First... do you have a significant investment in time and data into JDOffice, or are you just getting started with it?   If the latter, there is a pretty good chance that any other program you have been using can write setup and Rx cards for your GS1.    If the former, your choice is tougher, but at some time, you will have to concede that JDOffice is a frozen application, and you'll need to move to some other solution (of which Apex is one option).

The reason that I ask is that you say "... from another source".   This implies that there is some other software tool being used.   Or maybe you are just getting Rx's from a crop consultant?

Here's the deal on JDOffice.   For Rx work, it uses the concept of "management zones".  It can't create them, but it can import polygon shapefiles that can be called management zones.  When you do this, you loose any values associated with the shapefiles.   You can't import "30,000 seeds per acre".   As I recall, you will have to manually go back in and tag all of the zones you want to be 30,000 seeds per acre as something like "Zone A".   Then you create a reclassification table that says all "Zone A" polygons get 30,000 seeds per acre.   It's been a couple of years since I took any data into JDOffice, but I think what I have described is close.