Dendrobium care at 46 degree Celsius
 

what care want to take when we want to grow dendrobium in a condition where there will be temperature rise 46 degree Celsius at its peak summer time

Well, cool to intermediate will possibly turn their toes up. I get 47C here as the hottest (so far) and I have a couple that really are cooler types and aren't happy, and are possibly destined for the great compost heap.
All the warm ones tho seem fine. I have all mine on mounts, and they get 2 x 15 second sprays of very mild fert solution every morning.

They seem happy on that regime. I have them all in bright dappled shade.