نشریه پژوهش های زعفران
سال دهم شماره 2 (پاییز و زمستان 1401)

Amino acids are organic fertilizers. Adding these organic fertilizers to the soil improves the condition of microorganisms in the soil, which their activity facilitates the absorption of some nutrients and ultimately increases the growth and performance of the plant. To investigate the effect of amino acid and mother corm weight on qualitative parameters in petals and stigmas of saffron (Crocus sativus L.), an experiment was conducted at the Research Field of College of Agricultural, University of Birjand, in 2017. 

The experimental factors included amino acid (0, 2, and 4 L.ha-1) and corm weight [0.1-4 (small), 4.1-8 (medium), and 8.1-12 g (large-sized)] which were tested in an RCBD with three replications. After the land preparation operations including initial plowing, disk, and land leveling, plots of 2 × 2 meters were created. Irrigation was done by siphoning. The saffron corms were planted in grooves with a depth of 20 cm, the distance between the rows was 20 cm, and the distance between the corms was 10 cm. The amino acid was consumed before planting by submerging the corms and with the first irrigation when the plots were flooded uniformly. Harvesting of saffron flowers was done daily for about three weeks in the first hours of the morning, taking into account the marginal effect of the remaining surface of the plots. After weighing the flower yield in each plot, the different parts of the flower (petal and stigma) were dried in an electric oven at 45 °C for 24 hours and then used to measure the quality indicators. 

The use of amino acids had a significant effect on the carotenoid content and anthocyanin of petals and stigma crocin. The highest amounts of carotenoid content (0.95 mg.g-1 FW), anthocyanin (26.28 mg.100g-1 DW), and crocin (270.4% Absorbance of 1% aqueous saffron extract at 440 nm) were obtained when amino acid was used at the rate of 4 L.ha-1. However, no significant difference was found between the two levels of amino acid in terms of all the mentioned parameters. The lowest values of carotenoid (0.71 mg.g-1FW) anthocyanin (24.23 mg.100g-1DW), and crocin (230.5) were obtained from the control treatment. Mother corm weight also exerted a significant effect on picrocrocin content. The lowest content of picrocrocin was obtained in the amount of 100.7 (Absorbance of 1% aqueous saffron extract at 257 nm) of small-sized mother corms (0.1- 0.4 g) and the highest of 108.5 of large-sized mother corms (8.1-12 g). The interaction of these two factors (amino acid and mother corm weight) had also a significant effect on the safranal of stigma, and antioxidant activity of saffron petals. The highest content of safranal (36.82, Absorbance of 1% aqueous saffron extract at 330 nm), and antioxidant (31.26%) were obtained from corm 8.1-12 g and 2 or 4 L.ha-1 of amino acid. 

The results of this research showed that the planting of larger mother corms and the use of amino acids can be useful in improving the quality characteristics of petals and effective substances of saffron stigma. Since no statistically significant difference was observed between the consumption levels of two and four liters per hectare of amino acids in most of the studied traits, to reduce production costs, two liters per hectare of organic input of amino acids can be suggested. This amount can vary depending on the characteristics of the soil in each region. The results of this study indicated the beneficial effects of amino acid on improving biochemical traits and effective ingredients which is appropriate for the organic production of saffron.

Iran is currently considered the largest producer of Saffron in the world and has the largest area under cultivation of this product. Saffron is cultivated in environments with very different soil characteristics. Saffron can be cultivated both in areas with low rainfall and in areas such as Greece with rainfall greater than 500 mm.  Location of the Sampling Points: The present research was carried out during the time frame of 2015–2017 in two regions of Ghaen and Vamanan located in South Khorasan and Golestan Provinces, respectively. Sampling was done from 30 Saffron farms with three replications, i.e., 90 profiles were sampled from 3 to 5 years old farms in each of the studied areas in Ghaen and Vamanan to measure the soil texture. Saffron flowers were collected and the fresh weight was measured and then according to the area of the field, it was reported as kilograms per hectare. In order to explore the relation between the climatic parameters and the yield of Saffron in the regions under investigation, the climatic indicators of 5-year data (1390-1395) from the station of Vamanan and Ghaen were collected from the climatology center of Khorasan province and the climatic organization of Golestan province.  Based on the results of the estimated regression model listed in table (4), clay, silt and the ratio of silt to sand of the investigated fields had a significant effect on the yield of Saffron in Ghaen at a significant level of less than 10%. In addition, the interaction effect of silt and sand (SCIN) on changes in Saffron yield was significant at the level of about 12%. Based on the estimation results, the effect of soil clay on the yield of Saffron was positive and significant. In such a way that by increasing this factor by one unit, it was expected that 0.19 kg would be added to the yield of Saffron. The effect of silt on changes in Saffron yield in Ghaen was positive and about 0.1 kg. As in Ghaen, quantitative relationship between Saffron yield and soil texture of investigated farms in Vamanan was also investigated using regression analysis. Another finding of the present research was the significance of the interaction between silt and clay. This effect was negative and indicated that these two factors reduced each other's effect on Saffron yield. Also, the model estimation results showed that the interaction effect of soil silt and sand was also significant and relatively significant in changes in Saffron yield. The small amount of this effect was about 0.012. Another result of estimating the regression model was the negative and significant effect of the ratio of soil silt and sand on Saffron yield. In such a way that by increasing the ratio of these two soil characteristics by one unit, Saffron yield was expected to decrease to a significant amount of 3.2 kg.hectare. Therefore, the balanced ratio of soil silt and sand will have a significant effect on the yield of Saffron. Some researchers believe that Saffron grows better in light soils rich in organic matter, while others stated that the best soil texture for planting Saffron is clay texture which is in contrary to the results of this research.The regression model showed that other conditions being constant, the yield of Saffron would be decreased by 0.125 kg per hectare with each increase in the number of frost days. The research results also indicated that if frost occurs during flowering, it will have a negative effect on the yield of the product. Also, rain during summer dormancy is harmful for Saffron.  In the current research, the influence of the effective climatic indicators on the yield of Saffron in the two regions of Vamanan and Ghaen has been investigated. The results also showed that the yield per hectare of Saffron in Ghaen and Vamanan climates was affected by the number of frost days. On the other hand, the findings showed that the soil texture had an effect on all the growth characteristics of the Saffron plant, so that the use of soil with a lighter texture created optimal conditions for the growth of Saffron stem and ultimately increased the yield of Saffron flowers and stigmas.

