Interactions in dual cultures of endophytic fungi with host and nonhost plant calli

Abstract

Undifferentiated plant cells may be used in simplified systems for studying the interactions between plants and fungi. We used plant calli for investigating the interactions between three endophytic fungi (Coniothyrium palmarum, Geniculosporium sp. and Phomopsis sp.) and their host and nonhost plants (Lamium purpureum and Teucrium scorodonia), showing that growth of these endophytes was specifically enhanced by calli of the host. Substance (s) secreted by the host calli were responsible for this growth response. The endophytes also secreted metabolites into the medium. These were toxic to the plant calli, irrespective of whether it was a host or nonhost interaction. Further tests demonstrated the nonspecific herbicidal nature of these substances.

Key Words:

• Coniothyrium
• Geniculosporium
• growth response
• herbicidal metabolites
• host specificity
• Phomopsis