The other possible pathogen is Pantoea agglomerans , which is very common in soils, but usually not pathogenic. We are always interested in learning about more cases of stem gall here in Wisconsin or elsewhere. We are trying to figure out which environmental conditions are most conducive to stem gall. Pesticides are generally useless for bacterial gall diseases, so we need to figure out which cultural practices influence disease. If you see symptoms this year, I d be interested in hearing from you, and possibly getting a sample for analysis.
P is very important to plant metabolism.
It is critical to transferring three carbon sugars from the chloroplast into the cytoplasm where it can be used for metabolism or growth or can be exported to other organs. There are some guidelines, but the research behind them is tenuous. We also know that H 2 PO 4 - reacts readily with iron, aluminum and manganese ions in soils to form insoluble compounds and that these reactions occur rather quickly. Frequent light application of P is better than one or two large doses. Not that I know of.