Potassium is the most abundant inorganic cation in plant tissues that plays a major role in physiological processes, especially in growth and metabolism. Although there is substantial evidence about the effects of potassium fertilizer on increasing the qualitative and quantitative yield of plants, little is known about the effects of applied potassium on saffron and the improvement of the quality and yield of the saffron flower. The purpose of this study was to evaluate the effects of biological and chemical potassium fertilizer and corm weight on some physiological traits and yield of saffron (Crocus sativus L.).  An experiment was conducted as factorial based on a randomized complete block design with three replications and eight treatments at the saffron research field of the College of Aburaihan, the University of Tehran during 2015-2016. Experimental treatments included two levels of potassium sulfate fertilizer (0 and 200 kg. ha-1) as the first factor, two levels of Potabarvar-2 biofertilizer (0 and 100 g. ha-1) as the second factor, and two corm weights including small (3-5 g) and big (8-10 g) were the third factors. Potabarvar-2 biological fertilizer used in the research has a set of the most effective potassium-releasing bacteria called Pseudomonas spp. Strain s19-1 and Pseudomonas spp. strain s14-3, which was inoculated with corms before cultivation. Potassium chemical fertilizer treatment of potassium sulfate type and in the amount of 200 kg per was used as pre-planting in the soil of the desired plots. The corms were planted at a distance of 10 cm on the row at a depth of 15 cm at the end of June. In order to increase the colonization of bacteria around the corm, irrigation was done after planting and then summer irrigation was done on the first of September, the appearance of the first flower was at the beginning of November and the end of flowering was in the middle of December. In this research, functional traits including the number of flowers, flower fresh weight, stigma dry weight, and physiological traits including petal anthocyanin, leaf soluble protein, and total leaf soluble carbohydrate were measured.  the results of this experiment indicated that the application of potassium, especially in the form of biofertilizer, had positive effects on improving flowering and increasing the number of flowers in both groups of saffron corms, especially small corms (3-5 grams). Also, the increase in the fresh weight of flowers was evident in the combined application of biological and chemical fertilizers, especially in large corms (8-10 grams). Stigma dry weight increase as an important component of saffron performance was affected by the application of chemical fertilizer, although biological fertilizer also caused a significant increase in this functional trait compared to the control. The application of potassium sulfate in combination with biological fertilizer had the greatest effect on increasing the concentration of total carbon hydrates, total leaf protein, and petal anthocyanin content. Therefore, in most of the measured traits, biofertilizer has positive effects, and to achieve the maximum flower yield and quality of saffron per unit area, biofertilizer alone (100 grams per hectare) or in combination with smaller amounts of potassium sulfate chemical fertilizer should be used. Applied fertilizers led to increasing in flower yield through an enhancement in the number of flowers, fresh weight of flower, and dry weight of stigma. Application of biological fertilizer alone led to an increase of three times the number of flowers in a big corm in comparison with a small corm and normal. There was a significant difference between normal treatment and application of both mixed fertilizers on the concentration of total carbohydrate and protein of the leaf and anthocyanin of the petal.  In summary, the results of this experiment indicated that the application of big corms by inoculating them with biological fertilizer of potassium, in addition to using smaller amounts of potassium sulfate chemical fertilizer before sowing would be affected the increase of flower yield and improve physiological traits effectively growth. Therefore, the use of biological potassium fertilizer led to a decrease of using of chemical fertilizers and will be promising for sustainable agriculture and reducing the environmental pollution.

