An interesting e-mail from Stu:
I've just read on Wikipedia that "Emmerdale Farm" was modelled on the Irish soap "The Riordans". This is not evident from any Emmerdale material I have from the 1970s or 1980s. Although the production team may have visited "The Riordans" set and location to gain insight into filming in a farming location, isn't "modelled on" a bit strong? After all, "The Archers", the BBC radio soap based on a farming family and a village, has been running since 1951. So the basic idea can hardly be said to have come about via "The Riordans".
I really don't know, Stu. I hadn't read that information until recent years on Wikipedia. If anybody has any further insights, please drop me a line and I'll pass it on to Stu.
Incidentally, I recall The Riordans being shown briefly in my ITV area years ago. I thoroughly enjoyed what I saw of it.