Sick leave on Phrag. Eumelia Arias... Advice needed!

[John M]

According to the articles I have read, the ASA itself does work against the infection, but induces the plant to activate a defense metabolism producing metabolites that work against the infection. Only very low concentrations of ASA are needed for this.... One of the cases they studied was on trees in the jungle, which (when attacked by caterpillars) produced those defense mechanisms, including as well the production of ASA and some volatiles. The presence of ASA in the ground (due to fallen leaves) and/or the volatiles in the air, were sufficient to induce the activation of the defense mechanism in all trees around the infected one...

I think you found the same study that I found on the Internet. The ASA doesn't itself kill the pathogens, it boosts the "immune response" of the plants to the presence of the pathogens.

Ruth, I cut away all affectdd tissue and spray thoroughly just once. Then, I watch the plant very closely. If I notice any more discolouration that looks like the return of the Erwinia, I spray again. Over all, most plants don't need the second spraying and those that do, so far, have managed to shake off the rot with just two applications. In the past, I've had plants that get Erwinia, for whatever reason...and no matter how much of the plant I removed and dusted with cinnamon or sulfur, the rot came back and killed more of the plant. Some plants simply ran out of healthy leaves to become infected. Of course, with no leavs left, that means the plant was dead.

 

[Ruth]

Thanks for the info, I have paph that I am going to try it on. Hopefully it isn't to far gone.