Saffron (Crocus sativus L.) is a perennial plant and geophyte, triploid and belongs to the family of Iridaceae. One of the most important factors that has a great effect on the final performance is the size of corm. Therefore, in order to obtain large corms, it is very important to create suitable environmental and management conditions. Determining the appropriate planting depth is also one of the ways to improve the performance of saffron per unit area. The purpose of this research is to investigate different sizes of saffron corms and planting depth on the yield of daughter corms of different sizes, flower and dry stigma of saffron in the conditions of Sari plain.  The present study was conducted to investigate the effect of different weights of mother corms and different planting depths on corm production and saffron yield in a factorial experiment based on a randomized complete block design and in three replications in the research farm of Sari Agricultural Sciences and Natural Resources University during the growing season 2019-2020. The experimental treatments included three corm sizes: weight group; small 4±2 g, medium 10±2 g and large 15±2 g and two planting depths of 10 and 15 cm. The studied traits included: the number and yield of daughter corms, the number of buds, the number and yield of flowers and the yield of dry saffron stigma. Data analysis and graphs were done using SAS 9.0, Excel 2016 and Sigma Plot 12.0 software, respectively, and comparison of average data with the help of LSD test at 5% probability level.  The trend of temperature changes as well as the investigation of the phenological events of saffron in the study area showed that at the beginning of the growing season and in the middle of autumn, the emergence of leaves is observed along with the emergence of reproductive organs (fig.1); This factor is probably related to the temperature fluctuations at the beginning of the plant's growing season (Table 1), and on the other hand, due to the allocation of the stock of mother corms to the leaves, it ultimately reduces flowering and stigma yield. The results showed that the highest number of daughter tubers and the total yield of daughter corms with 485 corm/ m2 and 2435.3 g/m2, respectively, were related to the treatment of large mother corm; however, no significant difference was observed between these traits in two planting depths for large corm (Table 2). The lowest total yield of daughter corms related to the treatment of planting small mother corms at a depth of 10 cm was equal to 1488.7 corm/ m-2. The average weight of daughter corms produced in this experiment (between 4.72 and 5.37 g) was about twice more than the amount produced in dry areas (Moallem Banhangi et al. 2019, Moein Rad et al., 2018. Razavian et al. 2019, Sharifi et al. 2021 & Esmi et al. 2019).  According to the results obtained in this experiment and also taking into account the texture of the field soil under test, the depth of 15 cm is more suitable than the depth of 10 cm for the production of corm with the desired size. But there is a possibility that in areas and lands with heavier soil, especially in the conditions of Mazandaran plain, which has abundant rainfall and poor drainage in some areas, shallower planting (10 cm deep) is better than deeper planting. It created more favorable conditions for root growth. Because the shallow planting depth, while creating drainage and better exit of excess water from the environment around the root and stem, provides a better growing environment for the growth of this plant. Therefore, according to the mentioned cases and the climatic features of the Sari plain, for better productivity of agricultural land in autumn and winter, saffron cultivation should be done annually and with priority to produce high-quality seeds and use these seeds in saffron-rich areas or conditions Aviation can be considered.

Saffron (Crocus sativus L.) as the most expensive spice in the world, has a special situation among Iran's export products. In addition to Iran, this plant is cultivated in Spain, India, Italy and Greece. The purpose of saffron cultivation is to harvest its stigma and long style, which is transparent red in color and has a lot of medicinal and nutritional value. The performance of saffron is related to several factors such as soil, density, planting method, corm size, geographical location, atmospheric factors such as temperature fluctuations, especially during flowering time, rainfall, crop management and exploitation period. Therefore, in order to make saffron cultivation feasible, it is necessary to identify the susceptible areas in terms of climatic factors in the country in order to increase the production of saffron in the country. One of the ways to increase the yield of saffron is to increase its cultivated area by identifying areas prone to cultivation and production of this valuable medicinal plant for domestic use, export, and also to extract the important compounds in its essential oil. Therefore, this study was conducted in order to investigate the different areas prone to saffron cultivation in Lorestan province and the effect of the weather conditions of each city on the important compounds in saffron essential oil.  This study was performed to investigate the compatibility of saffron and also changes in its essential oil components in different parts of Lorestan province. The experiment was conducted in the crop year 2020-21 as a randomized complete block design with three replications. In this study, 12 different cities of Lorestan province including Khorramabad, Boroujerd, Doroud, Kuhdasht, Azna, Aligudarz, Selseleh, Delfan, Aleshtar, Poldakhtar, Doreh Chegni and Romeshkan were considered as the experimental treatment.  The results showed that the effect of location treatment on fresh weight of flowers, fresh weight of stigmas, dry weight of stigmas, ratio of fresh weight of stigmas to fresh weight of flowers, maximum moisture and volatiles, safranal, crocin and picrocrocin was significant at 1% probability level. The results showed that out of 12 studied cities, the amount of saffron yield was economic only in 4 cities Boroujerd, Azna, Khorramabad and Selseleh. Among these four cities, the highest flower yield (79.66 g.m-2), fresh weight of stigma (6.77 g.m-2), dry weight of stigma (1.13 g.m-2) and stigma to flower ratio ( 0.085) was obtained in saffron cultivated in Azna city. The results also showed that the highest amount of safranal essential oil was obtained in saffron cultivated in Dorud city with a maximum absorption of 54. Also, the highest amount of crocin (maximum absorption 343.5) and picrocrocin (maximum absorption 144) were obtained. After Borujerd city, the amount of picrogrosin present in saffron essential oil cultivated in Elshatr (maximum absorption 126.5) and Selesh (maximum absorption 122) cities was more than other cities of Lorestan province, and the difference between them was statistically significant. Saffron essential oil cultivated in Kohdasht city (maximum absorption 80.5) had the lowest amount of picrocrocin. There was a difference between the saffron cultivated in different cities of Lorestan province in terms of the maximum amount of moisture and volatile substances, and it was found that the saffron cultivated in Borujerd city had the highest amount of moisture and volatile compounds at the rate of 0.094%, and after this city, Dure Chegeni had the highest amount of moisture and volatile compounds of 0.082%.  Investigating the feasibility of saffron cultivation in different parts of the country can increase its production in order to increase the country's exports. There have been different climatic areas in the country that have the ability to produce saffron, but currently they are unknown and the feasibility of cultivation should be done in them. In this study, it was found that saffron production was not possible in all the cities of Lorestan province, and the results showed that only 4 cities had the ability to produce saffron economically, and the highest production rate was in Azna city. Also, considering that the quality of saffron essential oil depends on its ingredients, based on these results, it was determined that the highest amount of safranal, crocin and picrocrocin was obtained in the saffron essential oil grown in cities with moderate climate such as Borujerd and Durud.

