Saffron Agronomy and Technology

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 Drought stress is one of the most important abiotic stresses that reduces crop production more than any other stress. Micronutrients such as iron and zinc can improve drought stress tolerance in saffron. For this purpose, the present study was conducted in the growth chamber of the College of Science, University of Tehran, in order to investigate the effect of iron and zinc on vegetative characteristics and resistance traits of saffron plant under water stress conditions as a factorial based on a completely randomized design. In this experiment, iron and zinc were investigated at three levels of half concentration of Hoagland, full concentration and twice the concentration of Hoagland solution and at four levels of dryness of 0, 5, 10 and 15% polyethylene glycol 6000 (PEG). The results showed that drought stress reduced fresh and dry root weight (1.36 g and 0.12 g in PEG 15%), root length (2.67 cm in PEG 15%), leaf and root protein content (0.05 and 0.04 mg/g FW in PEG 15%) and oxidizing enzymes (such as root peroxidase (1.04 IU/g protein in PEG10% and in PEG15% (1.09 IU/mg protein), leaf polyphenol oxidase (in PEG5% (0.14, 0.15 IU/mg protein in PEG10% and 0.14 IU/mg protein in PEG15%), leaf catalase (0.63 in PEG5%, 0.59 IU/mg protein in PEG10% and 0.34 IU/mg protein in PEG15%) and root catalase (0.25 IU/mg proein in PEG10% and 0.18 IU/mg protein in PEG15%). The use of iron and zinc in full concentrations and twice the concentration of Hoagland solution improved some qualitative and biochemical properties such as total chlorophyll (full concentration of zinc in PEG15% as much as 4.48 mg/g FW), chlorophyll a (twice the concentration of zinc in PEG5% as much as 2.96 mg/g FW), chlorophyll b (zinc at full concentration in PEG15% as much as 5.04 mg/g w/w) Wet), carotenoids (zinc twice the concentration in PEG10% by 0.73 μg/mg protein), leaf flavonoids (iron twice the concentration of PEG5% by 0.18 μg/g FW), zinc root flavonoid twice the concentration in PEG0 by 0.15 μg/g FW), leaf flavonoids (iron twice the concentration in PEG15% by 0.05 μg/g FW) and flavonols (Leaf flavonols (twice the concentration of iron in PEG15% by 0.05 μg/g FW) and root flavonols (twice the concentration of iron in PEG5% by 0.21 μg/g FW). Finally, treatment with iron and zinc improved the status of some of the measured parameters under drought stress conditions. The use of these concentrations of iron and zinc is recommended to reduce the negative effects of drought in saffron.

Abstract Considering the economic, political, social, cultural and environmental value of saffron (Crocus sativus L.) and however the production of more stability and yield through proper crop management, it seems to use new technologies in production and increasing of the yeild of saffron is inevitable, Therefore, the aim of this study was to investigate the effect of substrate type and depth of coriander cultivation on some morphophysiological characteristics of saffron in the hydroponic system. This experiment was conducted in the form of a completely randomized factorial design with four replications. Experimental treatments included three types of culture medium (cocopeat, soil and soil compost) and two depths of coriander (5 and 10 cm). Based on the results of this study, the type of cultivation bed had a significant effect on all traits except stigma dry weight and picrocrocin, so that the amount of Total chlorophyll (1.82, 1.06 and 0.75) and the amount of safranal of saffron stigma (19.1, 18.9 and 17) The order was higher in sawdust, cocopeat and sawdust compost beds, respectively. The interaction effect of cultivation bed type and cultivation depth on number of flowers, dry weight of flowers, stigma dry weight and crocin content was significant. The mean of highest number of flowers (29.5) and dry weight of saffron flowers (3.32 gr) were observed in sawdust compost bed and cultivation depth of 10 cm. The dry weight of saffron stigma at both cultivation depth in sawdust compost treatment was significantly higher than cocopeat and sawdust substrates. The highest amount of crocin (the value of 230) was observed in sawdust bed and planting depth of 10 cm. In general, due to the positive effect of sawdust compost in improving the yield and quality of saffron, the use of sawdust compost and cultivation depth of 10 cm for saffron production in the hydroponic system is recommended.

