| چکیده انگلیسی مقاله |
Background and objectives: Saffron (Crocus sativus L.) is one of the most expensive spices in the world, and due to the high demand for it in the world markets, its cultivation is developing strongly. In addition to genetics, the region's climate and soil characteristics also affect the quantity and quality of the product. Therefore, identifying regions, whose climatic and soil conditions are close to the optimal conditions for saffron production will help us achieve the most favorable quantitative and qualitative performance. Materials and methods: In the present study, saffron was cultivated in six different regions of Kurdistan province (Sanandaj, Kamyaran, Ghorveh, Dehgolan, Divandarreh, and Marivan) as a randomized complete block design, and their functional and phytochemical characteristics were evaluated during three years (2020-2022). The saffron corms used in this research were prepared from Torbat-e Heydarieh city. In each region, land with an area of 25 m2 was selected. After preparation, three plots with dimensions 2x2 m with 1m distances were created. Each experimental plot consisted of 10 rows, and in each row, 20 holes were made with a depth of 15 cm and a distance of 10 cm from each other, and then one corm was planted in each hole. Irrigation was done twice a year (late September and late October). During the flowering season, saffron flowers were harvested, and their functional and phytochemical characteristics (number of flowers, dry flower yield, dry stigma yield, stigma length, crocin, and safranal content of the stigma) were measured. Total monthly precipitation and average monthly temperature for each region during the research period were obtained from nearest meteorological station. The physicochemical properties of soil samples from the studied regions were evaluated in the laboratory. Finally, the mean comparison of data (using Duncan’s multiple range test) and correlations between climate and soil data with functional and phytochemical traits (using the Pearson method) were obtained by SPSS software. Results: The results indicated that the maximum stigma yield in all three years belonged to saffron cultivated in Kamyaran (0.13±0.009, 1.27±0.085 and 1.54±0.052 g/m2 in 2020, 2021, and 2022, respectively). In all three years, the highest crocin content was obtained from the stigmas harvested from Divandarreh farm (53.01±15.77, 92.54±26.6 and 143.07±5.12 mg/g dry stigma in 2020, 2021 and 2022, respectively). The highest mean of safranal content in the year 2020 (4.09±0.38 mg/g dry stigma), 2021 (2.48±0.44 mg/g dry stigma), and 2022 (5.05±0.14 mg/g dry stigma), belonged to the saffron of Kamyaran (no significant difference with other regions except Marivan), Marivan (no significant difference with Dehgolan and Divandarreh) and Divandarreh (no significant difference with other regions except Kamyaran), respectively. Dry flower yield and stigma yield showed a significant negative correlation with clay
(r= -0.329* and r= -0.356**, respectively), organic matter (r= -0.422** and r= -0.428**, respectively) and nitrogen (r= -0.437** and r= -0.444**, respectively), and a significant positive correlation with potassium (r= 0.544** and r= 0.561**, respectively) and phosphorus
(r= 0.410** and r= 0.435**, respectively). The crocin content of stigma had a significant positive correlation with clay (r= 0.557**) and pH (r= 0.438**) and a significant negative correlation with sand (r= -0.461**). Safranal had no significant correlation with soil characteristics and altitude. Also, significant correlations were obtained between the measured traits and average monthly temperature and total monthly precipitation. Conclusion: Generally, regions of Kurdistan province with less rainfall in spring, summer and early autumn; more rainfall in late autumn and during winter; higher average monthly temperature; with medium-textured soils containing more phosphorus and potassium, lower nitrogen and organic matter, and slightly alkaline pH, were identified as more suitable regions for saffron production. Based on all measured quantitative and qualitative traits, among the studied regions, Kamyaran had the most suitable conditions for saffron production. |