How can I purchase plot in green zone

Hi Sir, I m looking to purchase plot in pune. But came to know that if i purchase 1 guntha 7/12 fer-far will not done on my name as per gov rules. Only separate registration (kharedikhat)can be done. Is kharedikhat legal? If I purchase 1 guntha, by law who will have full rights of property, me or whos name on 7/12? is it correct once residence population increases in green zone that will converte in residence zone. In future Once the gov start issue 7/12 for less than 11 guntha. Will my name come on 7/12 automatically or will i requre permission from previous owner?