I'll echo the above. Russians and Greeks should not be given fruit on a regular basis. Which doesn't mean they don't love it; they do. It's just not good for them.
It's a green stuff diet for them.
The Tortoise Table - Plant database is great for finding out recommended foods
These should be helpful to you too:
http://russiantortoise.net/russiantortoisediet.htm
http://russiantortoise.org/care_sheet.htm
http://www.turtlerescues.com/russian_tortoise_care.htm