I sent a couple infected leaf to a university, and it was diagnosed as fusarium. I google fusarium and some shows the same rot from the base of a plant. On the other hand since the rot is smelly and wettish, I have always thought it is bacterial infection. I have tried with Benlate (no more available), Terrazole, metalaxyl/mancozeb(=Ridomil), Kocide and pool chemical. I have always remove all the infected leaves to its base. Most of the fungicide are just preventative. But with the pool chemical (14% chlorine, applied at 0.5%) and immersed in that solution for 1 day does kill the bug. It may also kill the main growth (if the bug has gone through the crown, which will eventually kill the plant), but there are always new multiple growths shooting out. Is there a microbiologist here in this forum, who can advise further????