PATHOGENESIS-RELATED PROTEINS IN BARLEY LEAVES, INDUCED BY INFECTION WITH DRECHSLERA-TERES (SACC) SHOEM AND BY TREATMENT WITH OTHER BIOTIC AGENTS

The perthotrophic fungus Drechslera teres, the causal agent of net blo tch disease in barley, induces the accumulation of pathogenesis-relate d (PR) proteins in barley leaves as shown by isoelectric focusing. The same protein pattern was also found in leaves treated with a toxin ex tract from the culture filtrate of D. teres as well as after infection with Erysiphe graminis f.sp. hordei or Puccinia hordei. Some of the p roteins induced by infection with D. teres were characterized as perox idases, beta-1,3-glucanases and chitinases by isoenzyme analysis. Immu nodetection following western blots demonstrated that the induced prot eins are the same as those that accumulate after inoculation of barley with E. graminis: basic PR-1a and b proteins, thaumatin-like (TL) pro teins, beta-1,3-glucanases and chitinases. The accumulation of PR-1 ty pe proteins, chitinases and TL-proteins was analysed quantitatively by ELISA. (C) 1996 Academic Press Limited.