растителни токсини

1
Most recent investigations have focused on induced, rather
than constitutive, plant defenses. Yet significant research has
helped to illuminate some of the principal characteristics of
constitutive defenses, including mechanisms of action and
synergistic effects, as well as strategies used by herbivores
and pathogens to circumvent them.
Addresses
Max Planck Institute for Chemical Ecology, Department of
Biochemistry, Winzerlaer Strasse 10, Beutenberg Campus,
D-07745 Jena, Germany
*e-mail: wittstock@ice.mpg.de
†
e-mail: gershenzon@ice.mpg.de
Current Opinion in Plant Biology2002, 5:
1369-5266/02/$ — see front matter
© 2002 Elsevier Science Ltd. All rights reserved.
DOI 10.1016/
S1369-5266(02)00264-9
Abbreviations
cytochrome P450scytochrome-P450-dependent monooxygenases
DIBOA 2,4-dihydroxy-1,4-benzoxazin-3-one
DIMBOA 7-methoxy DIBOA
Introduction
Plants synthesize a broad range of secondary metabolites,
including alkaloids and terpenoids, that are toxic to herbi-
vores and pathogens, and so are believed to act as defense
compounds. Classical examples of plants that are poisonous
to humans, such as poison hemlock, foxglove, and aconite,
demonstrate how well natural products can defend plants,
at least against mammalian herbivores. Defensive chemicals
have long been thought to be costly for plants because of
the resources consumed in their biosynthesis, their toxicity
to the plant itself or the ecological consequences of their
accumulation [1,2] (see also Heil, this issue). One way for
a plant to reduce these costs is to synthesize defense
compounds only after initial damage by a herbivore or
pathogen. This strategy is obviously risky because the
initial attack may be too rapid or too severe for such
damage-induced defenses to be deployed effectively.
Consequently, plants that are likely to suffer frequent or
serious damage may be better off investing mainly in