Here's an update on the
Yavia cryptocarpa seedlings I grafted in 2021. It's been a long time coming...
In the spring of 2022 I noticed both Yavia scions started growing roots while on their Pereskiopsis grafts.
June 2022:
The proliferous scion with many offshoots.
And the second scion with only one offset.
I decided to degraft both scions, thinking they had a good chance to establish themselves on their own roots.
This is a couple weeks after coring out the graft junction and leaving to heal.
The proliferous plant even started rooting from the cavity while it was drying.
Here they are a couple weeks after potting up. They seemed to be rooted into the substrate and were taking in water.
Here's the second plant. The main stem started to wrinkle and shrink, but the offsets remained plump, so I didn't think much of it.
The same plant several months later, at the end of the growing season, December 2022.
Obvious growth, but just as obvious, the main stem shriveled down even more.
The single-stemmed plant appeared not to have grown much, so I decided to unpot and check out the roots. This is February 2023.
Unpotted. The root system was smaller than expected but it appeared robust, fine root hairs and all. At this point it had been kept dry for over 3 months.
I potted it up and started watering with the rest of the collection several weeks later as spring started. I left the proliferous plant intact, deciding it was better to leave it alone since it had shown good growth months prior.
Unfortunately, neither plant reacted to water. Very slowly, all through the spring and going into summer, both plants kept shrinking.
I finally unpotted them in June 2023.
I was expecting rot but was surprised to find the roots nearly the same as they were 4 months prior, just dried up. You can see the main root still had a bit of succulence to it. However, the stem was completely desiccated and hard as a rock. I couldn't tear at it with my fingers. I discarded it.
Here's the other plant. Just as dried up as the previous one.
I found it bizarre how healthy the root system looked. No sign of rot anywhere and they were very plump.
One of the offsets was still pliable, so I cut it off to examine the insides.
There was dehydrated green tissue in the very center, but the rest was completely dried up. The base where it connected to the main stem was completely corked through, so it was cut off from water and nutrients.
I cut away into the main stem, removing tough, corky tissue that was uniform in color, until I found some softer tissue with some discoloration that I could more neatly cut a slice from.
I am not sure why these plants refused to come back from winter dormancy. I saw no signs of pests (though one did have a mite infestation that cleared up the previous winter while it was still grafted). I know this species normally has a massive taproot if left on their own roots. Maybe these degrafts did not like to be kept completely dry during the winter, since they only had diffuse roots and were deprived of their storage organ? The succulence of the roots above seems to refute that. Now, I did have these exposed to the sun all through the winter and part of spring, so sunburn could be suspected. But as soon as I noticed the shriveling, I moved them into the shade. And besides, we had an unusually cool spring with more days overcast than not. I think sunburn was unlikely? I also suspect dry rot. The orange/red discoloration I found was only at the base of the main stem, the tissue higher up was a uniform "dead-plant-tan" color. I have had experience with dry rot before. My grafted Mammillaria bertholdii, luethyi, and a white-flowering theresae succumbed to it. The tubercles dried up and fell off, while the stems shriveled and were completely orange, but dry inside. The rootstocks of each were unaffected. In the case of the Yavia, maybe it was affected by a different pathogen that doesn't discolor the tissue as it decays?
Now, I did graft offsets from both scions as backups.
But I was greedy and grafted one of the smaller offsets from the proliferous plant, not wanting to ruin the look. This was July 2022, a couple weeks after grafting on Harrisia jusbertii.
The graft took, but just barely. Since the scion was tiny, I figured I didn't need to hold it down while it fused. Obviously this was a mistake. Predictably, I ended up knocking the scion off the stock. I was too confident in the proliferous plant surviving and decided against grafting another offset from it. I am still kicking myself over that.
The second plant only had one offset on it and I did a better job of grafting it, using rubber bands to hold it down while it fused.
Here it is several months later, December 2022.
And here it is today, the only survivor.