effects of nutrient management on flowe yield and corm characteristics of saffron (crocus sativus l.)

in order to understand the effects of different organic and chemical fertilizer on stigma yield, corm characterstics and leaf dry matter yield (as a forage) of saffron (crocus sativus l.), an experiment was conducted in the research station of faculty of agriculture, ferdowsi university of mashhad, iran, in 2005-2009; as a randomized complete block design with 12 treatments and three replications. experimental treatments included of: different levels of chemical fertilizers (250 kg triple superphosphate + 50 kg urea/ha; 250 kg triple superphosphate +100 kg urea/ha; 250 kg triple superphosphate + 300 kg urea/ha), cow manure (20, 40 and 60 t/ha), sheep manure (20, 30 and 40 t/ha) and hen manure (5, 10 and 15 t/ha). results showed that the highest fresh flower (315 kg/ha) and dry stigma yield (3.8 kg/ha) were obtained from chemical fertilizer (300-250 kg/ha urea- triple superphosphate) and the highest dry forage yield (3410 kg/ha) and the highest mother and replacement corm per clump were obtained in sheep manure (40 t/ha). however, the highest corm weight per clump (119 g), average corm diameter (1.6 cm) and average number of bud per corm (6.5) were observed in 300 kg/ha urea, the maximum average weight of corm (2.4 g) and total number of bud per clump (410) were obtained in 100 kg/ha urea and 30 t/ha sheep manure, respectively. most of growth indices and yield of saffron were improved by increasing in levels of sheep manure and chemical fertilizer but most of that charachteristics had a decreasing trend by increasing in levels of cow and hen manure. generally, the highest amounts of most studied indices were obtained in chemical fertilizer and sheep manure and the lowest amounts of those studied indices were observed in hen manure.