Does excess boron affect the malondialdehyde levels of potato cultivars?

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1 EurAsian Journal of BioSciences Eurasia J Biosci 7, (2013) Does excess boron affect the malondialdehyde levels of potato cultivars? Muavviz Ayvaz 1*, Murat Kemal Avci 1, Cigdem Yamaner 1, Mesut Koyuncu 2, Avni Guven 3, Kurt Fagerstedt 4 1 Adnan Menderes University, Department of Agricultural Biotechnology, Aydin, Turkey 2 Department of Biology, Faculty of Science and Letters, Gaziosmanpasa University 60250, Tokat, Turkey 3 Department of Biology, Faculty of Science, Ege University 35100, Izmir, Turkey 4 Department of Biosciences, Viikki Biocenter, University of Helsinki FI-00014, Helsinki, Finland *Corresponding author: mayvaz@yahoo.com Abstract Background: Malondialdehyde (MDA) is a product of lipid peroxidation and a sign of oxidative stress in plants. Therefore, determining the responses of plants to a particular type of stress at a particular time will shed a light on clarifying the stress status of the plants. In this study, we report how the MDA levels in potato cultivars changed with toxic concentrations of boron, an essential plant micronutrient. Material and Methods: Eight different potato (Solanum tuberosum) cultivars (cv. Konsul, cv. Morene, cv. Slaney, cv. Mona Lisa, cv. Jaerla, cv. Poroventa, cv. Yayla Kizi, and cv. Armada) were used as study material. Excess boron was applied for seven weeks in three concentrations (0.5, 2.5 and 5 mm) to plants that were grown from tubers. Plants were harvested and a malondialdehyde content analyses was carried out using leaf tissues. Results: The MDA levels in cv. Mona Lisa and Yayla Kizi with excess boron steadily increased with increasing concentrations in all the groups, compared to the control group. In cv. Morene, the MDA decreased in the 0.5 mm boron application and increased in the 2.5 and 5 mm boron applications. In cv. Armada, cv. Slaney, cv. Konsul, and cv. Poroventa, the MDA levels fluctuated in the different groups of each cultivar. In cv. Jaerla, the MDA decreased in all groups with an increase in boron, compared to the control group. Conclusions: The MDA levels with excess boron showed an increase, fluctuation, and decrease in each group of the cultivars, compared to the control group. Therefore, the MDA levels in potato plants with excess boron might not be a clear sign to determine the level of stress. This is the first report of MDA levels in eight different potato cultivars subjected to three different excess boron concentrations. Keywords: Boron toxicity, malondialdehyde, Solanum tuberosum, stress physiology. Abbreviations: MDA: Malondialdehyde; B: Boron. Ayvaz M, Avci MK, Yamaner C, Koyuncu M, Guven A, Fagerstedt K (2013) Does excess boron affect malondialdehyde levels of potato cultivars? Eurasia J Biosci 7: EurAsian Journal of BioSciences INTRODUCTION Boron is an essential micro element for plant growth and development (Warington 1923). On the other hand, toxicity and shortage range are very narrow in plants (Gupta et al. 1985). Excess boron may naturally occur in soil or as a result of overirrigation with water rich in boron. Evaporation of groundwater that reaches the top soil capillary might be a reason of boron toxicity in arid and semiarid regions. High boron levels in soils are found in Iraq, Egypt, Jordan, Syria, Morocco, Turkey, Chile, California, and South Australia (Landi et al. 2012). Weathering of minerals, rain-wash of mining wastes, seawater intrusion, geothermal, and volcanic processes significantly contribute to the natural occurence of boron in the environment (Moore 1991). In the Great Menderes River Basin, Turkey, the injection of geothermal wastewater into irrigation water causes boron toxicity in the region. The boron content of some small sized rivers feeding the Great Menderes might reach 21.1 mg/l (ppm) boron. In the long term, this causes accumulation and may lead to desertification of soils (Aydin and Seferoglu 1999). Bolca et al. (2010) investigated the intrusion effect of geothermal sources in the Alangullu region and reported high Received: April 2013 Accepted: May 2013 Printed: June