Saffron is one of the most valuable plant species in the world and it’s medicinal and spice applications have a long history. It is referred to as “red gold,” due to the high market price attributable to hand-harvesting and low production volumes. Saffron, dried stigmas of Crocus sativus L. (Iridaceae), was traditionally used as food spice worldwide to provide color, taste, and odour in several food recipes. The contents of these active compounds varies from region to region. About 150 volatile and non-volatile compounds and about 50 main compounds have been identified in saffron. Water-soluble carotenoids specifically characterize crocin which identify color of the saffron. Picrocrocin and glycoside safranal are responsible for bitterness while safranal provides odor and aroma properties. Saffron is one of the medicinal plants that have many uses in traditional medicine, including antispasmodics, helping natural digestion, soothing gums, anti-inflammation, anti-cancer, anti-anxiety, anti-depression perspiration enhancer, stomach tonic, sexual stimulant, expectorant, pain killer, anti-running nose and premature menstruation can be mentioned. 

articles about pharmacokinetics of saffron have been reviewed in this research. According to prevalent Neurodegenerative diseases, we selected eight illnesses in this paper including: Depression, Anxiety, Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Post-Traumatic Stress Disorder (PTSD), Schizophrenia, Epilepsy, Stroke. Then, approximately all recent researches related to these diseases has been reviewed. 

Saffron has the ability to scavenge free radicals because of its main constituents including carotenoids, safranal, picrocrocin, crocetin, crocin and quercetin. It has also the inhibitory effects on lipid peroxidation of membrane and, thus, protects cells from oxidative stress. Accordingly, several studies have been demonstrated that saffron has antioxidant activity and reduces oxidative damages in hippocampus, following improvement of spatial learning memory and muscle skeletal during ischemia. All of the investigations on the brain ischemia demonstrated that Saffron has neuroprotective roles. Saffron significantly reduces infarcted areas, which are induced by occlusion of the middle cerebral artery (MCA) in mice, by increased expression of gamma-glutamylcysteinyl synthase (gamma-GCS), the main enzyme for glutathione synthesis. Saffron therapy led to decreased inflammation and increased effects of hypothermia therapy in mice hypoxic ischemia-induced brain injury. Several animal model investigations showed that Saffron and its components have neuroprotective roles via inhibition of the production of free radicals and enhanced antioxidant activities in the ERK1/2 pathway-dependent manner. In Iranian traditional medicine, saffron has been used to cure obstructions inside brain to protect it from oxygen deprivation. Traditionally, the topical use of saffron in the boiling water is good for severe headaches and insomnia. Hopefully, some natural products have antidepressant effects like Saffron. Therefore, new drugs developed from extracts of natural products, especially those that have been shown to have low side effects in the treatment of depression, are becoming increasingly desirable. Antidepressants mainly work by increasing the availability of serotonin and certain other neurotransmitters, thereby reducing depressive symptoms. Depression and anxiety are two frequent and challenging comorbidities of AD. Studies have shown that patients with severe AD were more likely to have depression. Moreover, depression and anxiety could accelerate the progression, and increase the mortality of AD patients. Patients are likely to benefit from saffron because of its antidepressant and anti-anxious effects. Furthermore, Saffron has anti-inflammatory effects because it includes flavonoids, tannins, saponins, and crocins. 

