Study of flower and corm quantitative characteristics of saffron (Crocus sativus L.) ‎under organic, biological, and chemical nutrition systems in Gonabad area

In order to evaluation the response of saffron to different manure, biological and chemical fertilizers, an ‎experiment was carried out as split-plot based on randomized complete blocks design with three replications in ‎Research Farm of Gonabad Agriculture Jihad during 2015-2016 and 2016-2017 growing seasons. Main factor ‎was 60 t/ha manure, and no manure application, and sub factor concluded of control (no fertilizer use), nitroxin ‎‎(5 L/ha), biophosphorus (3 L/ha), biosulphur (5 kg/ha), humic acid (10 kg/ha), and chemical fertilizer (150, 100, ‎and 100 kg/ha urea, triple superphosphate, and potassium sulfate). Experiment results indicated that interaction ‎effect of manure and biological and chemical fertilizers on fresh flower yield, fresh and dry stigma yield was ‎significant. The highest fresh flower yield (181 kg/ha) achieved by biophosphorus along with application of 60 ‎t/ha manure. Fresh stigma yield in chemical fertilizer under manure application treatment showed the highest ‎increase (mean yield of 10405 g/ha). While, dry stigma yield due to biophosphorus application obtained the ‎highest value (5351 g/ha). The effect of manure on corm traits was significant. Corm number per unit area and ‎corm yield showed 19% increase in second year due to manure application than control. Among biological and ‎chemical fertilizer treatments, the highest value of corm number (440 corm/m2) and corm yield (4401 kg/m2) ‎was obtained due to biophosphorus application. Based on obtained results, combined application of ‎recommend manure with biological fertilizers especially biophosphorus under climatic and edaphic conditions ‎similar to this experiment area is recommended. ‎