2 concentrations of boron in water resources, agricultural land soils, and in plants. Excess boron in potato crop production may reduce yield and quality. Potato production in Turkey ranks thirteenth worlwide and second in the middle east after Iran (Anonymous 2011). When plants are exposed to different type of stresses such as boron toxicity, they present different defence mechanisms to be able to maintain their homeostasis, which is a result of their genetic characteristics (Nable and Paull 1991, Paull et al. 1992, Karabal et al. 2003).Cereals, herbaceous plants, strawberry, and potatoes require less than 0.1 ppm B, tomatoes, cotton, carrot, onion, cucumber, tobacco, and some fruit tress require ppm B, whereas, mint, apple, cabbage, beets, and alfalfa require more than 0.5 ppm B (Kovanci 1979). Antioxidative enzymes and antioxidant systems are an example of defence mechanisms to alleviate the effects of oxidative stresses (Mittler 2002). Malondialdehyde (MDA), is a product of lipid peroxidation, is accepted to be one of the simplest signs of oxidative stress in organisms (Zhang and Kirkham 1996). In previous studies, the MDA levels showed fluctuations in different plant species subjected to excess boron. On the other hand, in some cases increasing stress caused fluctuations in the MDA levels. Therefore, the aim of this study is to investigate the MDA levels in different potato cultivars subjected to excess boron and to determine whether MDA levels might be a sign of boron toxicity stress in potato plants. This is the first report to announce the MDA levels in eight different potato cultivars and to determine whether the MDA levels will be a clear sign of the stress levels in plants subjected to excess boron. MATERIALS AND METHODS Plant material and growth conditions Eight different certified potato (Solanum tuberosum) cultivars, (cv. Konsul, cv. Morene, cv. Slaney, cv. Mona Lisa, cv. Jaerla, cv. Poroventa, cv. Yayla Kizi, and cv. Armada) were provided by the Aegean Agricultural Research Institute (AARI). Potato tubers were grown in quartz sand ( mm. SP-Minerals Oy, Nilsiän kvartsi, Finland (Chemical composition of the quartz sand: SiO2 (99.4%), Al2O3 (0.2%), Fe2O3 (0.02%), and K2O (0.04%)) in a green house. Plants were grown in plastic pots (Soparco, code 6820, cm (diameter height) with a volume of 2 L) and were irrigated with a Hoagland and Arnon (1950) nutrient solution for 7 w. Illumination was provided by 400 W highpressure sodium lamps (Lucalox, LU 400/HO/T/40NG) for 16 h day -1. Daytime humidity was 50% and the temperature was 20 C (day) and 16 C (night). Boron treatment Boron was applied 32 days after planting the tubers in three different concentrations (0.5, 2.5, and 5 mm). The plants were then harvested at the end of the 15 days of excess boron application. Determination of lipid peroxidation The lipid peroxidation was measured according to Rubin et al. (1976) where the amount of malondialdehyde (MDA), the product of lipid peroxidation, was estimated with the thiobarbituric acid reaction method. The leaves (0.1 g) were homogenized in 3 ml of 0.05 M Tris-HCl buffer with a ph 7.4. After filtration and centrifugation (20 min at 13,200 rpm), thiobarbituric acid (0.5% [w/v] in 20% [w/v] TCA) was added to an aliquot of the supernatant and the mixture and then heated in a boiling water bath (over 90 C) for 30 min. After cooling and centrifugation (20 min at 13,200 rpm), the absorbance of the supernatant was measured at 532 nm and corrected for non-specific turbidity by subtracting the absorbance at 600 nm. A solution of 0.5% Thiobarbituric acid [w/v] in 20% [w/v] TCA was used as a blank. The amount of MDA was calculated per gram fresh weight by using the malondialdehyde extinction coefficient of μm -1 cm -1. Statistical analysis All experiments were designed in a completely randomized block. Comparisons among the means were performed using the Duncans Multiple Range test. The means in the figures accompanied by different letters are significantly different at P

