اثر کاربرد خاکی سرباره مس و ترکیبات آلی بر فراهمی آهن و رشد گیاه سورگوم

نوع مقاله: کاربردی

نویسندگان

1 گروه علوم خاک دانشگاه علوم کشاورزی و منابع طبیعی گرگان

2 عضو هیات علمی دانشگاه علوم کشاورزی و منابع طبیعی گرگان

3 دانشگاه علوم کشاورزی و منابع طبیعی گرگان

4 استادیار دانشکده عمران دانشگاه صنعتی سیرجان

چکیده

از میان عناصر غذایی کم مصرف، کمبود آهن بیشترین محدودیت را برای محصولات کشاورزی دارد. در این تحقیق امکان استفاده از سرباره مس به عنوان منبع تأمین‌کننده عناصر غذایی در یک خاک آهکی مورد ارزیابی قرار گرفت. ازآنجایی که حدود 8/53 درصد سرباره را اکسیدهای آهن به خود اختصاص می‌دهند، امکان کاربرد آن را به عنوان کود تقویت می‌کند. تأثیر سرباره به همراه ترکیبات آلی بر فراهمی آهن و رشد گیاه سورگوم به صورت آزمایش فاکتوریل در قالب طرح کاملاً تصادفی انجام شد. تیمارهای آزمایشی شامل 5 سطح ماده آلی (پوست پسته، کود گاوی در دو سطح 2 و 4 درصد وزنی و نمونه شاهد) و 11سطح آهن(سرباره مس، سرباره مس با گوگرد، سرباره مس با گوگرد و تیوباسیلوس، سرباره اسیدی (هر کدام دو سطح) کلات سکوسترین، محلول پاشی EDTA و شاهد) بودند. استفاده از سطوح سرباره اسیدی با افزایشEC و نسبت جذب سدیم، کم‌ترین میزان آهن قابل جذب خاک را ایجاد کردند. کاربرد سرباره به میزان 4 برابر مقدار توصیه آزمون خاک، افزایش آهن، روی قابل جذب خاک و غلظت آهن گیاه را در پی داشت. مقایسه ترکیبات آلی نشان داد کودگاوی در مقایسه با پوست پسته در مقدار آهن قابل جذب خاک، میزان عملکرد گیاه، غلظت و جذب آهن گیاه تأثیر‌گذاری بیش‌تری داشته، از طرفی با کاهش غلظت فلزات سنگین استفاده از آن در مقایسه با پوست پسته توصیه می‌شود. مقدار روی، نیکل و کبالت در گیاه مورد بررسی از حد مجاز تجاوز نکرد. لـذا سرباره مس پتانسیل استفاده به عنوان یک کود را در خاکهای آهکی دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of copper slag and organic compounds application on iron availability and growth of Sorghum plant

نویسندگان [English]

  • Elham Mirparizi 1
  • Mojtaba Barani motlagh 1
  • Alireza Movahedi 2
  • REZA GHORBANINASRABADI 3
  • Somayeh Bakhtiary 4
1 Department of Soil Science, Gorgan University of Agricultural Sciences and Natural Resources
2 Department of Soil Science, Gorgan University of Agricultural Sciences and Natural Resources
3 Department of Soil Science, Gorgan University of Agricultural Sciences and Natural Resources
4 Department of civil engineering, Sirjan University of Technology
چکیده [English]

Introduction: Among the micronutrients required by plants, iron deficiency has the maximum limitation for agricultural crops. Iron plays an important role in synthesis of chlorophyll, energy transfer in plants, formation and synthesis of special enzymes, and fixation of nitrogen. Deficiency of iron in plants causes chlorosis or yellowing of young leaves. Iron deficiency is developed due to imbalance of metal ions including copper and manganese, large phosphorus in soil, poor aeration, low temperatures, soil iron deficiency, low organic content, and high concentration of bicarbonate in the root environment. To solve the problem of iron deficiency in plants, very expensive methods are used. Usage of solid wastes of copper melting factories such as slag as soil modifying materials can be useful in iron nutrition. The possibility of using reverb furnace slag of Sarcheshmeh Copper complex as an iron fertilizer was examined in a calcareous soil. Since copper slag contain considerable amount of iron (53.8% iron oxides), therefore, its proper management can solve the problem of iron deficiency in calcareous soils.
Materials and Methods: To investigate the effect of copper slag and organic compounds on iron availability and growth of Sorghum plant, (Speed Feed cultivar), a soil sample was harvested with low soil absorbable iron and organic compound. After air-drying, the soil samples were passed through a 2-mm sieve. Some physiochemical properties of the soil sample used, organic compounds, and the slag were characterized by typical experimental methods. The experimental design was performed as a factorial experiment (copper slag and organic compounds) in a completely randomized design with three replicates. The experimental treatments included five levels of organic compound (pistachio shell and cow manure at two levels of 2% , 4% and the control sample) and 10 levels of iron (copper slag, copper slag with sulfur, copper slag with sulfur and thiobacillus, acidic slag (each at two levels), Fe-EDDHA, and control sample). The experimental treatments were incubated for 3 months. Treatments were then applied to 3 kg samples of soils and the treated samples were incubated in plastic containers at field capacity (FC) moisture content for up to 90 days. At the end of incubation period, 10 sorghum seeds were cultivated in each pot. Foliar application of Fe-EDTA with a concentration of 5 ppm in addition to the mentioned treatments. Harvesting sorghum shoot was performed 90 days after the cultivation. The plant samples were dried for 48 h at 70°C. After digestion of the plant samples by wet oxidation method, concentration of iron, zinc, nickel and cobalt were measured by atomic absorption spectrophotometer. Soil samples were also taken from the pots. After being air-dried, the soil samples were passed through a 2-mm sieve. Amount of electrical conductivity, soluble sodium, concentration of calcium and magnesium as well as iron, zinc, nickel, and cobalt were measured. All statistical analyses were performed using SAS software. Means of different treatments were compared using LSD (P ≤0.05) test.
Results and Discussion: Application of acidic slag increased the soluble sodium and sodium absorption ratio and decreased the soil absorbable iron content. Application of 4 times critical level as slag (S4) increased iron and zinc absorbable by soil, as well as increased concentration of the plant iron. The copper slag with sulfur and thiobacillus developed the maximum absorbable zinc in soil. Comparison of the organic compounds indicated that cow manure has a greater influence on the amount of absorbable iron in soil, iron concentration and uptake by the plant than pistachio shell. On the other hand, with reduction of the concentration of heavy metals, its application is recommended in comparison with pistachio shell. The content of zinc, nickel, and cobalt in the studied plant did not exceed the toxicity level. Heavy metals have low mobility in the soil and are often stabilized by soil colloids or precipitate as different compounds. For this reason, their mobility and transference to shoot diminish.
Conclusion: The slag from copper melting has micro nutrient including iron and zinc. Therefore, it can be concluded that the copper slag has the potential of a source supplying elements for plants. These results confirm the lack of use of acidic treatments. In addition of iron and zinc availability for plants, measurement of other heavy metals in the plant showed that the concentration of measured heavy metals was below their toxicity level. Therefore, suitability of this compound for agriculture will be confirmed. Since addition of heavy metals to soil has various environmental effects, thus repetitive use of slag and its use in large amounts are not recommended. As in absorption of nutrients, immobility in soil, stabilization of metal in the root, and preventing its transference to shoot organs are among the mechanisms of plant when exposed to high concentration of heavy metals, it is suggested that the amount of heavy metals be studied in the root.

کلیدواژه‌ها [English]

  • Copper slag
  • Soil available iron
  • plant iron
  • sorghum