Saffron has four biological active compounds: crocin, crocetin, picrocrocin and safranal. These four compounds are responsible for the high value of the medicinal and nutritional effects of saffron. In addition, saffron contains two essential vitamins: riboflavin (vitamin B2) and thiamine (vitamin B1). In this study, an overview on recent scientific articles on the effective roles of saffron and its compounds in the treatment of neurological diseases such as Alzheimer’s disease, Parkinson’s disease, anxiety, epilepsy, stroke, etc. has been done.

Despite the economic importance of saffron, significant research has not been done in the field of molecular biology and genetics of this plant. Sterility and triploid genome, along with lack of genetic diversity are main reasons for this lack of research. Optimization of saffron cell suspension is a great step forward. It will provide the possibility of studying the production of saffron secondary metabolites, gene transformation, and mutagenesis cellular level. There have been few reports of cell suspension culture in saffron, mainly for the production of secondary metabolites (Yoon et al., 2015; Moradi et al., 2020; Taherkhani et al., 2019). In order to optimize the production of crocin and phenolic compounds, Moradi and co-workers produced calli from saffron stigma and then created a suspension culture from these calli (Moradi et al., 2020). However, the production of embryogenic cell suspension in saffron has not been reported. The aim of the current research was to achieve a cell suspension system with acceptable growth in saffron. For this purpose, different explants were subjected to different hormonal treatments to determine the optimal callus formation and suspension culture media.  Saffron corms were used to prepare explants. The lateral and terminal buds and the base of the corms were removed and the central part of the corms was used to prepare explants. Then, the explants were sterilized with 2.5% Sodium hypochlorite for 15 minutes. Explants were grown on CIM1 to CIM5 media (Table 1). After 5 weeks, the percentage of callus formation and the fresh and dry weight of calli were measured. The calli obtained from CIM2c treatment were used to prepare suspension culture with three different types of culture media (Table 1). To compare the speed of cell growth in different cell suspension treatments, the optical density (OD) measurement method was used. For all the assays, data were analyzed by one-way analysis of variance (ANOVA) followed by Tukey Honestly Significant Differences (HSD) Post-Hoc test using SPSS® statistical software, version 22 (IBM Corp., USA). The graphs were created using GraphPad Prism version 9 for Windows (GraphPad Software, California USA). The results showed that the concentration of 2 mgL-1 of 2,4-D and 1 mgL-1 of BAP had the best performance in callus formation and callus fresh weight. The calli of this treatment were used for cell suspension culture. SM3 medium had the best growth rate in cell suspension culture, but it did not have cells with appropriate shape and form. SM2 medium had a suitable growth rate and cells with small size and dry color, which had the best performance in terms of quality. In order to increase the quality, phenol production control materials were used. Adding PVP increased the growth rate of cell suspension in the SM2 medium. As we have shown, among the auxins 2, 4-D has a greater effect than NAA, contrary to other studies reported (Ahmad et al., 2013; Verma et al., 2016; Safarnejad et al., 2016; Georgiev et al., 2009; Sharma et al., 2008).  The current research showed the effect of treatment of 1 mgL-1 of BAP and 2 mgL-1 of 2,4-D on increasing the percentage of callus formation and the weight of calli taken from the saffron corms. SM2 and SM3 treatments had the best cell suspension growth rate. However, the SM3 treatment had cells with high starch vacuoles. Nevertheless, the SM2 treatment had smaller cells containing pigments.

