روند تغییرات حفاظت‌کننده‏‌های اسمزی و پارامترهای فیزیولوژی سه گونه اکالیپتوس در پاسخ به تنش سرب

نوع مقاله: علمی- پژوهشی

نویسندگان

1 دکترای اصلاح نباتات، مؤسسه تحقیقات جنگلها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

2 استاد پژوهش، مؤسسه تحقیقات جنگلها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

3 دانشیار پژوهش، مؤسسه تحقیقات جنگلها و مراتع کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران

چکیده

پژوهش پیش‏رو به‌منظور بررسی تغییرات بیوشیمیایی و فیزیولوژیکی نونهال‏های سه گونه اکالیپتوس (Eucalyptus camaldulensis Dehnh.، E. microtheca F. Muell و E. occidentalis Endl.) در پاسخ به سمیت سرب انجام شد. بذرها در گلدان‏های حاوی سنگریزه کشت شدند و توسط محلول‏ غذایی آبیاری شدند. پس از گذشت 10 هفته، نونهال‏های اکالیپتوس در معرض تیمارهای نیترات سرب (صفر، 50، 100 و 200 میلی‌مولار) به ‌مدت 10 ماه قرار گرفتند و پس از آن با استفاده از دستگاه ICP-OES غلظت سرب در اندام‏های ریشه، ساقه و برگ نونهال‏ها اندازه‌گیری شد. روند انباشت سرب در برگ به‌صورت E. camaldulensis > E. microtheca <  E. occidentalis بود. غلظت سرب در بافت ریشه بیشتر از برگ و ساقه بود و در اغلب موارد در بافت ساقه نیز کمتر از برگ بود. در هر سه گونه با افزایش غلظت سرب، غلظت این عنصر در بافت‏های گیاه نیز افزایش یافت. با افزایش غلظت سرب، در هر سه گونه محتوای پرولین و قندهای محلول افزایش یافت و در مقابل محتوای رنگیزه‏ها، محتوای نسبی آب برگ و سطح ویژه برگ کاهش یافت. این نتایج بیان‌گر آن بود که اکالیپتوس دارای مکانیسم‏های مؤثر در برابر سمیت سرب ازجمله تجمع حفاظت‌کننده‏های اسمزی بود. در میان سه گونه مورد بررسی، بیشترین غلظت سرب تجمع‌یافته در برگ و ساقه E. occidentalis مشاهده شد که به‌ترتیب 2/38 و 1/82 برابر غلظت سرب تجمع‌یافته در برگ E.camaldulensis و E. microtheca بود، اگرچه حداقل مقدار شاخص تحمل تنش (0/76) در E. occidentalis مشاهده شد. در کل، با توجه به نتایج به‌دست‌آمده می‏توان اکالیپتوس را به‌عنوان یک گونه مقاوم به فلز سنگین سرب برای گیاه‌پالایی خاک‏‌های آلوده به سرب درنظر گرفت.

کلیدواژه‌ها


عنوان مقاله [English]

Osmoprotectants and physiological responses of three Eucalyptus species to toxic concentrations of lead

نویسندگان [English]

  • Anahita Shariat 1
  • Mohammad Hasan Assareh 2
  • Abbas Ghamari Zare 3
1 Ph.D. Plant Breeding, Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
2 Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
3 Associate Prof., Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
چکیده [English]

