مطالعه اثرات کود دامی و زئولیت بر کارایی جذب و مصرف نیتروژن زعفران (Crocus sativus L.) تحت شرایط کم آبیاری

جهت تعیین کارایی جذب و مصرف نیتروژن و میزان عملکرد کلاله خشک و بررسی تعداد بنه زعفران (Crocus sativus L.) در مزرعه دانشگاه فردوسی مشهد، ۱۴۰۲-۱۴۰۱ سطوح مختلف کود دامی و زئولیت تحت شرایط کم آبیاری، پژوهشی در سال به صورت اسپلیت، اسپلیت پالت بر پایه طرح بلوک های کامل تصادفی با سه تکرار اجرا شد. تیمارهای آزمایش آبیاری در سه سطح (۵۰، ۷۵ و ۱۰۰ درصد نیاز آبی)، استفاده ازکود دامی در سه سطح (۹، ۱۸ و ۲۷ تن در هکتار) و زئولیت در سه سطح (۰، ۳ و ۶ تن در هکتار) درنظرگرفته شد. نتایج نشان داد در تیمار آبیاری کامل (۱۰۰ درصد نیاز آبی)، ۲۷ تن در هکتار کود دامی و ۶ تن در هکتار زئولیت نسبت به تیمار ۵۰ درصد نیاز آبی، ۹ تن در هکتار کود دامی و بدون زئولیت افزایش به ترتیب ۱۵ درصدی حداکثر شاخص سطح برگ، ۱۰۷ درصدی وزن خشک برگ و ۳۰ درصدی وزن خشک کلاله بدست آمد. بیشترین عملکرد کلاله خشک در تیمار ۱۰۰ درصد نیاز آبی و تیمار ۲۷ تن در هکتار کود دامی و ۶ تن در هکتار زئولیت حاصل شد. در شرایط آبیاری کامل و کود دامی ۲۷ و ۶ تن در هکتار زئولیت نسبت به آبیاری ۷۵ و ۵۰ درصد به ترتیب به میزان ۳۰ درصد و ۴۷ درصد تعداد بنه با وزن ۷-۹ و ۵-۷ گرم افزایش یافته و افزایش ۲۱۷ درصدی در کارایی جذب نیتروژن و افزایش ۴۸ درصدی در کارایی مصرف نیتروژن مشاهده شد.

Introduction: Saffron, scientifically known as Crocus sativus L., has a dark red, cream yellow, and orange color and a strong odor. Saffron also has stigmas of various shapes and is used in the food, pharmaceutical and raw dyeing industries. This plant is cultivated in an area of about 123,000 hectares of land in the world, and 85,000 hectares are under cultivation in Iran. According to statistics, 94% of the world’s saffron is attributed to Iran. The saffron plant has been introduced into regional cultivation patterns due to its high drought tolerance. The use of animal manure in saffron fields, in addition to improving nutrients and preventing soil compaction, also increases corm growth. Zeolites are alkaline porous honeycomb structures of various shapes that reduce the toxicity of heavy metals in the soil such as cadmium, lead and nitrogen and manage irrigation efficiency. The main objective of this research is to investigate the water absorption efficiency and water consumption of saffron, which was carried out based on the different effects of zeolite and animal manure on water conditions. Materials and Methods: In order to investigate the efficiency of nitrogen absorption and utilization and stigma yield of saffron at different levels of manure and zeolite under deficit irrigation conditions, a study was conducted in the 2022-2023 crop year at the research farm of the Faculty of Agriculture, Ferdowsi University of Mashhad. This study was conducted in split-split plots based on a three-block basic design. Experiments were conducted with irrigation treatment at three levels (50, 75 and 100 percent of water requirement) as the main factor, manure consumption at three levels (9, 18 and 27 tons per ha) as a secondary factor, and zeolite consumption at three levels (0, 3 and 6 tons per ha) as a secondary factor. Results: This study was conducted to investigate the effect of different levels of manure and zeolite on leaf area index, leaf dry weight, stigma dry weight, corm number (5-7, 7-9 grams) and nitrogen uptake and utilization efficiency of saffron under drought conditions. The results showed that under full irrigation, complete manure and complete zeolite conditions, we witnessed an increase in leaf area index and leaf dry weight. Also, in terms of stigma dry weight and saffron corm number under full irrigation, complete manure and complete zeolite conditions, the highest stigma dry weight and corm number (5-7, 7-9 grams) were obtained. Under full irrigation, complete manure and complete zeolite conditions, the percentage of saffron nitrogen uptake and utilization efficiency increased significantly. Simultaneous application of manure and zeolite reduced the negative effects of drought stress on saffron agronomic characteristics. From the perspective of nitrogen uptake and utilization efficiency, it was found that treatments with full irrigation, along with the highest levels of manure and zeolite, provided the highest nitrogen uptake and utilization. Conclusion: The targeted co-application of manure and zeolite effectively mitigates drought stress, thereby enhancing nitrogen use efficiency and increasing saffron stigma yield.