BCSS - Forum

Can anyone tell me what this ugly looking blight is on my Lopophora, it's been growing up from the bottom, doesn't appear to be rot - or at least the cactus is still solid, hard & not squishy. Cactus has been dormant & without water since mid-Sept.
Any ideas on what it is & how to teat it, or whether I should cut off the loph pups before it spreads to them?






Thanks

It doesn't look good. If it is continuing to progress I think I would do as you suggest and remove one of the pups. It is not an ideal time to root offshoots but you might find that it already has some roots. Leave it to callous then put it on some porous substrate containing little if any moisture. You might have to wait until next year for there to be any sign of new roots. As to the cause of the problem, I've no idea.

I would try cutting out the diseased areas and seeing if you can get to clean (green) tissue. If so, dust the cut with funicide and leave to dry. This will work unless the rot has started deep within the body. Lophophoras are very capable of growing out of disfigurement and in a year or two could look good and healthy again.

Slug or snail damage? It's in quite a large pot for a small plant.
Stuart.

Not slug or snails, I know what that looks like.

I may try unpotting it & seeing if the roots/below soil-line are damaged & possibly then try either cutting off damaged parts or removing pups, but there's a lot of damaged parts so I'm cautious about that.

As the unidentified blight continued to grow - not much & slowly, but still growing a bit - I examined the base of the plant and cut off the blight.
The roots & base of the cactus were all solid and the blight not very deep & not extending beyond the visible surface portion of the cactus. I was able to cut it off & get to wholly green tissue without going much more than 4 or 5mm deep. Blighted bit was dry & crusty when examined.
I've now treated the cactus with sulphur and am leaving it to scab over & hopefully recover.
I'm still very curious to find out what this was and what's caused it as it was very unsightly & the process of cutting it off hasn't made the Lophophora any prettier so I definitely don't want it appearing in any of my others. Fortunately it appears to be an isolated case.

Undersides of the cut off blighted parts.

Looks like rot to me. Probably caused by the pot being far too large. The plant can't cope with that amount of wet compost. My experience of Lophs is that they do best when being fairly tight in their pots.

I would agree it being rot, overpotting may have caused it. You could argue that my plant pictured below is overpotted (the largest head is 3 inches across) but it's difficult to find a pot big enough to accommodate the root. It gets watered maybe once a month in summer and then only enough to wet the top inch of soil. Watering results in it bringing out the flush of flowers. This plant has blemishes (you can just see them on the small head above the twin flower in the middle) and they do grow out over time. Keep it dry above 10 degrees over winter and start watering carefully from about April as the weather warms up.

MikeDom wrote: ↑Sun Oct 28, 2018 12:29 pmKeep it dry above 10 degrees over winter and start watering carefully from about April as the weather warms up.

Mine has happily coped with winter temperatures down to 3 deg C without any problem over several winters. I agree that the plant should be kept dry in winter.

I have seen this type of lesion on a couple of my lophophoras and have no idea as to the cause. It is dry and mainly on the surface. It is some sort of damage and not a rot. It almost looks likes the lesions caused by red spider mite, which the genus is very prone to, but that always starts in the juicier apical part of the plants. Left to their own devices, the plants grow out of it over a period of a couple of years.