S Saffron (Crocus sativus L.) a perennial herbaceous is one of the most important crops. It is a valuable ketchup and its demand for consumption has been increased due to many medicinal and pharmacological applications. Saffron is a male sterile and can be propagated only by its corm and produces daughter corms. Cultivation of saffron is challenged by biotic stresses and corm rot as a biotic stress, is one of the most destructive diseases subterranean organs. Because of the insufficient information about corm rot etiology, investigation and identification of harmful agents is essential. Different pathogens such as fungi affect growth of corm and identification of these fungi is critical in cultivation of saffron. Occurrence of saffron corm rot has been reported from many countries and various microorganisms such as Fusarium, Rhizoctonia, Sclerotinia, Penicillium, Aspergillus, Bacillus and Burkhulderia have been isolated from rotted corm of saffron. The present study was conducted to identify fungi associated with corm of saffron in Khorramabad.  Infected corms of saffron were randomly collected from different regions of Khorramabad in Lorestan province (10 regions). The infected tissues were surface-sterilized with sodium hypochlorite (5%) for 1 min, and washed three times by sterile distilled water, dried on sterile filter paper and directly placed on the surface of potato dextrose agar medium. The PDA plates were incubated for 7 days at 25±2°C and then were purified using single spore method. Morpho-cultural characteristics of fungi were studied on carnation leaf agar and potato carrot agar media. Microscopic measurement and images of reproductive structures were carried out under a Nikon microscope. Pathogenicity test was conducted to evaluate the ability of isolates to colonize saffron corms. Conidial suspension was prepared from cultured isolates on potato dextrose broth medium and adjusted at a concentration of 1×106 conidia/ml. To inoculation, saffron corms were submerged in the conidial suspension, then planted in an aseptic soil and maintained for 4 weeks under controlled conditions in a greenhouse with 23 ± 2°C and 70% relative humidity. The disease incidence and severity was inspected daily and finally Koch’s postulates were tested. Totally, 58 isolates were collected and four species including of Alternaria alternata, Fusarium solani, F. acuminatum and F. oxysporum were isolated and identified on the basis of morphological characteristics. The A. alternate (25 isolates) and F. acuminatum (4 isolates) were the most and the least frequent respectively. According to the pathogenic test under the controlled conditions, F. oxysporum was the most aggressive and A. alternate was weakly pathogenic. There was not previous report of incidence of F. acuminatum and F. solani on saffron corm from the world and Iran respectively. The results of this research are in agreement with previous studies that showed corm rot is a major challenge in saffron cultivation. Corm rot is a complex disease and frequency, diversity and distribution of pathogens may be different due to cultivar type, agricultural practices, and climatological parameters. However, Fusarium spp. are the main agent of corm rot and F. oxysporum is the most predominant in saffron growing areas of the world. Moreover, Fusarium spp. have been reported as serious pathogen of subterranean organs of many crops such as potato, rice, wheat, and barley.  The results of this study showed that corm rot is a serious constraint in saffron production. Although A. alternata was the most frequent species in rotted corms, Fusarium spp. especially F. oxysporum were more aggressive and virulent on saffron. In addition, isolating saprophytic fungi such as Aspergillus, Penicillium and Rhizopus in our research showed that saffron corm is potentially exposed to infectious by varous fungi. Etiology of saffron corm rot is essential and results of this study can be helpful in management of saffron cultivation.

Climate change and global warming have increased the intensity of droughts and their continuation. This phenomenon causes improper distribution of precipitation and the available water sources. Temperature and precipitation change under climate change and the agricultural products is affected by these two factors. Iran is the largest producer and exporter of saffron in the world, so that about 90% of the production and cultivated area of saffron in the world belongs to Iran. Meanwhile, 96% of Iran's saffron is produced in Khorasan. Saffron is one of the most efficient agricultural products in terms of water consumption, and it is considered an under-expected plant in terms of the need for nutrients. The aim of this research is investigating the changes in the water footprint of saffron under the past climate changes during the 2006 to 2017 in Khorasan region.
 
In this study, Fuzzy Clustering Method (FCM) was used for clustering homogeneous agroclimatic regions of saffron production using precipitation data (p), minimum and maximum temperature (Tmax, Tmin), humidity, (RH%) count of sunny hours (SH) and wind speed (WS). Then the water footprint components, including green, blue and gray water footprints and the economic value of the water footprint components in the production of saffron during the 2006-2017 were estimated using Hoekstra and Chapagain concept. Finally, the trends of water footprint components and climatic factors were investigated using Man-Kendall trend analysis test and regression analysis.
 
Saffron production regions in Khorasan were divided into three homogenous agroclimatic regions with the help of FCM. Based on the results, the weighted average water footprint of saffron in Khorasan is 2833 M3/kg, respectively, the share of blue, green and 89.81, 18.11. The share of gray water footprint is very small and around 0.005%; The highest water footprint is related to Bejestan county (cluster 2) (4176.8 M3/kg) and the lowest water footprint is related to Beshrouye county (cluster 3) (1609.5 M3/kg). The average economic value of saffron is 0.61 $/M3, the highest and lowest of which belong to Beshrouye and Bejestan counties, respectively (1.03 and 0.40 $/M3). The results of the analysis of the saffron yield trend and water footprint showed that the saffron water footprint components during the studied period have a significant decreasing trend and the saffron yield also has an increasing trend during this period. The results of regression analysis showed that in all clusters, performance has a negative coefficient and a significant value. This means that more than anything, increasing the yield will reduce the water footprint. Also, the trend of climatic variables showed that temperature is increasing and humidity and precipitation are decreasing, but this trend is statistically no significance and weak.
 
The three provinces of North, Razavi and South Khorasan have the highest level of cultivation and production of saffron in Iran. Based on the results, the average annual production of saffron in three clusters is equal to 157.8 tons/year during the studied period. The highest yield of saffron is related to cluster 3 and Faruj county (4.3 kg/ha) and the lowest yield is related to cluster 1 and Bejestan county (2.5 kg/ha). The weighted average of the total water footprint of saffron is 2833 M3/kg, the largest share of water footprint is related to cluster 1 and Bejestan county (3884.8 M3/kg), which according to the results has the lowest yield, and the lowest share of water footprint is related to Cluster 2 and Torbat Heydarieh county (1331.1 M3/kg). According to the results, the highest and lowest economic value of the total water footprint of saffron in the study area is related to cluster 1 in Beshroieh (1.03 $/M3) and Bejestan (0.40 $/M3), respectively. The trend analysis of water footprint components showed that during the studied period, the water footprint components in all three clusters had a significant decreasing trend, and the yield of saffron also had an increasing trend. The trend of climatic variables confirms the increase in temperature and decrease in precipitation, therefore, climate change has occurred in the region, and according to the change of climatic variables and the impact of water footprint on climate change, it is possible to adapt this species to the change by changing the cultivation period or changing the genotype.

