Sugarcane is one of the most high value crops of agronomic and economic importance enjoying the largest scientific and technological attention in field and factory. It is one of the efficient users of solar energy but sensitive to soil aeration, radiation intensities, temperature and ageing factors when water and nutrients are freely available. It has a long history of chasing the theoretical limits of productivity thru research on all branches of Science. A relook at the theoretical maximum yield is attempted with new data on Net Primary Production (NPP) from solar radiation incident on earth through satellite studies. Recent studies have shown Net Primary Production can reach a level of 200 t C ha-1yr-1 (roughly 450 t bio-mass ha-1yr-1) which is roughly two times the other estimates.( delucia et.al ). An attempt to understand the limiting factors to get nearer to maximum yields is made in this paper.

Keywords : Limiting Factors; Theoretical Maximum Productivity.