Ye to get 500g/m2 will most likelly take 1000+ W lights and a SoG from clones not seeds with most strains.
From seeds you can grow about 8-10 plants max I would say that MIGHT get u close to 500G if u can keep canopy even and light it very very well.
But... from those you natrually get clones to make a mother or two for you next grow and then u can SoG 20-40 plants on a square meter and if managed (and lit) well that will get you around those numbers without going to extremes such as using CO2 enrichment.

Puffzter
Puffzter Reviewed by Puffzter on . Silly Yeild Question im looking @ seeds and stuff online, for possible future purchasing (although am a little skeeved out by the illegality of mailing the stuff...) and under all the information for a given strain of seed there is always some statistics about the strain... how tall it will grow, if it's a high or a stoned feeling, and then it gets to the yeild, and it will say something like 500 g/m2... (grams per meter squared???) WTF does that meeeann?? is that like 500 grams of usable weed per meter, or Rating: 5