The study carried out on black clay loam soil revealed that considerably higher yield of sunflower realised with January 30th followed by January 15th as compared to February 15th sowing. This was due to higher leaf area, dry matter production, LAI, LAD, harvest index and ultimately better seed filling probably because of suitable temperature during crop growth period. Also that higher yield obtained at a population level of 0.83 as compared to 1.11 lakh plants per hectare was due to significantly higher leaf area and dry matter production per plant and higher harvest index. Hybrid BSH-1 outyielded variety Morden as it possessed higher leaf area and dry matter per plant, higher LAI, LAD, harvest index and longer reproductive period.
