Cactus / grafted cauliflower

I grafted young seedlings of Ariocarpus retusus v furfuraceus cv Suguri cauliflower on pereskiopsis grafting stocks last year. They have grown well.
I grafted 24 more in this year.
When pereskiopsis lost leaves, the growing speed of the scion is reduced.
Some of leaves have turned color. I think they may loose leaves soon.