One of the serious problems across the world is heavy metal pollution in water bodies that caused by Lead (Pb). This study was designed to find out the effect of Pb toxicity on physiological and biochemical changes in three Eucalyptus species (Eucalyptus camaldulensis Dehnh., E. microtheca F. Muell and E. occidentalis Endl.).Seeds were grown in marble chips and irrigated with nutrient solution. The seedling (42 days old) were exposed to Pb(NO3)2 treatments (Pb:50, 100, 200 mM) for ten months. After this period, leaf, stem and root tissues were harvested. Lead content were determined by ICP-OES and some physiological and morphological characters were determined. The order of Pb accumulation in three species were E. occidentalis> E. camaldulensis> E. microtheca. The concentrations of lead in root tissue were higher than leaf and stem tissue and stem concentration was lower than the concentration of leaf (root Cu>leaf Cu>stem Cu). Tissue concentration increased as Pb increased in three species. The content of prolin, soluble sugar raised by increasing metal concentrations, but the content of pigments, relative water content and specific leaf area decreased. These results suggest that eucalypts have efficient mechanism to tolerate Pb toxicity, as evidenced by accumulating of osmoprotectants. Comparison of three Eucalyptus species revealed that E. occidentalis had the highest concentrations of Pb in the leaves and stems. Accumulation of Pb in the E. occidentalis leaves was 2.38 and 1.82 times more than E. microtheca and E.camaldulensis respectively. Although the least amount of stress tolerance index (0.76) was observed in E. occidentalis. In general, the results showed that Eucalypts could be considered as a tolerant species for hyperaccumulation of lead and phytoremediation of contaminated soil by lead.

کلیدواژه‌ها [English]

  • Heavy metal toxicity
  • phytoremediation
  • pigments
  • prolin
  • Soluble sugar
- Ahmad, P., Sharma, S. and Srivastava, P.S., 2006. Differential physio-biochemical responses of high yielding varieties of Mulberry (Morus alba) under alkalinity (Na2CO3) stress in vitro. PhysiologyandMolecular BiologyofPlants, 12: 59-66.

- Amini, M., Afyuni, M., Khademi, H., Abbaspour, K.C. and Schulin, R., 2005. Mapping risk of cadmium and lead contamination to human health in soils of central Iran. Science of the Total Environment, 347(1-3): 64-77.

- Assareh, M.H., Shariat,A. and Ghamari Zare, A., 2008. Seedling response of three Eucalyptus species to toxic concentration of copper and zinc in solution culture. Caspian Journal of Environmental Science, 6(2): 97-103.

- Bates, I.S., Waldern, R.P. and Teare, I.D., 1973. Rapid determination of free prolin for water stress studies. Plant and Soil, 39: 205-207.

- Beadle, C.L., 1993. Growth analysis: 36-46. In: Hall, D.O., Scurelock, J.M.O., Bolhar-Nordenkampf, H.R., Leegood, R.C. and Long, S.P. (Eds.). Photosynthesis and Production in a Changing Environment: A Field and Laboratory Manual. Springer Netherlands, Netherlands, 477p.

- Douay, F., Pelfrêne, A., Planque, J., Fourrier, H., Richard, A., Roussel, H. and Girondelot, B., 2013. Assessment of potential health risk for inhabitants living near a former lead smelter, part 1: metal concentrations in soils, agricultural crops, and homegrown vegetables. EnvironmentalMonitoring and Assessment, 185: 3665-3680.

- Ekmekci, Y., Tanyolac, D. and Ayhan, B., 2009. A crop tolerating oxidative stress induced by excess lead: maize. Acta Physiologia Plantarum, 31: 319-330.

- El-Khatib, A. and Faheed, F.A., 2015. Physiological response of Eucalyptus rostorata to heavy metal air pollution. El-Minia Science Bulletin, 15(2): 429-451.

- Fernandez, G., 1992. Effective selection criteria for assessing plant stress tolerance. Proceedings of the International Symposium on Adaptation of Vegetables and Other Food Crops in Temperature and Water Stress. Tainan, Taiwan, 13-18 Aug. 1992: 257- 277.

- Fine, P., Paresh, R., Beriozkin, A. and Hass, A., 2014. Chelant-enhanced heavy metal uptake by Eucalyptus trees under controlled deficit irrigation. Science of the Total Environment, 493: 995-1005.

- Hendry, G.A.F. and Wallace, R.K., 1993. The origin, distribution and evolutionary significance of fructans: 119-139. In: Suzuki, M. and Chatterton, J.N. (Eds.). Science and Technology of Fructans. CRC Press, Boca Raton, 384p.

- Hunt, R., 1990. Basic Growth Analysis: Plant Growth Analysis for Beginners. Unwin Hyman Publisher, London, 112p.

