نشریه زراعت و فناوری زعفران
سال سوم شماره 1 (پیاپی 7، بهار 1394)

Saffron is cultivated in most part of Iran، because of low water requirement and well adaptation to diverse environmental condition. In recent years، for many reasons such as low water requirement، saffron cultivation areas has been increased especially in Khorasan Razavi province. Temperature is one of the most important factors in saffron flowering phenomena. The aim of this research was to evaluate the response of saffron to temperature in Khorasan Razavi province counties (Torbat-e-Heydarieh، Gonabad، Nishabour، Sabzevar and Ghoochan). Climatic data (monthly minimum، average، maximum temperatures and diurnal temperature range) and saffron yield data were collected for past 20 years period. The stepwise regression methods were used to remove extra parameters and only keep the most important ones. By using these equations and ArcGIS software zoning، Spline method was find the best for saffron crop zoning. The results of linear regression in Gonabad showed that minimum، maximum and average temperature and also diurnal temperature range in March and April months had the greatest impact on saffron yield. For each of the four indices (the minimum، maximum and average temperature and also diurnal temperature range) the best area for saffron cultivation was the southern part of the province (particularly Gonabad); so by increasing distance from this area to north areas (such as Kashmar، Torbat-e-Heydarieh، Sabzevar، Nishabour، Mashhad and finally Ghoochan) saffron yield reduced by 30 to 50 percent. Therefore، the northern areas of the province had relatively low saffron yield. According to result of this research، saffron yield in Khorasan Razavi province was significantly influenced by temperature parameters. Flowering which basically is the most important stage of plant growth، is directly setting up with temperature.

This study was conducted in two factorial experiment based on completely randomized design with three replications at research laboratory of faculty of agriculture in University of Birjand in 2013. Factors included saffron organs at 2 levels (leaves and corms) and water extract concentrations at 5 levels (0، 0. 5، 1، 1. 5 and 2 percent). The allelopathic effects of saffron leaves and corms on seed germination and seedling growth characteristics of flixweed (Descurainia sophia L.) and downy brome (Bromus tectorum L.) were studied in two separate experiments. Results indicated lowest seed germination percentage of downy brome and flixweed were observed at concentration of 2% of corm extract (by 65% and 66% reduce compared to control، respectively). The rate of germination of downy brome decreased (by 71% compared to control) with concentration of 2% of leaf extract but the rate of germination on flixweed was not significantly affected by extract concentrations. Different concentrations of leaf and corm extracts significantly decreased length and weight of plumule and radicals of two weeds. A logistic model provided a successful estimation of relationship between leaf water extract and germination percentage of two weeds. Based on orthogonal comparison tests، the allelopathic inhibition effects of saffron leaves and corms were more on downy brome and flixweed، respectively.

In order to investigate the effects of first irrigation date and organic fertilizers on growth and yield characteristics of saffron، an experiment was conducted as a split-plot based on a randomized complete-block design with three replications، in Khaf city during growing season 2013-2014. Date of first irrigation treatment in three levels (15 September، 30 October and 15 November) was allocated as main plots and fertilizer treatment in five levels (control، humic acid at 5 and 40 liters per hectare، cow manure at 5 and 40 t. ha-1) was set as subplots. Analysis of variance showed that the date of first irrigation had a significant effect on all studied traits except for total fresh weight of corm and the average weight of corm of saffron. Effects of different organic fertilizer treatments on all studied traits were significant، except for corm number with 8 g (8. 00) weight were obtained in first irrigation on 6th November. The first irrigation at 7th October was superior to the other irrigation treatments for corm number with

This study estimate the effect of exchange rate fluctuations on saffron export demand. To this end، the pooled mean group (PMG) approach is used in order to implement the model of auto regressive distributed lag model (ARDL) and vector error correction model (VECM) in the context of panel data. The results showed that، relative price of exports has a negative and significant effect on Iran''s saffron export demand. In the short- and long-term، the estimated price elasticity suggests that Iranian saffron export demand is price inelastic. The results indicate that real income effect of importing countries on the export of Iranian saffron is positive. In the short-term، income importing countries has no significantly effect on Iranian saffron export demand، while the long-term effect is significant at the 0. 01 level. In both short- and long-term، the results indicate that exchange rate has a significant، positive effect on Iran''s saffron export demand. The exchange rate elasticity of export demand for Iran''s saffron is elastic in both short- and long-term. Therefore، the devaluation of the Rial، Iran''s currency، led to a significant increase in the export of Iranian saffron. Also، the results showed in the short-term، the unpredictability of exchange rate fluctuations lead to increase the degree of risk aversion of exporters of Iranian saffron and so they prefer to deal with this issue by reducing their export. However، in the long-term، the income effect dominates the substitution effect، and exchange rate fluctuations has a positive effect on the export of Iranian saffron by creating profit opportunities.

