In order to investigate the effects of growth regulators components on quantitative and qualitative yield of saffron, a completely randomized design with three replications was conducted at field level. Growth regulators treatments were included as 50, 150 and 300 ppm gibberellic acid (GA3) and naphthalene acetic acid (NAA) compounds. Saffron corms weighing 8 to 10 grams were immersed in solutions of GA3 and NAA and then were planted in 1×1 meter plots with 15 cm within row and 20 cm between row spacing. At the end of the growing season (end of June), crop traits such as total number and weight of the produced corms and the number and weight of produced corms in weighing groups of less than 4 grams, 4 to 8 grams, and more than 8 grams were measured by harvesting one third of the cultivated corms in each plot. At the flowering time of the remaining corms of each plot (November), weight and number of flower, fresh and dry weight of stigma, and the amount of active ingredients including crocin, picrocrocin and safranal were measured. The results showed that all studied traits were affected by growth regulator compounds and indicated significant compared with control treatment at 1% and 5% probability levels. GA3 improved biological yield and corm weight, in addition it could increase the quality of stigma compared to the control treatment. 150 ppm GA3 increased the weight of corms by 16.25% and the number of flower per plot by 34.99% compared to the control treatment. Also, 300 ppm GA3 increased the dry stigma yield by 37.5% compared to the control treatment. NAA did not affect yield production significantly and at high concentrations, prevented the growth of corms and flower production. According to this study results, it seems that concentrations higher than 150 ppm GA3 can increase the yield of saffron, and are able to play an important role in enhancement of saffron farms productivity.

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