Sunflower Productivity UNDER Glasshouse Environment: A Simulation & FIELD Study.

Sunflower (Helianthus annuus L.) is a major oilseed crop not only in Pakistan, but also all over the world. It is much susceptible to climatic variables and hence climate could have significant effect on its production. The experiment was conducted during spring 2011 in greenhouse of Department of Plant Sciences, Quaid-i-Azam University, Islamabad-Pakistan. The effects of Nitrogen (N) and Plant Growth Promoting Rhizobacteria (PGPR) on growth and development of sunflower (Helianthus annuus L., var. Hysun-33) under natural environment were studied. The N use efficiency of sunflower crop grown under three N rates (N₁ = 0 kg ha^-1, N₂ = 120 kg ha^-1, N₃ = 240 kg ha^-1) and three PGPR levels (R₁ = 0 kg ha^-1, R₂ = 30 kg ha^-1, R₃ = 60 kg ha^-1) were investigated. This study presents results of a simulation study to evaluate the impact of projected climate change on sunflower in contrasting agro-environments in glass house environment by making different treatments within the model for various temperature and CO₂ levels. The OILCROP-SUN model that is part of DSSAT (Decision Support System for Agro-technology Transfer) has reasonably predicted phenology, crop growth, development, yield and yield components of sunflower crop. The simulation results showed that their is increase in CO₂ concentration from 360 ppm to 550 ppm has no affect on crop duration. On the other hand, leaf area index (LAI) that results in total dry matter (TDM), will increase with increased CO₂ concentration. Results of present study showed that, increasing temperature will shorten crop duration from planting to physiological maturity (with difference of almost 14 days in 2020's and 21 days in 2050's, respectively), thus retards the growth and development and ultimately decreased the yield than current situation at all the experimental locations of Punjab-Pakistan. Furthermore, for maximum economic benefits (maximum growth and development that’s lead to higher achene yield), application of 120 kg N ha^-1 was better under well irrigated conditions compared to other different N levels. Further research especially in the field of crop simulation modeling may be required in this area for sunflower crop to identify best agronomic management strategies in order to achieve high yield and profitable edible oil production of Pakistan.