- Irigoyen, J.J., Einerich, D.W. and Sanchez-Diaz, M., 1992. Water stress induced changes in concentrations of prolin and total soluble sugars in nodulated alfalfa (Medicago sativa) plants. Physiologia Plantarum, 84(1): 55-60.

- Krasensky, J. and Jonak, C., 2012. Drought, salt, and temperature stress-induced metabolic rearrangements and regulatory networks. Journal of Experimental Botany, 63: 1593-1608.

- Levy, D.B., Redente, E.F. and Uphoff, G.D., 1999. Evaluating the phytotoxicity of Pb-Zn tailings to big bluestem (Andropogon gerardii vitman) and swichgrass (Panicum virgatum L.). Soil Science, 164(6): 363-375.

- Malar, S., Shivendra Vikram, S., Favas, P.J.C. and Perumal, V., 2014. Lead heavy metal toxicity induced changes on growth and antioxidative enzymes level in water hyacinths [Eichhornia crassipes (Mart.)]. Botanical Studies, 55(54): 1-11.

- Moor, R.H., 1960. Laboratory Guide for Elementary Plant Physiology. Burgess Publication, Minneapolis, 144p.

- Nazir, R., Khan, M., Masab, M., Rehman, H.U., Rauf, N.U., Shahab, S. and Shaheen, Z., 2015. Accumulation of heavy metals (Ni, Cu, Cd, Cr, Pb, Zn, Fe) in the soil, water and plants and analysis of physicochemical parameters of soil and water collected from Tanda Dam Kohat. Journal of Pharmaceutical Sciences and Research, 7(3): 89-97.

- Ncube, E. and Phiri, B., 2015. Concentrations of heavy metals in Eucalyptus and Pinus wood sawdust and smoke, Copperbelt province, Zambia. Maderas, Ciencia Y Tecnología, 17(3): 585-596.

- Pelfrêne, A., Waterlot, C. and Douay, F., 2013. Influence of land use on human bioac-cessibility of metals in smelter-impacted soils. Environmental Pollution, 178: 80-88.

- Piotrowska, A., Bajguz, A., Godlewska, B., Czerpak, R. and Kaminska, M., 2009. Jasmonic acid as modulator of lead toxicity in aquatic plant Wolffia arrhiza (Lamnaceae). Environmentaland Experimental Botany, 66: 507-513.

- Rivas Ubach, A., 2013. Stoichiometric and metabolomic shifts of organisms under environmental changes. Ph.D. thesis, Autonomous University of Barcelona, Barcelona, 394p.

- Rosen, C.J., 2002. Lead in the home garden and urban soil environment (Report). Published by University of Minnesota Extension, Minnesota, 4p.

- Shabanian,  N. and Cheraghi, Ch., 2013. Comparison of phytoremediation of heavy metals by woody species used in urban forestry of Sanandaj city. Iranian Journal of Forest and Poplar Research, 21(1): 154-165 (In Persian).

- Shariat, A. and Assareh, M.H., 2008. Effects of drought stress on pigments, prolin, soluble sugar and growth parameters on four Eucalyptus species. Pajouhesh & Sazandegi, 78: 139-148 (In Persian).

- Shariat, A. and Assareh, M.H., 2009. Effects of drought stress on Eucalyptus camaldulensis at germination and seedling stage: 244-254. In: Kharazipour, A.R., Schöpper, Ch., Müller, C. and Euring, M. (Eds.). Review of Forests, Wood Products and Wood Biotechnology of Iran and Germany (Part 3). Published by University of Goettingen, Goettingen, 329p.

- Sharma, P. and Dubey, R.S., 2005. Lead toxicity in plants. Brazilian JournalofPlant Physiology, 17: 35-52.

- Voleníková, M. and Tichá, I., 2001. Insertion profiles in stomatal density and sizes in Nicotiana tabacum L. plantlets. Biologia Plantarum, 44: 161-165.

- Watson, D.J., 1952. The physiological basis of variation in yield. Advanced Agronomy, 4: 101-145.

- Westerman, R.L., 1990. Soil Testing and Plant Analysis. Soil Science Socity of America Press, Madison, 571p.