Summary of Prevention and Treatment Methods and Practical Experience for Stem Rot

In April this year I bought six Guanyao Mei orchid seedlings, and they even came with a few buds. Since Guanyao Mei is a shy-flowering type and does not bloom easily, generally only when there are many seedlings can it bloom! So I bought a clump of connected plants! After disinfecting, I planted them. The potting medium used was Xiantu and Zhijinshi (about half each) with a little snakewood added. They grew normally, and the few buds gradually grew into half-grown seedlings! They also got through the severe midsummer heat without trouble! But when I had kept them until mid-August, I found that on one of the outermost old seedlings, several leaves began to turn yellow from the base up to 3-5 cm along the leaf and gradually became dark brown; they broke at a touch. Checking materials and books, I suspected stem rot, so I repotted, removed the diseased areas, disinfected the potting medium and the remaining seedlings, and replanted them! For a few days after planting there was nothing unusual! But after ten days, another old seedling that had originally been next to the diseased one showed the same condition as above! I likewise removed it, disinfected the potting medium and the remaining seedlings, and replanted them! This repeated over and over, with one seedling collapsing every 7-10 days! Today it was the same situation again, and one old seedling plus one half-grown seedling collapsed (photo)! I had just finished dealing with it! In total, five old seedlings have collapsed, and the three half-grown seedlings connected to them are done for as well! As of today there is still one old seedling and one half-grown seedling left (photo)! There is nothing more to be done! Whether the remaining two seedlings can survive and whether they have been infected all depends on luck! Yesterday at theorchidshop I talked about this situation with fellow orchid growers, and it happened that I also noticed a pot of fiveorchidseedlings in the shop had an old seedling with this condition, so I asked the shop owner to deal with it on the spot! He hadgrown orchidsand sold orchids for more than ten years and had experience handling this kind of thing. Several fellow orchid growers watched. First remove the diseased old seedling and check whether the connection point is white! After removing the diseased seedling, the connection point was found to be dry and black, and he said it might have already spread to the next old seedling! So he removed another old seedling 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 yet! It should be fine now. Then disinfect and dry it, throw away all the potting medium! Replace it with new potting medium and replant. Summary: I will not discuss the pathology; fellow orchid growers such as Xinxing have already explained it very clearly! I am only describing the process and how to handle it. There are lessons to be learned in it, to draw the attention of fellow orchid growers! From when I discovered the first diseased seedling to now, when there are still two seedlings left, the key problem was that I handled it incorrectly and did not promptly deal with the connected old seedlings (which looked like good seedlings but had actually already been infected). I was too soft-hearted and always held onto a wishful thinking mentality! This caused one seedling to infect another! It is better to remove two extra seedlings than to lose the remaining ones! Also, pay attention to prevention in advance; once disease is discovered it is already late! Even if cured, it is a narrow escape from death! In ordinary times, management should be scientific. Excerpted from "OrchidTreasure Book" by Jia Jianhua