Cellular Resistance in Rice to Cercosporin, a Toxin of<i>Cercospora</i>

Abstract

Four rice cultivars differing in resistance to Cercospora oryzae were examined for resistance to purified cercosporin, the red toxin secreted by the fungal mycelium. The cultivars were red rice (most resistant to pathovars of C. oryzae), Lemont and Leah (intermediate resistance), and Labelle (most susceptible). Resistance to the toxin was assessed in seedlings (inhibition of growth), leaves (chlorosis and necrosis), callus (inhibition of growth and hydrolysis of fluorescein diacetate), and cell suspensions (ion leakage). Toxicity of cercosporin depended on illumination (...)