In Great Britain and/or Ireland:
Foodplant / feeds on
Cylindrocarpon anamorph of Cylindrocarpon olidum var crassum feeds on root of Cactaceae

Foodplant / pathogen
colony of Drechslera dematiaceous anamorph of Drechslera cactivora infects and damages live stem of Cactaceae

Foodplant / pathogen
colony of Erwinia carotovora infects and damages stem of mature of Cactaceae

Foodplant / gall
Heterodera cacti causes gall of cysted root of Cactaceae

Foodplant / gall
Meloidogyne causes gall of root of Cactaceae
Other: major host/prey

Foodplant / saprobe
immersed, but more or less prominent pycnidium of Phomopsis coelomycetous anamorph of Phomopsis cacti is saprobic on dead stem of Cactaceae

Foodplant / sap sucker
Pseudococcus sucks sap of live green part of Cactaceae

Foodplant / sap sucker
Rhizoecus sucks sap of live stem base of Cactaceae
Other: major host/prey