Abstract Given that saffron is a bulbous and perennial plant, various environmental factors can significantly influence its growth and development. To investigate the corm and flower characteristics of saffron under the influence of different biofertilizers and irrigation regimes, an experiment was conducted over two agricultural years (2021-2022 and 2022-2023) in the agricultural fields of Ziar city, a suburb of Isfahan. The experiment was designed as split plots in a randomized complete block design with three replications. In this experiment, deficit irrigation at three levels (50%, 75%, and 100%) was considered the main factor, while nitrogen-fixing free-living bacteria (B-N), potassium-solubilizing bacteria (B-K), phosphate-solubilizing bacteria (B-P), their combinations, and a control without fertilizer were considered the sub-factor at eight levels. The results demonstrated that the highest number of corms (415 m-2), corm weight (2360 g. m-2), corm weight without tunics (2304 g. m-2), number of corms weighing 0-4 grams (244 m-2), number of corms weighing 4-8 grams (135 m-2), number of corms weighing 8-12 grams (55.3 m-2), and number of corms weighing more than 12 grams (64.2 m-2) were obtained under the 100% irrigation requirement treatment with the combined NPK biofertilizer. Moreover, the highest dry stigma weight (0.492 g. m-2) and dry style weight (0.122 g. m-2) were achieved in the 100% irrigation requirement treatment with the combined NPK biofertilizer. Overall, the application of biofertilizers improved corm and flower performance characteristics under all three levels of drought stress. However, the positive effects of biofertilizers were more pronounced under stress conditions. Therefore, considering the ongoing water scarcity crisis in the country and the beneficial effects of biofertilizers, it is possible to achieve optimal yields with reduced water consumption.

Abstract The saffron bulb mite (Rhizoglyphus robini Claparède) is considered a serious threat in saffron cultivation areas in Iran. This soil-borne mite reduces the growth and is a cause of the yellowness of saffron plants and eventually destroys the corms. Due to the significance of this strategic product and its medicinal and export aspects, it is impossible to register any synthetic chemical compounds against pests and diseases of this plant in the country. Therefore, finding non-chemical and based on natural substances methods for the control of this pest is necessary. In this research the use of mite-pathogenic fungi is considered a promising approach for controlling this pest. To isolate and identify these fungi, soil samples were collected from saffron farms in 32 regions of Torbat-Heydarieh County in Khorasan Razavi province in 2022 and 2023. Overall, 55 fungal isolates related to eight genera were obtained and among them, 26 isolates could colonize the mites. The potent isolates that killed mites and caused at least 50 percent mortality after ten days were compared statistically. The results showed that on the 10th day, the effect of Metarhizium sp. isolate M-Kh and Cordyceps sp. isolate Co-TZ on mite mortality was 100 percent which was higher than other fungi, but, their difference with some isolates belonged to Beauveria sp. was insignificant (P<0.05). The mite colonization percentage of M-Kh isolate was 100 percent and significantly higher than other fungi (P<0.05). Cladosporium sp., Aspergillus spp., Penicillium spp., Fusarium spp., and Mucor spp. also caused the death of mites, but their effect was insignificant. Based on available information, this is the first report of the pathogenicity of the mentioned fungal genes against the saffron bulb mite in Iran. According to the results, these selected fungi can be used as biological control agents to protect saffron corms against mites.

Abstract Saffron corm rot caused by the bacterium Burkholderia gladioli pv. gladioli (Bgg), is an important disease affecting saffron cultivation. This study aimed to evaluate the effect of different doses of sodium bicarbonate and three copper-based compounds (copper oxychloride, Bordeaux and Nordox) on the population of Bgg isolates, in vitro. Additionally, the sensitivity of the Bgg isolates to 21 antibiotics was investigated. Two weeks after inoculation, the symptoms of the disease appeared as dry rot and brown lesions around the inoculated area. Varying degrees of virulence were observed among the Bgg isolates, with the Bg16 inducing the most severe symptoms. The Minimum inhibitory concentrations (MICs) were determined as copper oxychloride 3.5/1000, Bordeaux and sodium bicarbonate 12%, and Nordox 1.5/1000. The Bgg isolates were sensitive to nine antibiotics. The largest inhibitory zone diameters observed around trimethoprim sulfamethoxazole, nalidixic acid, gentamicin, and amikacin discs. One week after cultivation, the copper compounds decreased the bacterial population compared to the control, but no significant difference was observed between them in the second week. The most effective treatments in reducing the Bgg population were copper oxychloride at 2/1000 and 3/1000, Bordeaux at 8% and 10%, and Nordox at 1/1000 and 1.5/1000. The efficacy of the identified effective treatments will be further evaluated under field conditions.