agent [47], together with umbelliferone to the seedlings of barley and garden cress.
In all naproxen-treated acceptor plants, the concentration of the hydroxylated
derivatives of the imported umbelliferone was massively decreased. These results
indicate that the hydroxylation of the umbelliferone imported into the barley and
garden cress acceptor plants is catalyzed by a cytochrome P450 enzyme.
5
Conclusions
The insights displayed in this treatise outline vividly that the phenomenon of
horizontal transfer of natural product is far more prevalent than initially assumed.
Meanwhile, there is no doubt that in addition to alkaloids, also other natural products
are transferred from donor to acceptor plants.
Moreover, the widespread uptake of natural products from the soil requires
a reevaluation of the classical definition of xenobiotics. Up to now, xenobiotics are
defined as “non-natural substances,” which are “foreign to the plants” [48, 49].
Indeed, the substances taken up in the course of horizontal natural product transfer
are “foreign” to the acceptor plants, but they represent natural products. Accordingly,
a new definition, or at least a differentiation of the term xenobiotics, is required.
The perceptions that vital and living plants do incidentally release typical
secondary metabolites into their environment, which subsequently are taken up
from the soil by other plants, necessitate a reconsideration of our understanding of
plant-plant-interactions. Up to now, only “typical allelochemicals,” i.e., substances,
which exhibit certain significance within plant-plant interactions, e.g., by inhibiting
the growth or the germination of potential competitors, have been considered in this
context. Now, we are aware that a random exchange of natural products between
living plants – also between individuals of different species – is quite common.
These insights should improve our understanding of the evolution of allelochemicals
and thus, the interactions between plants in general.
A further aspect of the outlined transfer of natural products from living donor
plants concerns several hitherto unexplained processes related to beneficial effects of
crop rotations or the co-cultivation of certain vegetables. Based on the coherences
outlined, the exchange of natural products between vital plants could be the bases for
new explanations of these ambiguous phenomena.
References
1. Inderjit, Duke SO (2003) Ecophysiological aspects of allelopathy. Planta 17:529–539
2. Bertin C, Yang X, West LA (2003) The role of root exudates and allelochemicals in the
rhizosphere. Plant Soil 256:67–83
3. Kalinova J, Vrchotova N, Triska J (2007) Exudation of allelopathic substances in buckwheat
(Fagopyrum esculentum Moench). J Agric Food Chem 55:6453–6459
4. Willis RJ (1985) The historical bases of the concept of allelopathy. J Hist Biol 18:71–102
5. Trapp S, Legind CN (2011) Uptake of organic contaminants from soil into vegetables and fruits.
In: Swartjes FA (ed) Dealing with contaminated sites. Springer, Dordrecht
18 Horizontal Natural Product Transfer: A Novel Attribution in Allelopathy
437
In all naproxen-treated acceptor plants, the concentration of the hydroxylated
derivatives of the imported umbelliferone was massively decreased. These results
indicate that the hydroxylation of the umbelliferone imported into the barley and
garden cress acceptor plants is catalyzed by a cytochrome P450 enzyme.
5
Conclusions
The insights displayed in this treatise outline vividly that the phenomenon of
horizontal transfer of natural product is far more prevalent than initially assumed.
Meanwhile, there is no doubt that in addition to alkaloids, also other natural products
are transferred from donor to acceptor plants.
Moreover, the widespread uptake of natural products from the soil requires
a reevaluation of the classical definition of xenobiotics. Up to now, xenobiotics are
defined as “non-natural substances,” which are “foreign to the plants” [48, 49].
Indeed, the substances taken up in the course of horizontal natural product transfer
are “foreign” to the acceptor plants, but they represent natural products. Accordingly,
a new definition, or at least a differentiation of the term xenobiotics, is required.
The perceptions that vital and living plants do incidentally release typical
secondary metabolites into their environment, which subsequently are taken up
from the soil by other plants, necessitate a reconsideration of our understanding of
plant-plant-interactions. Up to now, only “typical allelochemicals,” i.e., substances,
which exhibit certain significance within plant-plant interactions, e.g., by inhibiting
the growth or the germination of potential competitors, have been considered in this
context. Now, we are aware that a random exchange of natural products between
living plants – also between individuals of different species – is quite common.
These insights should improve our understanding of the evolution of allelochemicals
and thus, the interactions between plants in general.
A further aspect of the outlined transfer of natural products from living donor
plants concerns several hitherto unexplained processes related to beneficial effects of
crop rotations or the co-cultivation of certain vegetables. Based on the coherences
outlined, the exchange of natural products between vital plants could be the bases for
new explanations of these ambiguous phenomena.
References
1. Inderjit, Duke SO (2003) Ecophysiological aspects of allelopathy. Planta 17:529–539
2. Bertin C, Yang X, West LA (2003) The role of root exudates and allelochemicals in the
rhizosphere. Plant Soil 256:67–83
3. Kalinova J, Vrchotova N, Triska J (2007) Exudation of allelopathic substances in buckwheat
(Fagopyrum esculentum Moench). J Agric Food Chem 55:6453–6459
4. Willis RJ (1985) The historical bases of the concept of allelopathy. J Hist Biol 18:71–102
5. Trapp S, Legind CN (2011) Uptake of organic contaminants from soil into vegetables and fruits.
In: Swartjes FA (ed) Dealing with contaminated sites. Springer, Dordrecht
18 Horizontal Natural Product Transfer: A Novel Attribution in Allelopathy
437