Translation:The apples on the plate are ours.
Pardon me for my zombie post, but I had the same question, and do not see an answer here, so I wouldn't mind bringing this one back to life.
My interpretation, in lieu of an authoritative response, is 'pe farfurie' refers to apples sitting on a plate. 'de' means from or shows possession. 'de pe' literally means 'from on', perhaps as in 'from on the couch' or just 'from the couch'. 'Take the pillows from the couch' could be said as 'Take the pillows off the couch', so in that example, 'de pe' can be said to mean 'off'.
In this case, I don't think that 'off' applies. I think the intent is that the apples are ours, even if they continue to be on the plate. However, saying 'the apples of the plate' is not as accurate, and may even be grammatically incorrect. So the apples that are ours at the ones that are 'of or belonging to' 'on the plate'.
It's not always satisfying to try to interpret the word for word translation of a statement from a foreign language. In Chinese, for example, we often see constructs such as 'fast of/belonging to car' or 'blue of/belonging to shirt', where it would be in error to say simply 'fast car' or 'blue shirt'