evaluation the effect of nono-iron fertilizer in compare to iron chelate fertilizer on qualitative and quantitative yield of saffron

to evaluate the effect of nano-iron chelate and also to make a comparison with effect of eddha iron chelate on saffron, an experiment was conducted as factorial based on a randomized complete block design with six treatments and three replications in shahed university, tehran in 2011 and 2012. treatments included iron fertilizer (nano chelate and common chelate) in three levels (zero, 450 and 900 g/hairon). the results showed that all traits except carotenoid, chlorophyll a concentration and leaf width affected by type and amount of iron fertilizer or their interaction. saffron yield increased by both iron sources (about 50 percent). application of 10 kg/ha of nano-iron chelate fertilizer, increased dry stigma yield, fresh flower weight, flower number, leaf number, main corm diameter and total corm weight of saffron compared to control though they were in some cases two times compared to control. totally, results indicated more effectiveness of nano-iron at five kg/ha nano iron chelate fertilizer and 10 kg/ha common iron chelate fertilizer had the same effects on most of the traits. it seems that soil fe deficiency and nano chelate efficacy in slow releasing may lead to saffron yield increment.