Saffron Agronomy and Technology

Abstract To evaluate the allelopathic and antifungal effects of saffron (Crocus sativus L.) leaf and corm extracts on the germination and early growth of Peganum harmala and on the mycelial growth of Fusarium nygamai, three independent factorial experiments were conducted using a completely randomized design with three replications. The experiments were carried out in 2021 at the Seed Research Laboratory, Research Greenhouse, and Plant Disease Laboratory, Faculty of Agriculture, University of Birjand. In the first experiment (laboratory bioassay), treatments consisted of two saffron plant organs (leaf and corm) and seven extract concentrations (0, 0.0625, 0.125, 0.25, 0.5, 1, and 2% w/v) applied to assess inhibitory effects on the germination parameters of wild rue seeds. The second experiment (greenhouse pot study) employed identical treatments to evaluate seedling emergence and growth characteristics. In the third experiment, the same treatment structure was used to investigate the inhibitory effects of extracts on the mycelial growth of F. nygamai. The results of the interaction of treatments in laboratory conditions showed that the lowest germination percentage, mean germination time and allometric coefficient were obtained from the 2% concentration of corm extract. The lowest length of radicle and shoot, dry weight of shoot and root were obtained from the 2% concentration of corm extract. In greenhouse conditions, the 2% corm extract and the 1 and 2% leaf extract treatments resulted in the lowest germination percentage, prolonged mean germination time, reduced germination rate coefficient, and lowest allometric coefficient. Furthermore, the minimum shoot length, root length, shoot dry weight, and root fresh weight were obtained from the same treatments. The results of the antifungal test showed that the lowest diameter of the fungal colony on the third and sixth day was obtained from the 2% concentration of extract, which had no statistically significant difference with the 1% concentration of extract. On the ninth day, the lowest colony diameter was obtained from a concentration of 2% corm extract, which had no statistically significant difference with concentrations of 1 and 2% leaf extract. Finally, the results of these experiments showed that the effect of inhibiting germination and growth of wild rue in laboratory conditions was greater in saffron corm extract and in greenhouse conditions in leaf extract, and the antifungal effect of leaf extract was greater. Therefore, considering the results of this study and conducting more research in the field of fungicidal and allotoxic effects of saffron organ extracts, it is possible to produce natural fungicides and herbicides.

Abstract Although saffron (Crocus sativus L.), as one of the most important medicinal-spice species with low water requirement and high economic value, is not tolerant to salinity, evidences show that it is not highly sensitive to salinity either; however, information about saffron response to salinity at the field scale is very limited. The present study aimed to investigate the effect of irrigation with different levels of electrical conductivity (2, 5, 8, and 11 dS m-1) and different amounts of nitrogen (0, 25, 50, and 100 kg ha-1) on saffron stigma yield and changes in soil salinity. The results showed that stigma yield decreased significantly with increasing salinity in both years, especially in the second year; so that in the second year, no plants grew in the 11 dS m-1 treatment. The reduction in yield due to the highest salinity level in the first and second years was 75.3% and 80.9%, respectively. Only in the second year did nitrogen have a significant effect on stigma yield; the highest yield was obtained at salinities of 2 and 5 dS m-1 from the 50 kg N ha-1 treatment and at salinity of 8 dS m-1 from the 25 kg N ha-1 treatment. The effect of saline irrigation on the electrical conductivity of the saturated soil extract (ECe) was observed from 50 days after planting (DAP), and over time up to 150 DAP, water salinity treatments (except 2 dS m-1) led to an increase in ECe at two depths of 0 to 30 and 30 to 60 cm. At this time, the average ECe of the two depths in irrigation water treatments with salinities of 2, 5, 8 and 11 dS m-1 was equal to 0.3, 1.8, 10.9 and 13.9 dS m-1, respectively. In the second year, the treatments maintained the differences made in the first year relatively evenly throughout the growing season. Given the good regression relationship between the EM38 and ECe readings, the apparent salinity (ECa) could be estimated using the EM38. The differences between ECa in nitrogen and salinity treatments were very pronounced, with the highest ECa being obtained from the 11 dS m-1 treatment. Overall, the results showed that semi-saline water could be used for saffron cultivation with a slight yield reduction, however, irrigation and nutrition management should be carefully observed. In low salinity, 50 kg N ha-1 and in medium salinity, 25 kg N ha-1 is suitable for improving saffron yield. By observing the appropriate leaching fraction for saline conditions and the stability of soil salinity, it is expected that soil salinity at the end of the growing season will be 1.4 times the average of irrigation water, and soil salinity at the end of the saffron growing season will be between 0.94 and 1.44 times that at the beginning of the season.

