In order to investigate the effect of concentration and time of supplementary nitrogen fertilizer spray on growth indices of rapeseed (cv. Hyola 401). a field experiment was conducted at Rice Research Institute of Iran as a randomized complete blocks design with 16 treatments and 3 replications in 2008-2009. The treatments included concentration of nitrogen fertilizer (urea) at two le... https://www.smokeaers.shop/product-category/bongs/