The concept of light consumption efficiency is widely used in the analysis of plant growth. Light use efficiency is the amount of dry matter produced (g per square meter) per unit of absorbed radiation (MJ per square meter) by the plant community. Fertilizer management can also play an effective role in increasing the sustainability of production, and one of the main pillars of sustainable agriculture is the use of biological fertilizers in agricultural ecosystems with the aim of eliminating or significantly reducing the consumption of chemical inputs. In a research study, Vejdani Aram et al. (2018) stated that Fertilizer 2 biofertilizer increased the wheat leaf area index by 1.14 to 54%, regardless of the amount of phosphorus chemical fertilizer used. 

In order to evaluate the effects of chemical fertilizer, vermicompost and plant growth promoting bacteria on quantitative and qualitative yields and radiation use efficiency (RUE) of saffron, an experiment was conducted in the saffron research farm of Shahed University, Faculty of Agriculture in 2014-2015.The experiment was performed as a two-factor factorial in the form of a randomized complete block design with three replications. The first factor is chemical nitrogen fertilizer (urea) in three levels of 0, 50 and 100 percentage of the recommended rate of fertilizer based on soil test and the second factor: different types of non-chemical fertilizer in four levels of control, vermicompost (10 tons per hectare), biofertilizer containing Pseudomonas and Bacillus bacteria (PGPR) and a combination of PGPR and vermicompost. It should be noted that the treatments were applied to the saffron plant for year four and this study was conducted in the year fourth. 

In this experiment, the results of the analysis of variance table showed that the main effect of nitrogen chemical fertilizer on the amount of plant dry matter in all three measurement times—the leaf area index in March, the relative growth rate measured in January and March, and the rate of net assimilation—was not significant. In March, light use efficiency, chlorophyll a, chlorophyll b, and total chlorophyll became significant. Also, the main effect of non-chemical fertilizer on total dry matter in all three measurements, plant growth rate, and specific leaf area measured in March was significant. The results showed that the interaction of nitrogen and non-chemical chemicals fertilizers on most physiological growth traits, ecological traits (radiation use efficiency) and photosynthetic pigment traits were significant. However, none of the fertilizer treatments and their interaction on the amount of active ingredient of stigma, number of flowers, fresh weight of petals, fresh weight of stigma and weight of flowers were not significant. Comparison of the mean of interaction showed that the highest amount of chlorophyll b was obtained in 50% and 100% treatments (611 mg/ml) and (569 mg/ml) for nitrogen fertilizer along with vermicompost and biofertilizer treatments, respectively. Also, the highest amount of total chlorophyll in 50% and 100% treatments (1367 mg/ml) and (1301 mg/ml) were related to nitrogen fertilizer with biofertilizer, respectively. The results of total dry matter measurement showed that the use of vermicompost at all three levels of nitrogen fertilizer increased the dry matter content almost at each measurement. The highest RUE (1.027 g/mJ) was related to vermicompost treatment with 100% nitrogen fertilizer, which was not significantly different from most other treatments. 

In general, it can be said that the treatment of non-chemical fertilizers (vermicompost) with 100% nitrogen fertilizer provides much better conditions to improve growth and increase the efficiency of radiation Use in saffron. Therefore, due to the fact that Iran is located in a low-water region of the world, it is necessary to implement and study the effect of different non-chemical fertilizers compared to chemical fertilizers on the quantitative and qualitative performance of saffron under minimal irrigation conditions over several years.

Many of the saffron corms that are planted in the fields do not have the desired weight and have very low potential for flowering in the field conditions. It is hypothesized that due to the elimination of physical resistance of soil and appropriate control of environmental factors in hydroponic cultivation, it is possible to obtain more flowers from small corms in a controlled environment (Behdani & Fallahi, 2015). In some previous studies (Molina et al., 2005; Mollafilabi, 2014; Aghhavani-Shajari et al., 2021) saffron flowering capacity under controlled environment has been evaluated, but using large mother corms. The main goal of this research was to investigate the possibility of producing flowers from very small saffron mother corms in a controlled environment.
 
In this study, the effect of mother corm weight (2-4, 4-6, 6-8 and 8-10 g) on saffron flowering characteristics was investigated under controlled environment, in a completely randomized design with four replications, in horticulture laboratory, University of Birjand, Iran. Flower initiation stage was passed in the soil (in field), but the flower emergence stage took place under controlled conditions (Temperature: 15±1 °C, relative humidity: 75% and light frequency: 8 hours of light and 16 hours of darkness) (Mollafilabi, 2014; Aghhavani-Shajari et al., 2021), with a planting density of 500 corms per m-2. Some properties of used water in hydroponic production system has been provided in Table 1. The studied traits were number of flowers, flower yield, mean flower weight, flower length, stigma and style length, as well as dry weights of stigma, style and petals. Data analysis was done using SAS ver.9.2. Means were compared by FLSD at 5% level of probability.    
 
