The effects of mother corm size, manure and chemical fertilizers on replacement corm criteria and yield of saffron (Crocus sativus L.)

The Mother corm size and nutrient management are the most important factors in relation to quantitative and qualitative characteristics of saffron (Crocus sativus L.). In order to investigate the effects of mother corms size, manure and chemical fertilizers on replacement corm criteria and yield of 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 2012 and 2013. The mother corm size (4g and lower (small), 4.1–8 g (medium), 8.1-12 g (relatively large) and more than 12 g (large)) and fertilizer sources (manure 25 t. ha-1, chemical fertilizer (N+P) and control) were the first and second experimental factors, respectively. The larger mother corms (8.1-12 g and more) significantly resulted in a greater number of flowers per m2, increased fresh flower and dry stigma yields. As observed in flower and stigma yields, replacement corm yield per m2 was significantly increased by larger mother corms. In addition, number and yield of replacement corm significantly affected by fertilizer sources.However, effect of manure on yield of replacement corm more than 8 g and total replacement corm yield was higher than chemical fertilizer (by 12.5 and 21.8 %, respectively). It seems the selection of appropriate mother corm (more than 8 g) and applying manure can result in reducing the problems caused by consecutive using of chemical fertilizers.