These lessons in stem rot prevention and treatment must be remembered

In April this year I bought six Guanyao Mei plants, and they even came with a few shoots. Since Guanyao Mei is a shy-flowering type that does not bloom easily, usually only when there are many plants can it flower! So I bought a whole connected clump! After disinfecting, I planted them. The growing medium used was xiantu and zhijinshi (about half each) with a little snakewood added. Growth was normal, and the few shoots gradually grew into half-grown plants! They also got through the severe heat of midsummer smoothly! But when I had kept them until mid-August, I found that on one old plant at the very outer edge, several leaves began to turn yellow from the base up to 3-5 cm along the leaf and gradually became dark brown, breaking at a touch. Looking at references and books, I suspected stem rot, so I repotted the plant, removed the diseased areas, disinfected the growing medium and the remaining plants, and replanted them! For a few days after replanting there was nothing unusual! But ten days later, another old plant that had originally been next to the diseased one showed the same situation as above! I removed it in the same way, disinfected the growing medium and the remaining plants, and replanted them! This repeated over and over, with one plant collapsing every 7-10 days! Today it was the same situation again, and one old plant plus one half-grown plant collapsed! I had just finished dealing with it! In total, five old plants have collapsed, and the three half-grown plants connected to them are finished as well! As of today there is still one old plant and one half-grown plant left! There is nothing more I can do! Whether the remaining two plants can survive and whether they have been infected depends on luck! Yesterday at theorchidshop I talked about this situation with fellow orchid growers, and it happened that I also noticed that in the shop there was a pot of fiveorchidplants, and one old plant also had this condition, so I asked the shop owner to deal with it on the spot! He hasgrown orchidsand sold orchids for more than ten years and has experience handling this sort of thing. Several orchid friends watched. First remove the diseased old plant and check whether the connection point is white! After removing the diseased plant, we found that the connection point was already dry and black, and he said it might have spread to the next old plant! So he removed another old plant that looked like a good plant. It could be seen that the connection point was white, so he said it should not have spread here! It should be no problem now. Then disinfect and dry it, throw away all the growing medium! Replace it with new growing medium and replant it! Summary: I will not discuss the pathology, as Xinxing Orchid Friend and others have already explained it very clearly! I will just describe the process and how to handle it. There are experiences and lessons in it, to draw orchid friends' attention! From when I discovered the first diseased plant to now, when only two plants remain, the key mistake was handling it incorrectly and not promptly dealing with the connected old plant (which looked like a good plant but had actually already been infected). I was too soft-hearted and always held on to a wishful thinking mindset! This caused one plant to infect another! It is better to remove two extra plants so as to save the remaining plants! Also, pay attention to prevention in advance; once disease is discovered it is already too late! Even if cured, survival is a narrow escape! In ordinary times, one should manage scientifically.