THE EFFECTS OF CHEMICAL AND ORGANIC FERTILIZERS ON SAFFRON FLOWERING

The effects of chemical and organic fertilizers on saffron (Crocus sativus) were studied in a field experiment using a complete randomized block design with three replications at Ferdowsi university of Mashhad. Fertilizers applied were N, P, K, NP, NK, PK, NPK, cow, sheep and chicken manures. The amounts of chemical fertilizer applied were 50, 30, 30, 48, 48, 36 and 66 kg/ha for N, P, K, NP, NK, PK, NPK and 12, 8, 4 t/ha for cow, sheep and chicken manures, respectively. The results indicated that the number and weight of flowers and the stigma dry weight were affected by the type of fertilizer (p<0.01). The highest number of flowers was obtained with cow manure and the lowest with N, NK and PK fertilizers. The highest stigma dry weight was obtained with cow manure (0.093 g/m²) and the lowest with PK treatments (0.035 g/m²). The highest flower dry weight was obtained with NPK and the lowest with N and PK application (0.92 and 0.33 g/m²), respectively. Stigma dry weight has a stronger correlation with the number of flowers compared to flower dry weight.