بررسی تاثیر فرآیند خشک کردن بر ویژگی های رنگی گلبرگ زعفران با استفاده از ماشین بینایی

خشک کردن یکى از روش هاى رایج براى افزایش ماندگارى گیاهان دارویی و محصولات کشاورزى است. در این پژوهش، فرآیند خشک کردن گلبرگ های زعفران با خشک کن هوای داغ لایه نازک در پنج سطح دمای 40، 60، 80، 100 و 120 درجه سلسیوس و سه سرعت هوای 5/0، 1 و 5/1 متر بر ثانیه و تاثیرات آن ها بر پارامتر های رنگی (مقادیر G ,R و B) مورد بررسی قرار گرفت. به کمک سامانه ماشین بینایی، تصاویر رنگی از نمونه های خشک شده گلبرگ زعفران، دریافت و با استفاده از الگوریتم های پردازش تصویر، مورد پردازش قرار گرفت. ویژگی-های رنگی (RGB) آن ها نیز استخراج گردید. از سوی دیگر میزان آنتوسیانین به روش pH افتراقی و ویژگی هایL*a*b* نمونه ها به منظور تعیین شرایط مناسب خشک کردن اندازه گیری شدند. داده های حاصل با استفاده از آزمایش فاکتوریل در قالب طرح کاملا تصادفی مورد تجزیه و تحلیل آماری قرار گرفتند. نتایج بررسی نشان داد بیشترین مقادیرRGB مربوط به محدوده دمای 80 تا 100 درجه سلسیوس است که نشان دهنده ی بیشترین نسبت و شدت رنگ های قرمز، سبز و آبی می باشد. همچنین در این بازه دمایی بیشترین میزان آنتوسیانین (21/482 میلی گرم بر لیتر) و کمترین مقدار تغییرات رنگ (∆E) بدست آمد که مطلوبیت نسبی این بازه برای خشک کردن گلبرگ های زعفران را نشان می دهد.

Background and Objective: Saffron (Crocus sativus L.) is considered one of the most valuable medicinal and spice plants in the world, which can be cultivated in most regions of the country due to its low water requirement and good adaptation to environmental conditions. Fertilizer management is an important factor in the successful cultivation of medicinal and spice plants, and nutrients play a significant role in increasing saffron yield. Urban waste compost, as an organic fertilizer, not only contains macro and micronutrients but also enhances the availability of these elements. Therefore, this study was conducted to evaluate the effect of compost on the absorption of micronutrients (iron, zinc, copper, and manganese) in the plant organs of saffron and its relationship with agronomic traits and yield. Materials and Methods: The experiment was carried out during the 2015-2016 growing seasons as a randomized complete block design at the Faculty of Agriculture, Birjand University. The treatments included four levels of urban waste compost (0, 5, 10, and 20 tons per hectare) with three replications.The measured traits included the concentration of micronutrients in (soil, leaves, corms, and saffron stigmas), photosynthetic pigments (chlorophyll a, b, carotenoids, and total chlorophyll), and agronomic traits (fresh and dry leaf weight, flower yield, average fresh flower weight, and dried stigma yield).
Findings: The results showed that municipal waste compost had a significant effect on the concentration of copper, iron, and manganese (in soil, corms, and stigmas) of saffron compared to the control. The highest concentrations of iron (3.038 and 4.334 mg/kg), manganese (1.980 and 3.116 mg/kg), and copper (1.094 and 1.802 mg/kg) in flowers and corms were observed at the level of 20 tons per hectare of municipal waste compost, while the lowest levels of these traits were found in the control. The concentration of zinc in soil and leaves also increased with the application of municipal waste compost compared to the control. The highest zinc concentrations (1.633 and 1.240 mg/kg) in soil and leaves were observed with the application of 20 and 10 tons per hectare of municipal waste compost, respectively. Additionally, the results indicated a significant effect of municipal waste compost on leaf carotenoids and total chlorophyll, as well as on saffron flower and stigma yield. The highest flower and stigma yield was obtained at the level of 10 tons per hectare of municipal waste compost.Conclusion: Overall, the results of this study showed that the application of compost, due to the presence of both macro and micronutrients in its composition and the increased uptake of these nutrients by saffron, led to an improvement in agronomic traits and the yield of this plant in this experiment. In summary, the treatment of 5 tons per hectare of compost was identified as the best treatment in this experiment.