Saffron (Crocus sativus L.) yield as affected by different fertilizing systems

Saffron (Crocus sativus L.) quantitative and qualitative yield was assessed in a factorial experiment based on randomized complete block design with three replications. The factors included NPK fertilizers at three levels (0، 50 and 100 percent of the recommended amount of fertilizer) and non-chemical fertilizers in four levels (no fertilizer، vermicompost، bio fertilizers containing Pseudomonas and Bacillus، and integrated application of vermicompost and bio fertilizers). Results showed that the interaction effect of chemical and non-chemical fertilizers was significant on all parameters and fertilization increased the quality and quantity yield of saffron compared to control. Integrated application of 50% of the amounts of chemical fertilizers، vermicompost and bacteria was the superior treatment to increase stigma dry weight، stigma yield، crocin percentage، picrocrocin percentage and safranal percentage by 2. 03، 4. 65، 0. 83، 1. 10 and 1. 46 fold، respectively in comparison with control. Although the effectiveness of integrated application of bacteria with 0% and 100% chemical fertilizers on crocin content، pure vermicompost and integrated application of bacteria with 50% and 100% chemical fertilizers on picrocrocin content and pure bacteria on safranal content were more than those of integrated application of vermicompost، bio and 50% chemical fertilizer، the greatest impacts of recent treatment on flower yield، stigma yield and stigma ingredients led to introduce it as the superior treatment. The effectiveness of this treatment compared to 0%، 50% and 100% of chemical fertilizer application on dry stigma was 50. 95%، 20. 48% and 12. 86%، respectively.