Saffron Agronomy and Technology

Abstract One of the methods to improve production and control flowering in plants is the use of growth regulators such as gibberellic acid. In order to investigate the effect corm priming time of saffron with gibberellic acid (GA3), a factorial experiment was conducted in a randomized complete block design with three replications at the Agricultural Research Station,University of Tehran in 2023. Two planting times (late June, late September) and four levels of gibberellic acid (0, 100, 200, and 400 ppm) were considered as treatments in the form of corm priming. The evaluated traits were the number of buds, time to germination, number of flowers, time to flowering, bud-to-flower conversion ratio, dry weight of stigma, and quality traits of saffron stigma. The results showed that priming saffron corms with 100 ppm gibberellic acid in late June significantly (α=1%) increased the number of flowers, bud-to-flower conversion ratio, fresh and dry weight of stigma, crocin and safranal. However, corm priming in late September with 200 ppm gibberellic acid resulted in a significant increase (α=1%) in the number of buds, number of flowers, stigma length, fresh and dry weight of stigma, and a significant decrease (α=1%) in the time to flowering onset and germination, although in some traits they were in the same statistical group as the 400 ppm level. Overall, the results of this experiment showed that first, corm priming in late June with low levels of gibberellic acid is better, but, corm priming in late September with higher levels is beneficial. Secondly, corms priming in late June and at a level of 100 ppm of the hormone can increase the amount of crocin and safranal and yield traits, while priming corms in late September can reduce the time to flowering and time to germination And will improve flower and corm yield in the first year.

Abstract Salicylic acid as a plant hormone plays an important role in regulating growth and physiological processes in plant. In order to study the effects of salicylic acid hormone and mother corm weight on saffron flowering properties, an experiment was conducted as factorial based on a randomized complete block design with three replications at the saffron research field of College of Aburaihan, University of Tehran during 2016-2017. The first factor consist of salicylic acid in three levels (Normal, priming with 1 and 2 mM concentrations (and second factor was weight of corm in two level that consist of small corm (3-5 gr) and large corm (8-10 gr). The results showed that the effect of corm weight on fresh weight of flower, Length of flower, fresh weight of stigma, length of stigma, fresh weight of pistil, length of pistil and qualitative characteristics of stigma were significant. The amount of these traits was higher in terms of the use of large mother’s corms. The effect of corm weight on dry weight of stigma was not significant. Interaction between salicylic acid and corm weight on all traits was not significant but the results of mean comparisons showed that the highest amount of fresh weight of flower (99.5 kg/ha), dry weight of stigma (1.45 kg/ha) and lowest days to emergence was 47 days after planting that related to salicylic acid in 2 mM. More amount of picrocrocin as a saffron flavor was related to salicylic acid in 1 mM. Crocin percentage in the priming treatment with 2 mM salicylic acid was higher than the other two levels; amount of safranal was high at 1mM. Totally, results of this experiment indicated that planting large mother’s corms with salicylic acid led to improvement of some quantitative and qualitative characteristics of saffron stigma.