I've heard (and experimented with) plenty on that subject, but in a laboratory environment. Inducing plant responses does seem like a good idea, but I do have a few doubts about it.
For one, induced defenses in plants entail fitness costs. A plant can't use energy to both defend itself and grow, it must make a choice. That's why the induced defenses are only activated when need. So I would think that by artificially inducing a plant over a prolonged period of time it would result in a healthier plant, but also a plant who is not growing as well as it should. I have not looked for data to back this up (but I know there is plenty of literature on the subject), this is what I think based on my knowledge of plan denfenses.
The other thing that bothers me is that by inducing and maintaining salicylic acid dependent SAR, it could make plants more susceptible to chewing insects and necrotrophic diseases. The SA pathway is involved in defense against sucking insects (like aphids) and biotrophic diseases while another phytohormone pathway, jasmonic acid, defends against the chewers (like caterpillars) and necrotrophic fungi. The problem is that SA and JA are antagonistic in the plant, so that plant can't activate both systems at once. So while a plant may be protected from some things by adding SA, it remains more susceptible to others. The extent to which a plant is susceptible is not quite known. That happens to be the research project I'm working on right now.
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Camille
Completely orchid obsessed and loving every minute of it....
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Last edited by camille1585; 09-12-2009 at 07:29 AM..
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