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  The study was conducted in order to compare the yield of onion, flower, stigma, and some agricultural characteristics of the saffron plant as an alternative crop. This study was carried out as a complete randomized block design in 3 replications in three regions of Aliabad, Naqdeh, Qajlu, Miandoab, and Balanj, Urmia, and in each region, four ecotypes of Korqand, Hoz-sarakh, Jarf, and Shahnabad were cultivated evaluated for 5 years from September 2016. From the second year to the fifth year, flowers were harvested, and the agricultural traits of the ecotypes, including the number of flowers, fresh weight of flowers, dry weight of petals, stamens, and production stigma yield, were measured or recorded. In the sixth year, the yield and the number of corms produced were measured. The results showed that there was a significant difference between the ecotypes. The interaction effect of place in ecotype, year in ecotype, and year in place was also statistically significant. The highest yields of stigmas and flowers were produced in Aliabad Naqdeh region, and among the four saffron ecotypes cultivated, Korqand and Jarf ecotypes had the highest number and weight of flowers, the highest weight of stigmas, the number of corms and the weight of corms in all three regions, respectively. According to the results, the ecotypes of Korqand and Jarf ecotypes are recommended for cultivation in the central and southern parts of West Azerbaijan province.

Abstract Saffron is one of the most important crops and medicinal plants in Iran and plays an important role in non-oil exports of the country. Although Iran has the largest area under cultivation of saffron, its yield is low compared with global production. The main objective of this study is to investigate the yield of flowers and quantitative characteristics of daughter corms under the effects of application of plant growth regulators priming and two different corm sizes. A factorial experiment arrangement in RCBD with four replications was conducted, under the terms of pot at the College of Aburaihan-University of Tehran, Iran during 2015. Small (3-5g) and large (8-10g) mother corm sizes were hormonal priming by gibberelic acid (GA₃), cytokinin (BA), auxin (IBA) with 250 ppm concentration and before cultivation. The start of flowering, number and flowers yield, fresh weight of flower, fresh and dry weight of stigma, number and weight of daughter corms per mother corms were measured. The results showed that in all traits except the start of flowering large corms weighing of 8 to 10 g were cultivated in comparison with small corms and this was significant at the 1% level. Application of cytokinins hormone in comparison with control for all traits except the start of flowering and weight of daughter corms showed a significant difference at 1%. Application of gibberellic acid hormone treatment also accelerated flowering. In addition, it increased the weight of daughter corms by 56% in large mother corms compared to control and this had a significant difference from control at 1%. Auxin (IBA) in the number of flowers had no significant difference with control and also in other traits, although IBA was better than control, with both BA and GA₃ treatments had a significant difference. The results indicated that the use of large mother corms with hormonal priming with BA and GA₃ will improve flower and corm yield in the first year.

Abstract Saffron is one of the most valuable agricultural products in the global market. Iran has the largest area under cultivation and the highest production of this crop. However, Iran's share of the value added of saffron in the global market is unacceptable and declining, which indicates the many challenges facing this industry. The purpose of this research is to explain the hidden structures of the challenges of production, processing, and marketing, and to rank the most important challenges of the saffron industry in Torbat Heydarieh, Iran, which is the world's saffron center. The necessary data were collected in 2023 using a convenience sample of 108 questionnaires. The challenges were ranked using Friedman's test and the weight coefficients obtained from factor analysis. Principal component analysis was used to identify the hidden patterns in the challenges of production, processing, and market (domestic and international) of the saffron industry in Torbat-e Heydarieh. The challenges were then ranked using Friedman's test and the weight coefficients obtained from factor analysis. The study found that the most important challenge facing the saffron industry in the production sector is climate change, in the processing sector is the need for high working capital, in the international markets is strict customs regulations, and in the domestic markets is the lack of cooperation of the rural cooperative to purchase the product. Factor analysis revealed that the most important hidden components in the production sector are "production instability" and "low production efficiency"; in the processing sector, "technical and infrastructural challenges" and "financial challenges"; in the domestic market, "lack of development of the domestic competitive market" and "weak domestic market institutions"; and in the international market, "lack of access to foreign markets" and "poor saffron quality in foreign markets."