Considering the position of saffron in Iran''s non-petroleum export basket، establishing proper export strategy through concentrating marketing activities in markets with high priority is inevitable. This study ranks export goal markets of different Iran''s packaged saffron using annual data of 2010-2012. To this end، three approaches of numerical taxonomy، TOPSIS and weighted riddling were applied. Results revealed that priorities for exporting different saffron powder in 10 to 30 g packages include Spain، UAE and Italy، for saffron in less than 10 g packages these priorities include Saudi Arabia and Spain، for saffron in 10 to 30 g packages (tariff code 09102013) these priorities include UAE، Spain and Saudi Arabia. Numerical taxonomy approach showed that for different saffron powder in 10 to 30 g packages Saudi Arabia and Spain، saffron in less than 10 g packages Saudi Arabia and Spain، and for saffron in 10 to 30 g packages (tariff code 09102013) United Arab of Emirates، Spain and China are heterogeneous markets. Results of TOPSIS approach showed that for exporting different saffron powder in 10 to 30 g packages and saffron in less than 10 g packages Spain is the first priority and for saffron in 10 to 30 g packages (tariff code 09102013) United Arab of Emirates is the first priority. In weighted riddling approach according to the experts'' viewpoints the weight of import demand index considered as 50% and the other indices weights equal 8. 3%. Results of this approach revealed that for exporting different saffron powder in 10 to 30 g packages and saffron in less than 10 g packages Spain was the first priority. Also، for exporting saffron in 10 to 30 g packages (tariff code 09102013) United Arab of Emirates was the first priority. Based on these results، for ranking markets in order to export different packaged saffron، using weighted riddling and TOPSIS methods results and for ranking homogenous markets (considering used indices) applying numerical taxonomy results were advised.

In this research، the statistics of daily temperature of meteorology stations for estimating the probable occurrence of the first and last frost temperature، the phonological thresholds of saffron and its flowering and irrigation dates were explored. Furthermore، by applying different methods، the probabilities of the attained dates in different probability levels were fit in Smada software. The estimated probability level of 95 percent، as the optimum date، was donated for the entire Isfahan province in ArcGIS9/3 software environment using the interpolation method of Cokriging. The time of occurrence of minimum temperatures is under the influence of the geographical and height condition of each region and the first fall season frost occurs in high regions of the eastern half of Isfahan province at the beginning of November and in the low-lying eastern regions in the late December. The occurrence of daily temperature is changeable from the first half of October and the second half of November. From the west to the east of Isfahan، the time of occurrence of this threshold has a delay of about one month. The optimum flowering date of saffron، based on climatic conditions، is from the first half of October to the late of November. By considering the flowering date and daily temperature requirement of saffron، the irrigation date prior to flowering continues from the second half of September in the western parts and the beginning of November in the eastern regions. From the perspective of thermal condition، the western، central، northern and eastern parts of Isfahan province are more suited to the cultivation and development of saffron product. The amount of water requirement in the study area based on evapotranspiration and crop coefficients of saffron occurred in the mid-season، late season and Initial.

In this study parameters of daily and monthly rainfall، minimum، average and maximum temperatures، relative humidity، number of sunny hours and number of freezing days in the towns of Kashmar and Ghaen were analyzed for a statistical period of 20 agricultural years (1992-2011). Several traditional methods of climate classification were used to compare climate conditions of Ghaen and Kashmar towns by climate determining software. Then effective meteorological indicators on saffron cultivation were selected. Results of climate classification by traditional methods showed that these towns are located in the same climate class. Although the climate was similar، but studies showed that saffron quality in color، odor and taste in Ghaen was higher than Kashmar. The Maximum temperature and relative humidity were the same in both towns. Relative humidity in both towns was the same، especially in October and November which coincided with the beginning of saffron flowering time. Minimum temperature and sunny hours made climate conditions of Ghaen at more favorable for saffron because of mountainous nature. Sunny hours in Ghaen during flowering season was more than Kashmar. Finally، a slight difference in three climate parameters، i. e. rainfall during summer، temperature and sunny hours cannot be the only reason for lower quality of saffron in Kashmar in comparison to Ghaen and saffron quality in Kashmar could be highly raised by other factors such as better planning and management.