Articles
DOES THE RESEARCH ON PLANT PHENOLS HOLD OUT PROSPECTS IN INTEGRATED PLANT PRODUCTION? – A BIOCHEMIST’S VIEW
Such systems may appear suspicious to the novice in this field with only marginal relevance for disease management.
However, the accumulation of phenolics in the plant cell wall at the site of infection is a widespread phenomenon, and the extent as well as the speed of accumulation has been frequently discussed in the context of disease resistance expression.
Accordingly, control of the accumulation rate at the enzymatic and molecular level deserves particular attention, and inducible cell cultures simplify the investigation of these questions.
Using these model systems it is often possible to directly identify enzymes which participate in the disease resistance response.
These enzymes can be isolated and their regulation at the protein level can be investigated.
By employing immunocytochemical techniques, the localization of enzymes in infected and healthy plants and their relevance for resistance can be established.
Molecular biological investigations leading to the isolation and cloning of the respective genes is also much easier using inducible plant cell systems.
The DNA sequences coding for enzymes of the inducible resistance response can then be implemented as probes for screening plants for these enzymes either directly or in combination with PCR. This would be an aid for contemporary breeding programs.
A further use for isolated genes is the introduction and expression of these genes in plants which normally do not have these activities.
The resulting transgenic plants would also contribute to a conventional breeding program.
Broad plant resistance against phytopathogenic fungi is not always based on constitutive trails, and increasing the content of phenolic compounds in the plant cell walls of non-infected plants is not a suitable goal in resistance breeding.
Instead, the rapid mobilization of phenylpropanoid pathways is required solely