نوع مقاله : فنی ترویجی

نویسندگان

1 دانشجوی دکتری گروه علوم و مهندسی خاک دانشکده کشاورزی دانشگاه تبریز، تبریز، ایران.

2 دانشیار گروه علوم و مهندسی خاک دانشکده کشاورزی دانشگاه تبریز، تبریز، ایران

چکیده

 
ورود نانوفناوری به عرصه­های مختلف علمی و صنعتی، دستاوردهای نوینی را ایجاد کرده است. این فناوری با کوچک کردن اندازه مواد موجب بروز ویژگی‌هایی از آنها می­شود که قبلاً وجود نداشت یا محسوس نبود. هرچند نانوفناوری موجب بهبود برخی ویژگی­های کودها شده است و بررسی‌های متعددی اثرهای مثبت آنها را در گیاهان مختلف گزارش کرده­اند اما باید متذکر شد که اکثر این بررسی‌ها آزمایشگاهی بوده و مدت رشد گیاهان بسیار کوتاه در نظر گرفته شده و در بسیاری از موارد نیز تنها به جوانه­زنی بذرها اکتفا شده است. به­علاوه، گزارش‌های زیادی نیز وجود دارند که پی‌آمدهای مصرف نانومواد را در گیاهان نشان می­دهند. برای مثال، نانوذرات عناصری همچون آلومینیم، آهن، روی، تیتانیم، نیکل و نقره، نانوذرات هیدورکسی آپاتیت و نانو لوله­های کربنی در گیاهان پیاز، ماش، چچم، برنج، لوبیا، ذرت، خیار، سورگوم و گوجه­فرنگی موجب کاهش رشد شده است. بنابراین، لازم است قبل از استفاده از نانومواد به‌عنوان کود، پژوهش‌های کاملی از تعامل آنها با گیاهان و سرنوشت نهایی این مواد در گیاه و زنجیره غذایی انجام شود. از طرف دیگر، چون گیاهان در ابتدای زنجیره غذایی قرار دارند ورود و تجمع نانومواد به داخل آنها، می­تواند موجب ورود نانومواد به زنجیره غذایی شده و نانومواد را به سطوح بالاتر این زنجیره و به‌ویژه انسان­ها انتقال دهد. این مقاله به بررسی اثر غلظت­های زیاد نانومواد بر رشد برخی گیاهان، آسیب­های ناشی از آنها و نیز توان جذب و انباشتگی نانوذرات توسط گیاهان می­پردازد.

کلیدواژه‌ها

عنوان مقاله [English]

Effects of Nanomaterial Overdose in Plant Nutrition

نویسندگان [English]

  • mohammadreza maghsoudi 1
  • nosratollah najafi 2

1 PhD Student, Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

2 Associate Professor, Department of Soil Science, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

چکیده [English]

 
The advent of nanotechnology has led to new achievements in the different fields of science and technology. The minified size of materials under this technology discloses certain novel or hitherto ignored features and properties of these materials. It is true that nanotechnology has helped enhance certain features of fertilizers as evidenced by a number of studies reporting their positive effects on different plants. However, it should be noted that most of these studies were performed under laboratory conditions and considered only short periods of plant life, in many cases only up to germination. This is while there are many reports showing the adverse consequences of using nano-materials. For example, nanoparticles of aluminum, iron, zinc, titanium, nickel, and silver or hydroxyapatite nanoparticles and carbon nanotubes have caused reduced growth in onions, vetch, rye, rice, beans, corn, cucumber, sorghum, and tomato plants. These inconsistent reports call for exhaustive investigations to determine the interactions between nano-materials and plants and their final fate in the plant and food chain before they can be used as fertilizers. Since plants stand at the beginning of the food chain, introduction and accumulation of nano-materials inside them might help transfer these materials to higher levels of the chain to end up in the human body. This paper studies the effects of high concentrations of nano-materials on plant growth in certain species, the associated damages, and the uptake and accumulation of nanoparticles in plant.

کلیدواژه‌ها [English]

  • Food chain
  • Nano-fertilizer
  • Nanotechnology
  • Plant nutrition
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