The results showed that the number of flowers produced in the weight groups of 2-4, 4-6, 6-8 and 8-10 g, were 0, 56.2, 193.7 and 425 No m-2, respectively (Fig 1), which indicates the production of at least one flower per corm is 0, 11.2, 38.7 and 85% of the corms in the mentioned weight groups of corms, respectively. This can probably indicate that regardless of the cultivation environment (field or hydroponic), very small corms are not able to produce flower or their flowering capacity is very limited (Behdani & Fallahi, 2015; Fallahi et al., 2018). Flower yield in the weight groups of 2-4, 4-6, 6-8 and 8-10 g were 0, 24, 96.6 and 198 g m2, respectively (Fig. 3), and dry pistil yield (style & stigma) were 0, 0.25, 0.98 and 2.13 g m-2, respectively (Fig. 7). Under field conditions and planting the corm in the soil at a depth of about 20 cm, usually the mother corms weighing 4-6 g rarely have the ability to flower (Behdani & Fallahi, 2015). The results of this experiment showed that planting these corms in hydroponic environment makes at least 11% of them produce flowers. It seems that if both stages of saffron flowering (flower initiation and flower emergence) are spent in a controlled environment, a higher percentage of small corms are able to produce flowers. The results of this research, compared to the field experiments that have been done on saffron before (such as Fallahi et al., 2018), showed that the cultivation of saffron in a controlled environment can lead to the flowering of a higher percentage of corms, and this advantage increases significantly with the increase in the mother corm weight.

Introduction

The Crocus genus from the Iridaceae family has more than 70 ornamental species that are very valuable because of the beautiful color of the flower and are used in gardening and green spaces. Among the industrial and export products of Iran, saffron has found a special place as the most valuable agricultural and medical product in the world. The most important compounds in saffron are crocin, picrocrocin, and safranal, which are responsible for color, smell, and taste, respectively. The new approach to producing medicinal plants goes towards increasing the quantity and quality of the effective substance by using sustainable and organic farming methods, so using organic fertilizers in growing medicinal plants becomes necessary to achieve these goals.
 

This research was conducted based on a randomized complete block design with four replications in a saffron farm in Kashmar city and Gorgan University of Agricultural Sciences and Natural Resources Laboratory. Treatments include Kelp seaweed extract in four concentrations (0, 1, 2, 3 mg.l-1), tea compost (0, 200, 300, 400 mg.l-1) and lignin (0, 500, 1000, 1500 mg.l-1). The treatments were carried out at the end of September along with the first irrigation. The research farm was in the sixth year of saffron cultivation. The planting distance was 20×30 cm and 15 corms were planted per square meter. The weight of the corms was 8-10 grams. Sampling from each experimental unit was done randomly. 10 plants were randomly selected from the middle of each plot. The flower was harvested during two weeks and at the beginning of the day, and then the petals were separated from the stigma. After harvesting the flowers and stigmas, they were transferred to a room with a temperature of 21-25 degrees Celsius and relative humidity of 41-52% for drying, using the dry shade method. The measured variables included total phenol, total flavonoids, antioxidant activity, anthocyanin in stigma and petal tissues, and total safranal, total crocin, and total picrocrocin in stigma tissue.

The results showed that the treatments were significant at one percent. The mean comparison showed that the highest amount of stigma total phenol (6.75 mg.g-1) was observed in 3 mg.l-1 of seaweed treatment, and the highest amount of stigma total flavonoids (2.04 mg.g-1) was seen in the interaction of 500 mg.l-1 of lignin, 1 mg.l-1 seaweed, and 200 mg.l-1 tea compost. The highest amount of petal anthocyanin (0.42 mg.g-1) was recorded in 2 mg.l-1 seaweed treatment, the highest percentage of stigma antioxidant capacity (10.47%), and the highest amount of stigma anthocyanin (0.047 mg.g-1) was observed in the control treatment. Based on the results of the mean comparison, no difference was observed between most of the treatments, but the treatment of 1500 mg per liter of lignin (47.24%) increased lignin with a small difference. The lowest amount (24.16%) was related to the 500 mg. l-1 lignin treatment. According to the amount of crocin in the control, it can be concluded that the treatment did not have a great effect on the amount of total crocin in saffron.
 

Finally, it can be concluded that seaweed fertilizers, lignin, and tea compost had a good effect on the saffron plant, and considering the economic importance of this plant, using biological and organic fertilizers as much as possible and replacing them with chemical fertilizers has a positive effect in agriculture. So that, this research had the highest number of flowers and the highest stigma weight in compost tea treatment, which is one of the important factors desired by most farmers. In some treatments, a high level of phenol and anthocyanin in the petals compared to the stigma was seen, which makes pay more attention to the metabolites of the petals, and in some cases, even more advantages than the saffron stigma.