3 RESULTS The MDA level changes under boron toxicity were examined in eight different potato cultivars grown in Turkey. Compared to the control, the MDA steadily increased with increasing concentrations in cv. Mona Lisa and Yayla Kizi. In Yayla Kizi, the increase was statistically significant. In cv. Morene, the MDA decreased at 0.5 mm boron and increased at 2.5 and 5 mm boron applications significantly, compared to the control. In cv. Armada, at 0.5 and 2.5 mm boron application, the MDA decreased and then increased at 5 mm boron application, compared to the control. In cv. Slaney, the MDA increased at 0.5 mm and decreased at 2.5 mm, then increased at a 5 mm boron application significantly, compared to the control. In cv. Konsul, the MDA decreased at 0.5 mm boron and at 2.5 mm B remained almost stable, then decreased at 5 mm B, compared to the control. In cv. Poroventa, the MDA decreased sharply and remained stable at 2.5 and 5 mm boron, compared to the control. In cv. Jaerla, the MDA decrease was statistically significant in all groups with an increase in boron, compared to the control (Table 1, Fig. 1). DISCUSSION Malondialdehyde (MDA), is a product of lipid peroxidation, and is accepted to be one of the simplest signs of oxidative stress in organisms (Zhang and Kirkham 1996, Mittler 2002). With excess boron toxicity, the MDA levels in the leaf tissues of barley (Karabal et al. 2003), pear leaves (Wang et al. 2011), Vitis vinifera (Gunes at al. 2006), apple rootstocks (Molassiotis et al. 2006), and tomatos (Cervilla et al. 2007) increased compared to the control (Table 2). In our results, the MDA levels in cultivar Yayla Kizi increased significantly in all groups, compared to the control. Moreover, in a study with two different chickpea cultivars with excess boron toxicity, the MDA content increased in one cultivar and did not change significantly in the another (Ardic et al. 2009). On the other hand, excess boron increased the thiobarbituric acid reactive substance (TBARS) content in Artemisia annua L. (Aftab el al. 2010) and citrus (Han et al. 2009). However, in tomatos with excess toxic boron, the TBARS at the first harvest increased but, did not change at the second harvest, compared to the control (Ferro et al. 2010). In another study with lettuce, the boron toxicity alone did not show significant effect on the MDA levels (Eraslan et al. 2007). In contrast with previous MDA level results, cv Monalisa, Armada, and Konsul did not change significantly among the different excess boron groups in our study. In a study with Pisum sativum, of plants harvested on the 3 rd and 7 th day after the toxic boron treatment, the MDA levels increased and then decreased respectively (Hamurcu et al. 2012). In additon to that, the 7 th day harvested plants showed fluctuations in the MDA levels among the different boron application groups. In another study, with two Triticum durum cultivars and Puccinellia distans, the plants were harvested at two different times to determine the level of changes between days. In this study, the MDA levels also fluctuated (increased and decreased) among the groups and within the groups (Hamurcu et al. 2009) In our study, the MDA levels in cv. Poroventa and Jaerla decresaed significantly compared to the control, in line with the Hamurcu et al. (2009, 2012) s results. However, in cv Slaney, the MDA showed fluctuations in the different excess boron application groups of the cultivar as in Hamurcu et al. (2009, 2012). Previous studies showed that in some cases the MDA levels increased steadily with increasing stress. On the other hand, increasing stress caused fluctuations in the MDA levels in some cases. This fluctuation can be explained by the instant metabolite and pathway shifts of enzymatic and non-enzymatic detoxification mechanisms. Since the MDA levels in the same species changed at different sampling times (Ferro et al. 2010, Hamurcu et al. 2009, 2012), it is thought that the sampling time and frequency plays a crucial role for explaining the proper level of the stress and defence mechanism. Our results showed that the duration of stress exposure, sampling time and frequency, and type of tissue may help to explain the change of the MDA 49

