نشریه زراعت و فناوری زعفران
سال سوم شماره 2 (پیاپی 8، تابستان 1394)

Increasing the concentration of different heavy metals, such as lead, copper, nickel and other heavy metals in air, soil and water can pose negative effects on the entire ecosystem and cause harmful health consequences for all forms of life. The major sources of pollution in many parts of world are overburdens of mine, industrial effluents, fertilizers and pesticides. In order to study the effects of different heavy metals on some of the physiological attributes of saffron such as photosynthetic pigments, Prolin and carbohydrates of leaf and the amount of crocin in the saffron stigmas, an experiment was conducted based on completely randomized design (CRD) with four replications and seven treatments. The experimental treatments were control and six different heavy metals (i.e. nickel nitrate, silver nitrate, zinc nitrate, copper carbonate, lead nitrate and manganese sulfate). Before sowing the corms, all of the heavy metals were added to the soil based on the concentration of 500 mg.kg-1 soil. The effects of experimental treatments on chlorophyll a, chlorophyll b, total chlorophyll and chlorophyll a/b were significant, but there was no significant effect on leaf carotenoids. Proline and soluble carbohydrates were significantly affected by the treatments. However, the effects of these treatments on reducing carbohydrates were not significant. Heavy metals also had significant effects on crocin content of the saffron stigmas. By using all of the heavy metals except for nickel nitrate, the amount of crocin increased.

In order to investigate the effective traits on yield of saffron ecotypes, a study was carried out as a split plot in time based on randomized complete block design with three replications in the research farm of Zanjan University during the growing seasons of 2013-2015. Eighteen saffron ecotypes were studied in this experiment. The traits of number of flowers, fresh weight of flowers, fresh weight of stigma, dry weight of flowers, dry weight of stigma, stigma length and dry stigma yield of saffron were measured. The results indicated that there were significant differences among all studied traits of ecotypes except for stigma length. The correlation matrix revealed that the number of flower and dry weight of stigma had a positive and highly significant correlation with dry stigma yield (r= 0.99 and 0.70, respectively). Analysis of stepwise regression and path analysis showed that the traits of number of flowers, dry weight of stigma and dry weight of flowers were the most effective traits on dry stigma yield. Therefore, these traits can be used to achieve a higher stigma yield.

In order to evaluate the adaptability of saffron ecotypes under Maragheh climatic conditions, an experiment was conducted based on a Randomized Complete Block design (RCBD) with three replications during the growing seasons of 2013 and 2014. The ecotypes used were Bardaskan, Abrud, Sabzevar, Bonab1, Torbat-e-Heydarieh, Bonab2, Marand1, Marand2, Kashmar, Taybad, Esfiukh and Mahvelat. The following traits were evaluated: fresh weight of stigma, dry weight of stigma, length of stigma, emergence percentage, emergence rate, flowering percentage, flowering rate, dry and fresh weight of flowers and dry yield of stigma in the area. The results showed that the ecotypes established very well in the first year of the experiment, but frosty days of the winter severely damaged Abrud, Taybad and Esfiukh ecotypes. There were significant differences among the ecotypes for the traits: the number of flowers, emergence, flowering percent and fresh weight of saffron. Also, a significant difference was recorded among the studied ecotypes for flowering and emergence rate. The highest emergence percentage was observed in Marand 2, while Sabzevar had the highest rate of flowering and flowering percentage. Despite the low yields for Marand1 and Sabzevar in the first year of the experiment, these ecotypes with 1.5 and 1.4 kg per hectare produced the high stigma yields, respectively in the second year. In conclusion, the results showed that the ecotypes of Marand are suitable for cultivate in the Maragheh climate conditions and the use of exotic corms is not recommended.

The predicted models for crops yield are developing rapidly by the creation of new statistical techniques and neural networks. For this purpose, a research was carried out in the Torbat-e-Heydarieh region for predicting yield and water use efficiency of saffron by using an artificial neural network model. The model was calibrated and validated by using crop yield and climate parameters data during 2009-2010. The models were evaluated by using indices of correlation coefficient (R2), root mean squares error normalized (RMSEn), and mean squares error (MSE). The results showed that the suggested neural network (model No. 9) with having 2 hidden layers, 8 neurons, and R = 0.97 (for saffron yield); and 1 hidden layer, 7 neurons, and R2= 0.90 (for water use efficiency) had a high accommodation with these two factors. Also, according to the indices RMSEn and MSE, model No. 9 simulated the yield and WUE of saffron with a high accuracy, such that RMSEn and MSE for yield in this model obtained were 2.78% and 0.0041, respectively; and for WUE they were calculated to be 5.41% and 0.0073, respectively. Also, the results of sensitivity analysis indicated that irrigation is the most important parameter for predicting yield and WUE, and after that is precipitation and solar radiation. Generally, use of the suggested neural network in this research can improve saffron cultivation in the Torbat-e-Heydarieh region.

One of the Iran's agricultural problems is the decrease in native products. The objective of this research is to study the reasons for cultivating saffron in the temperate mountainous regions of the Golestan province. Accordingly, the type of research is both applied and developmental and its methodology is descriptive-analytical. The field of research includes the farms of Vamnan village in the Azadshahr County. Its statistical society is 110 farmers who are experienced in saffron cultivation. Data was collected from the Census carried out through questionnaires, and was analyzed and interpreted by SPSS. The results have shown that, in comparison to other local products, saffron is more climatically resistant, in so far as 82.1% of farmers, in their prioritizations to cultivate agricultural products, have named saffron as the first one. This rate is usually low among other products. From the income indicator perspective, saffron cultivation income is more than the income from cultivation of other local products. To compare, saffron income is (92,372 thousand Rials), while for potatoes it is (5983 thousand Rials) and for cereals it is (9617.2 thousand Riyals). In addition, there is a meaningful relationship of 99% between people’s interest to grow saffron and its economic conditions on the one hand and physiological features on the other hand. Lack of the necessary infrastructure and markets in the region, lack of drying machines, and shortage of labor are stated as the greatest obstacles to the development of saffron in the area. Therefore, obstacles in the development of saffron in the region are essential.

Climate is an important factor in the development of industrial tourism. The group travels to heal with climate. Elevation, moderate temperature and suitability of landscape are factors that are required to consider as conditions for tourism. There are some benefit such as center of cultivating barberry and saffron, a moderate climate and being located in transportation axis of east of Iran in the city of Ghaen that make it have a in high potential to absorb tourists. A review of climate convenience with bioclimatic indices such as W-strain and W_Sens shows that the first month of the spring and autumn in Ghaen, the climate is suitable for travelling, especially for the beautiful landscapes of barberry and saffron. Therefore, combining the moderate climatic and the beautiful landscapes of barberry and saffron can provide good conditions for agriculture tourism. Saffron tourism master span is the accurate and reasonable title in areas where the crop is grown, and studied. It is also a tourist profile. In this study, using the ecological indicators of climate such as severe weather, heat stress, cooling power of wind during the 22 years in Ghaen station. Bioklima software was used to investigate the climate comfort. This city provides such a situation that in the first months of spring and autumn, weather conditions are fit for tourists and for recreation and travel. Especially, the early autumn harvest of saffron in the city plus the beautiful scenery can attract travelers. So, combining the two factors of moderate climate and harvest of Saffron work hand in hand to attract tourism. Therefore, these two factors combined (a moderate climate and harvesting saffron) create beautiful scenes and can provide conditions for the development of agricultural tourism.