The effects of mother corm size and type of fertilizer on nitrogen use efficiency in saffron

Mother corm size and nutrient management are the most important factors in relation to nitrogen uptake of saffron (Crocus sativus L.). In order to investigate the effects of mother corms size and type of fertilizer on uptake and use efficiency of nitrogen in Saffron، a field experiment was conducted as factorial layout based on a randomized complete block design with three replications at Faculty of Agriculture، Ferdowsi University of Mashhad، Iran، during the years 2013 and 2014. The mother corm size (4 g and lower (small)، 4. 1–8 g (medium)، 8. 1-12 g (relatively large) and over 12 g (large)) and fertilizer sources (cow manure 25 t ha-1، chemical fertilizer (N+P) and control) were the first and second experimental factors، respectively. In both years، the larger mother corms (8. 1-12 g and more) significantly resulted in greater nitrogen content (g m-2) of replacement corms and whole plant of saffron. In addition، uptake and use efficiency of nitrogen were significantly increased with increasing mother corms size. In the first and the second years، nitrogen use efficiency in manure treatment was significantly higher than that of chemical fertilizer (by 21 and 61%، respectively).