بهبود صفات فیزیولوژیکی و بیوشیمیایی سورگوم علوفه‌ای (Sorghum bicolor L.) با کابرد بیوچار و اسید سالیسیلیک در خاک آلوده به فلز سنگین سرب

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه زراعت، دانشگاه علوم کشاورزی و منابع طبیعی ساری

2 دانش آموخته دکتری گروه زراعت، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، مازندران، ایران

چکیده

سابقه و هدف: پژوهش حاضر به‌منظور بررسی اثر بیوچار و اسید سالیسیلیک بر تغییرات فیزیولوژی و بیوشیمیایی سورگوم در شرایط تنش سرب انجام شد.
مواد و روش‌ها: این آزمایش به‌صورت فاکتوریل در قالب طرح کاملا تصادفی با 4 تکرار به صورت گلخانه ای در سال 1398 انجام شد. تیمارهای این آزمایش شامل پنج سطح سرب (0، 400، 800، 1200 و 1600 میلی‌گرم سرب در کیلوگرم خاک از منبع نیترات سرب)، دو سطح بیوچار (عدم مصرف و مصرف بیوچار 20 گرم بیوچار به ازای هر کیلوگرم خاک) و دو سطح اسید سالیسیلیک (شامل عدم محلول‏پاشی و محلول‏پاشی‌ 2 میلی‌مولار اسید سالیسیلیک) بود.
یافته‌ها: نتایج نشان داد که مصرف بیوچار و اسید سالیسیلیک به‌ترتیب باعث افزایش 25/5 و 81/4 درصدی کلروفیلa شد. بیشترین میزان کاروتنوئید در تیمار تلفیقی مصرف بیوچار و محلول‌پاشی اسید سالیسیلیک به‌دست آمد. با افزایش سطوح سرب میزان فنل افزایش یافت که این افزایش در گیاهانی که با اسید سالیسیلیک محلول‌پاشی شده بودند بیشتر بود. همچنین میزان فلاونوئید تحت تأثیر مصرف بیوچار 57/10 درصد افزایش نشان داد. برهمکنش بیوچار و اسید سالیسیلیک باعث افزایش 48/88 درصدی پرولین نسبت به شاهد بود.
نتیجه‌گیری: نتایج تحقیق حاضر بیانگر تأثیر منفی تنش سرب بر رشد سورگوم و همچنین اثرات مثبت و معنی‌دار اسید سالیسیلیک و بیوچار بر ویژگی‌های این گیاه بود. لذا استفاده از این مواد ارزان و قابل دسترس در خاک می‌تواند یک روش مناسب و مقرون به صرفه برای کاهش آلودگی خاک بوده تا ضمن افزایش فعالیت‌های متابولیک گیاه سورگوم، مقاومت گیاه را در برابر تنش سرب بهبود بخشد.

کلیدواژه‌ها


عنوان مقاله [English]

Improvement of Physiological and Biochemical Traits of Sorghum (Sorghum bicolor L.) by Application of Biochar and Salicylic Acid in Soils Contaminated with Lead Heavy Metal

نویسندگان [English]

  • Seyedeh Asieh Jalali 1
  • Faezeh Zaefarian 1
  • roghayeh hasanpour 2
  • Arastoo Abbasian 1
1 Department of Agronomy, Sari Agricultural Sciences and Natural Resources University
2 Graduated Ph.D Student of Agronomy, Department of Agronomy, Sari Agricultural Sciences and Natural Resources University, Sari, Mazandaran, Iran
چکیده [English]

Background and objectives: This study was to investigate the effect of biochar and salicylic acid on sorghum (Sorghum bicolor var.Speed feed) physiological and biochemical changes under lead stress conditions
Materials and methods: The experiment was carried out as a factorial experiment in a completely randomized design with 4 replications in greenhouse in 2019. The treatments of this experiment include five levels of lead (0, 400, 800, 1200 and 1600 mg of lead per kg of soil from lead nitrate source), two levels of biochar (no consumption and consumption of biochar 20 g of biochar per kg of soil) and two levels of acid salicylic acid (including non-foliar and 2 mM salicylic acid foliar).
Results: The results showed that consumption of biochar and salicylic acid increased chlorophyll a by 5.25 and 4.81%, respectively. The highest amount of carotenoids was obtained in the combined treatment of biochar consumption and salicylic acid foliar application. Phenol levels increased with increasing lead levels, which was greater in plants sprayed with salicylic acid. Also, the amount of flavonoids increased by 10.57% under the influence of biochar consumption. The interaction of biochar and salicylic acid increased proline, and this increase was 88.48% compared to the control.
Conclusion: Therefore, the use of these cheap and available materials in the soil can be a suitable and cost-effective method to reduce soil contamination to increase the metabolic activity of sorghum plant, improve plant resistance to lead stress.

کلیدواژه‌ها [English]

  • Chlorophyll
  • heavy metals
  • sorghum
  • biochemical
  • antioxidant activity
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