Abstract

1. Anatomical Study of TyphaangustifoliaL. Root Grown in Acid Mine Drainage (AMD) at Ex-Mamut Copper Mine, Ranau Lo Vun Yen, KartiniSaibeh, and Harry Chong Lye Hin Institute of Biology Tropical and Conservation, Universiti Malaysia Sabah. PH CW EN CW X EN PH PH X CW Conclusion Abstract Methods EP EX EP EP 50µm C 50µm A EX Anatomical changes of Typhaangustifoliarootis due to response from heavy metals found in acid mine drainage. The influence of heavy metals might cause changes in this plant’s physiology. This research was carried out to study the anatomy of Typhaangustifolia root after 120 days exposure to acid mine drainage at Ex-Mamut copper mine. The roots were become darkened and less of branching. The anatomical study was documented using light microscopy and results showed that the root structure was shrunk and the size of xylem was increased. Most of the cell walls were damaged. The transmission electron microscope (TEM) study was showed that some granules were deposited around root cell walls. The heavy metals affect hormone balance alteration caused the anatomy changes of roots. For ultrastructural study, the result showed that some granules (arrow) were deposited around root cell walls which grown in AMD treatment (Figure 1F). While, no granule was detected in the cells which grown Day 0 and Day 120 without AMD (Figure 1D & 1E). The solubilized metal ions enter the root via either extracellular (apoplastic) or intracellular (symplastic) pathways. It passage into plant cells probably be hampered by the barrier between the vacuole and the outside of the plant cell. Cell wall was the first barrier for metal ions enter the cell, and the ions that cannot entered successful were deposited around the cell walls 50µm E B F D Acknowledgements This research was part of on-going M.S.C project. This research was supported by the Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah. We would also like to thank Innovation and Research Centre of Universiti Malaysia Sabah for the financial support of grant SBK0009. X Introduction Mining activities was the main source of acid mine drainage that can cause long-term impairment to waterways and biodiversity. It occur when the mineral containing sulphide had a series of reactions after exposure to water and oxygen (Skousenet al., 2000). Heavy metals that contribute to high acidity rates of AMD is Iron (Fe), manganese (Mn), zinc (Zn) and aluminum (Al) (Kleinmann, 2006). Environment remediation can be accomplished using aquatic plants such as water hyacinth, and cattail. Plants able to accumulate selected metals mostly in roots and stems, and store other metals in nontoxic form for latter distribution and use (Memonet al., 2001). However, excess concentration can cause toxic to plants and caused the physiology and morphological changes. Typhaangustifoliawas a perennial wetland plant which can grow fast, high biomass accumulation in root. In this study, Typhaangustifoliawas chosen to study the anatomy of its root. It is important to study the anatomy and ultrastructural changes of plant to understand the accumulation and translocation process. Results and Discussion References The anatomy variation of Typhaangustifolia roots which grown 0 day, 120 days treated with AMD and 120 days without AMD were observed using light microscope. The cross-section of root structure that before treatment and grown 120 days without AMD were in normal appearance of epidermis cell and vascular system structure(Figure 1A & 1B). The root cell shapes were distorted and the structure was shrank after 120 days treated with AMD (Figure 1C). The size of xylem was increased compared to the non-AMD root. The maturation rate of plants was affect due to the ability of heavy metals to disrupt the hormone balance of the plants (Gomes et al, 2011). This cause the organization, size xylem and cell shapes of root were changes. Gomes, M. P., Marques, T. C., Nogueira, M. O. G., Gastro, E. M., Soares, Â. M. 2011. Ecophysiological and Anatomical Changes due to Uptake and Accumulation of Heavy Metal in Brachiariadecumbens. Sciences Agriculture. 86(5): 566-573. Kleinmann, R. L. P. 2006. Acid Mine Water Treatment Using Engineered Wetlands. Mine Water and the Environment, 90: 269-275. Memon, A. R., Aktoprakligul, D., Zdemur, A. & Verti, A. 2001. Heavy Metal Accumulation and Detoxification Mechanisms in Plants. Turkish Journal of Botany, 25: 111-121. Skousen, J. G., Sexstone, A. & Ziemkiewicz, P. F. 2000. Acid Mine Drainage Control and Treatment. American Society of Agronomy and American Society for Surface Mining and Reclamation. Agronomy,41: 1-42. Taylor, G. J., Crowder, A.A, Rodden, R., 1984. Formatiand Morphology of an Iron Plaque on the Roots of Typhalatifolia L. grown in Solution Culture. Am, J. Bot, 71: 666-675. Figure 1: Light micrographs in cross-section of Typhaangustifolia root (A-C). A= Day 0; B=Day 120 grown in top soil; C=Day 120 grown in AMD; TEM micrographs of T. angustifolia root (D-F). D=Day 0; E=Day 120 grwon in top soil; F=Day 120 grown in AMD; X= Xylem; PH= Phloem; EP=Epidermis; EX=Exodermis; EN= Endodermis; CW= cell wall; Arrow= heavy metal granule