Induction of pathogenesis-related proteins in germinating wheat seeds infected with Fusarium culmorum

The effect of Fusarium culmorum infection during the development of wheat seedlings was investigated. The fungal infection reduced the germination of inoculated caryopses in comparison with that of control seedlings; symptoms were clearly evident on seedlings growth. At the molecular level, F. culmorum infection caused the induction of a number of pathogenesis-related (PR) proteins. Two basic isoforms of beta-1,3-glucanase (PR2) and three basic isoforms of chitinase (PR3) were specifically induced upon infection, whereas several acidic and neutral glucanase and chitinase isoforms accumulate constitutively. These findings suggest that PR2 and PR3 proteins, besides their involvement in plant defense, may play a role also in the normal process of seed germination. In addition, infection by F: culmorum caused the appearance of wheatwins (PR4) and the increase of peroxidase (PR9) activity from the early stages of development of inoculated wheat seedlings. The coordinated induction of several PR-proteins with different action mechanism are part of the defense strategy that the plant activates for limiting the fungal colonization. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.