i have just noticed that the symbol for depletion mosfet and enhancement mosfet are the same in proteus. will this will not cause confusion to readers reading the schematic?
As long as the symbol netlists to the appropriate model, appearances are just that. But if you want your schematics to be more fully expressive, style points for you.
I think I've seen MOSFET symbols with the "channel" line dashed but that to me would imply enhancement mode (no channel until you provide gate drive).