As far as I know Egypt, under the Ptolemies, became famous in Hellenistic world for vast agricultural production due to the strict and harsh administration installed there by Greeks.
Still I wonder - was the Roman administrative system different enough from the previous Greek one to cause changes in economy of Egypt? Was the Roman economic system in some ways more effective in the short- or long-term?
Of course, there must be some complications to that question posed by some level of political disturbance of Ptolemaic Egypt in II-I centuries BC which, I guess, coupled with the economic blunders of policy by the first Ptolemies, somehow affected productivity in general. But to keep things simple, let's compare production of main agricultural staples (grain) during relatively peaceful times (let's say III century BC for Hellenistic Egypt and I-II centuries AD for Roman Egypt).