4 Table 1. Effect of boron toxicity on the MDA levels in eight different potato cultivars (±S.E.M.). Different letters in each row represent significant differences at P<0.05 level, based on the Duncan s multiple range test. S.E.M.= Standart Error of the Mean *Values in parentheses indicate percent of control. Table 2. Summary of previous studies of the MDA level changes with boron toxicity in various species. Fig. 1. Effect of boron toxicity on the MDA levels in eight different potato cultivars. levels in plants. In conclusion, the MDA levels in each group of the cultivars with excess boron showed an increase, fluctuation, and decrease, compared to the control. Therefore, the MDA levels in the potato plants with excess boron might not be a clear sign of stress levels. In order to explain the cause and effect relation of the MDA level fluctuations in plant species, extensive future studies are needed. This is : Increase, : Increase and decrease, : No difference the first report of the MDA levels in eight different potato cultivars subjected to three different excess boron concentrations. REFERENCES Aftab T, Khan MMA, Idrees M, Naeem M, Ram M (2010) Boron Induced Oxidative Stress, Antioxidant Defence Response and Changes in Artemisinin Content in Artemisia annua L. Journal of Agronomy and Crop Science 196: Anonymous (2011) Agricultural Production Statistics. Food and Agriculture Organization of the United Nations Statistics (FAOSTAT), Rome. (Date accessed ) Ardic M, Sekmen AH, Tokur S, Ozdemir F, Turkan I (2009) Antioxidant responses of chickpea plants subjected to boron toxicity. Plant Biology 11: Aydin G, Seferoglu S (1999) Aydin Yoresinde Kullanilan Bazi Sulama Sularinin Bor Konsantrasyonlarinin Bitki Beslemesi ve Toprak Kirliligi Acisindan Incelenmesi. TOGTAG-1767 Project Final Report. Turkiye Bilimsel ve Teknik Arastirma Kurumu, Ankara. 50

5 Bolca M, Kilinc R, Altinbas U, Sac MM; Kumru MN, Esetlili-Colak B, Esetlili MT, Ozen F (2010) Alangullu (Aydin) Bolgesindeki Jeotermal Kaynaklarin Kimyasal Ozelliklerinin ve Icerdikleri Radyoaktif Maddelerin Su Kaynaklari, Tarim Topraklari ve Kultur Bitkilerine Etkilerinin Multidisipliner Yaklasimla Saptanmasi Uzerine Arastirmalar. TOVAG-107O085 Project Final Report, Turkiye Bilimsel ve Teknik Arastirma Kurumu, Ankara. Cervilla LM, Blasco BA, Rios JJ, Romero L, Ruiz JM (2007) Oxidative stress and antioxidants in tomato (Solanum lycopersicum) plants subjected to boron toxicity. Annals of Botany 100: Eraslan F, Inal A, Savasturk O, Gunes A (2007) Changes in antioxidative system and membrane damage of lettuce in response to salinity and boron toxicity. Scientia Horticulturae 114(1): Ferro M, Sgherri C, Romani M, Carvalho MF, Izzo R (2010) Tomato irrigated with boron enriched fresh water: effects on leaves and berries. Agrochimica 6: Gunes A, Soylemezoglu G, Inal A, Bagci EG, Coban S, Sahin O (2006) Antioxidant and stomatal responses of grapevine (Vitis vinifera L.) to boron toxicity. Scientia Horticulturae 110: Gupta UC, Jame YW, Campbell CA, Leyshon JA, Nicholaichuck W (1985) Boron toxicity and deficiency: A review. Canadian Journal of Soil Science 65: Hamurcu M, Demiral T, Hakki EE, Tamkoc A, Ozdemir C, Ersoy N (2012) Farklı Bor Dozlarinin Bezelye Hatlarının Temel Fizyolojik, Biyokimyasal ve Anatomik Ozellikleri Uzerine Etkisinin Belirlenmesi. TOVAG-110O527 Project Final Report, Turkiye Bilimsel ve Teknik Arastirma Kurumu, Ankara. Hamurcu M, Gezgin S, Turkan I, Hakki E, Soylu S, Yorgancilar M (2009) Makarnalik Bugday Cesitleri (Triticum durum) ile Corak Cimi'nde (Puccinellia distans) Bor Toksisitesinin Temel Fizyolojik ve Biyokimyasal Ozelliklere Etkisinin Belirlenmesi. TOVAG-108O559 Project Final Report, Turkiye Bilimsel ve Teknik Arastirma Kurumu, Ankara. Han S, Tang N, Jiang HX, Yang LT, Li Y, Chen LS (2009) CO 2 assimilation, photosystem II photochemistry, carbohydrate metabolism and antioxidant system of citrus leaves in response to boron stress. Plant Science 176: Hoagland DR, Arnon DI (1950) The water-culture method for growing plants without soil. California Agricultural Experiment Station Circular 347: Karabal E, Yücel M, Hüseyin AÖ (2003) Antioxidant responses of tolerant and sensitive barley