Abstract Saffron is one of the most popular traditional herbs and the most expensive spice globally. Global production of saffron is estimated at 418 tons per year on 121,338 hectares. This spice is beneficial for human health because it has three main bioactive compounds: crocin, picrocrocin, and safranal. In recent years, in addition to numerous studies on various medicinal effects due to the decrease in its production, research on factors affecting saffron production has increased. Consequently, conducting a bibliometric analysis of publications can provide insights into current areas of interest and potential trends for future research. The purpose of this research is to reveal the research topics of the saffron field in the WoS database during the period from 2000 to 2023, which was done with the benefit of scientometric techniques. The current research community includes 3936 articles. Data analysis and drawing of the intellectual structure of knowledge was also done using R Biblioshiny and VOSviewer software. Acta Horticulturae was the most popular journal for saffron research, with 216 published articles, while the American Chemical Society's Chemistry journal was the most cited. The scientometric analysis identified the most productive countries, and Iran was at the top with 1015 single-country publications (SCP), 155 multi-country publications (MCP) and the highest frequency of 0.297. According to the current research, the research topics related to saffron that have recently become more advanced and can be used as a basis for the authors' research include antioxidants, double-blind testing (medical), oxidative stress, inflammation, type 2 diabetes, major depressive disorder, alpha-amylase, are fatty acids. This study highlights the link between collaborations and scientific developments and trends in scientific collaboration and serves as a model to show emerging research directions in the field of saffron.

Abstract The main component responsible for color in saffron is crocin with the chemical formula of C₄₄H₆₄O₂₄. Crocin is one of several carotenoids in nature that is soluble in water. This solubility is one of the reasons for its widespread usage as a colorant in food and medicine compared to other carotenoids. The coloring strength of saffron is one of the major factors that determine the quality of the saffron stigma. It will be evaluated with measuring of crocin. Microextraction is the newest and easiest method that can be successfully applied for the preconcentration and separation of crocin in saffron samples. The advantages of this method are faster, cheaper and easier analysis by UV-Vis spectrophotometry in measurement of crocin compared to the chromatographic analysis methods. The studies showed that the type and volume of disperser and extractant solvent have a significant effect on the efficiency of crocin extraction. In this work, acetone as the disperser solvent and dichlorometane as the extractant solvent were found to be suitable combinations. Under the optimal conditions, the calibration curve was linear in the range of 0.15-0.00001 μg mL^-1 and the limit of detection (LOD) was calculated based on 3 Sb/m (where, Sb and m are the standard deviation of the blank and slop ratio of the calibration curve respectively) was 0.000008 μg mL^-1. The procedure was applied to saffron samples and the good recovery percent for the saffron samples was obtained.

Abstract Saffron is the most expensive agricultural product in the world and Iran is the largest saffron producer in the world. Saffron contamination in different stages of the production process, in addition to quality loss leads to reducing credit in the global market and exporting. Therefore, it is necessary to select an appropriate method for inactivation the microbial flora of saffron. Among the common methods that used to inactivation the microorganisms, cold plasma is due to the potential benefits such as non-toxic nature, low operational costs, and a significant reduction in water consumption during decontamination, and the possibility of its use for a variety of food products has attracted much attention. Plasma is a state of ionizing gas, including ions, electrons, ultraviolet rays, and reactive species such as radicals, atoms and molecules that can ignite, which can inactivate microorganisms. in this research, cold plasma was produced using two types of gas including nitrogen and air, and the effect of plasma radiation at 0, 3, 6, 9 and 12 minutes on the chemical and microbial (Escherichia coli, Enterococcus faecalis, Mold and Yeast) properties of saffron were investigated. The results of this study showed that germicidal effect of nitrogen plasma was lower than air plasma and the plasma exposure time had a significant effect on reduction of microbial load and by increasing the time of plasma exposure, the inactivation of microorganisms increased. The maximum microbial reduction was observed in 12 minutes. Maximum reduction in microbial load was observed at 12 minutes and 18 kilovolt voltage, which reduced the population of Escherichia coli, Enterococcus faecalis, mold and yeast by 2/69, 2/48, 1/95 log cycle respectively, However, with increasing radiation time, the amount of crocin, picocrocin and safranal decreased (p˂0.05). Reduction of crocin, safranal and picocrocin in 12 minutes was 6/01, 4/04, 5/44%, respectively.

Abstract Saffron (Crocus sativus L.) is a perennial plant which grows basically in arid and semi-arid regions of Iran. Despite saffron’s adaptation to these regions, the assessment of changes in cultivation area over the last 30 years reveals that cultivation of this crop has sharply increased. According to the available statistics, there are 21 provinces where saffron is cultivated on about 84,000 hectares of land. Nonetheless, saffron yield per unit area has aggressively fallen from 5.1 kg ha^-1 in 1982 to 3.2 kg ha^-1 in 2015. Saffron yield loss can be caused by several factors, such as mismanagement in agriculture section, economics and post-harvest processing as well as the recent droughts. Lack of attention to these factors could lead to further decline in saffron yield in the future. The saffron yield loss over the last 30 years is an alert for saffron-related institutions such as the universities, research centers and Agricultural Research, Education and Extension Organization (AREEO) to pay more attention to this crop and prepare more comprehensive programs. In developing these programs, the importance of government policies for planning and approving enough budget is to be highlighted. In this review, first we focus on the reasons for saffron yield loss during the last 30 years and then we try to provide some solutions in relation to these reasons.