planta, AOS are involved in cell wall reinforcement (Olivain et al, 2003), callose deposition (Huckelhoven et al, 1999), and acts to signal molecules in systemic translocation of acquired resistance (Bolwell et al, 1995(Bolwell et al, , 1998Tenhaken et al, 1995;Wojtaszek, 1997;Alvarez et al, 1998;Chamnongpol et al, 1998). Similar to previously known plant defense activators, methyl viologen and mercuric chloride promote oxidative damage and chlorosis-induced plant defense responses (van Loon, 1975;Lund et al, 1993;Strobel and Kuc, 1995).…”