cultivars to boron toxicity. Plant Science 164: Kovanci I (1979) Ic Ege Bölgesi Sulama Sularının Bitki Beslemesi Açısından Kimi Nitelikleri ve Kimyasal İçerikleri Üzerine Bir Araştırma. No: 364, Ege Üniversitesi, Ziraat Fakultesi Yayini, Izmir. Landi M, DeglInnocenti E, Pardossi A, Guidi L (2012) Antioxidant and Photosynthetic Responses In Plants Under Boron Toxicity: A Review. American Journal of Agricultural and Biological Sciences 7(3): Mittler R (2002) Oxidative stress, antioxidants and stress tolerance. Trends in Plant Science 7(9): Molassiotis A, Sotiropoulos T, Tanou G, Diamantidis G, Therios I (2006) Boron induced oxidative damage and antioxidant and nucleolytic responses in shoot tips culture of the apple rootstock EM9 (Malus domestica Borkh). Environmental and Experimental Botany 56: Moore JW (1991) Inorganic Contaminants of Surface Water: Research and Mining Priorities. 1 st Edition, Sringer Verlag, New York. Nable RO, Paull JG (1991) Mechanism of Genetics of Tolerance to Boron Toxicty in Plants. Current Topics in Plant Biochemistry and Physiology 10: Paull JG, Nable RO, Lake AWH, Materne MA, Rathjen A J (1992) Response of Annual Medics (Medicago spp.) and Field Peas (Pisum sativum) to High Concentration of Boron: Genetic Variation and The Mechanism of Tolerance. Australian Journal of Agricultural Research 43:

6 Rubin BA, Merzlyak MN, Juferova SG (1976) Oxidation of lipid components in isolated chloroplasts under lighting. The substrates and products of lipid peroxidation. Fiziologiya Rasteniy 23: (In Russian) Wang JZ, Tao ST, Qi KJ, Wu, Wu HQ, Zhang SL (2011) Changes in photosynthetic properties and antioxidative system of pear leaves to boron toxicity. African Journal of Biotechnology 10(85): Warington K (1923) The Effect of boric acid and borax on the broad bean and certain other plants. Annals of Botany 37: Zhang HX, Kirkham MB (1996) Lipid Peroxidation in Sorghum and Sunflower Seedlings as Affected by Ascorbic Acid, Benzoic Acid, and Propyl Gallate. Journal of Plant Physiology 149(5):

7 Aşırı Bor, Patates Çeşitlerinde Malondialdehit Miktarlarını Etkiler mi? Özet Giriş: Malondialdehit (MDA) bitkilerde oksidatif stresin bir göstergesi ve lipit peroksidasyonunun bir ürünüdür. Buradan hareketle bitkilerin belirli bir zamanda belirli bir stres türüne vermiş olduğu tepkiler bitkinin stres seviyesi hakkında bilgi sahibi olmamızı sağlar. Bu çalışmada patates çeşitlerinin bitkiler için gerekli bir mikro besin elementi olan borun toksik konsantrasyonlarına maruziyeti sonrası MDA miktarı değişimleri incelenmiştir. Materyal ve Metot: Sekiz farklı patates (Solanum tuberosum) kültür çeşidi (cv. Konsul, cv. Morene, cv. Slaney, cv. Mona Lisa, cv. Jaerla, cv. Poroventa, cv. Yayla Kizi, ve cv. Armada) çalışmada materyal olarak kullanılmıştır. Aşırı bor, yumrulardan yetiştirilen patateslere, yedi hafta boyunca üç farklı konsantrasyonda (0,5, 2,5 ve 5 mm) uygulanmıştır. Bitkiler hasat edilerek yaprak dokularında malondialdehit miktarı analizleri gerçekleştirilmiştir. Bulgular: cv. Mona Lisa ve Yayla Kizi çeşitlerinde artan bor konsantrasyonlarındakontrole göre tüm uygulama gruplarında MDA miktarları artış göstermiştir. Morene çeşidinde MDA miktarı 0,5 mm bor uygulaması ile azalmış, 2,5 mm ve 5 mm bor uygulamasında artış göstermiştir. Artan bor konsantrasyonunda MDA miktarları kontrole göre cv. Armada, cv. Slaney, cv. Konsul, ve cv. Poroventa da her bir uygulama grubunda düzenli olmayan artış ve azalış (dalgalanma) göstermiştir. Jaerla çeşidinde ise MDA miktarı artan bor konsantrasyonuna paralel olarak tüm uygulama guruplarında kontrole göre azalma göstermiştir. Sonuç: MDA miktarları artan bor konsantrasyonlarında, her bir çeşidin her bir uygulama grubunda kontrol gruplarına göre; artan, dalgalı ve azalan bir miktar değişimi göstermiştir. Patates çeşitlerinde MDA miktarları bitkinin artan bor konsantrasyonlarında bitkinin stres seviyesini belirlemede yeterli bir ölçüt olamayabilir. Aşırı üç farklı bor konsantrasyonunda, MDA miktarları değişimini inceleyen bu çalışma sekiz farklı patates çeşidi için bir ilktir. Anahtar Kelimeler: Bor toksistesi, malondialdehit, Solanum tuberosum, stres fizyolojisi. 53