Dietrich, R.; Ploß, K.; Heil, M.:

Constitutive and induced resistance to pathogens in Arabidopsis thaliana depend on nitrogen supply.

In: Plant, Cell & Environment, Jg. 27 (2004), S. 896-906
Zeitschriftenaufsatz / Fach: Biologie
Knowledge about the induced pathogen resistance of plants
is rapidly increasing, but little information exists on its
dependence on abiotic growing conditions.
plants that had been cultivated under different
nitrogen regimes were treated with BION
, a chemical
resistance elicitor. The activities of three enzyme classes
functionally involved in resistance (chitinase, chitosanase
and peroxidase) were quantified over 8 d following treatment
as resistance markers. Constitutive levels of three
markers and the induced level of peroxidase and chitinase
activity were significantly lower under limiting nitrogen
supply. Under such conditions the increase of chitosanase
activity after resistance induction was severely delayed,
although the induced maximum activity of chitosanase was
not significantly affected. Total soluble protein content
decreased during the first 12 h after resistance elicitation.
Thereafter, the induced plants cultivated under high N conditions
reached higher protein contents than controls,
whereas N-limited induced plants continuously had
reduced protein contents. A plant’s investment in resistance-
related compounds can be severely constrained
under limiting nitrogen supply.