Uptake arsenic by plants: Effects on mineral nutrition, growth and antioxidant capacity

Abstract

Arsenic (As) is the one of the main environmental pollutant and phytoremediation is an effective tool for its removal of the environment. In this study, Pistia stratiotes were exposed to seven As concentrations (0, 3, 7, 10, 13, 16 and 20 µM) and then, the influence of this metalloid on growth, mineral nutrition and photosynthesis were analyzed. It was observed that this species have a high affinity for As and pollutant uptake occurs rapidly. The uptake of Cu, Mn, Fe and P increased until the concentration of 13 µM, decreasing in higher concentrations.The Mg content also decreased from this same concentration. No effects were observed in the uptake of K, Ca and Zn. Growth rate and photosynthetic pigments content were negatively affected by As. Despite this decrease, the growth was maintained up to the concentration of 13 µM of As. The maintenance of growth and the change in nutrients uptake are probably related with the increase in antioxidant capacity of the plant, indicating resistance to the pollutant. In this way, P. stratiotes is probably an efficient phytoremediator of As, even when in concentrations up to one hundred times greater than those permitted in water for human consumption. Key words: Aquatic plant species; environmental pollution; phytoremediation. RESUMEN El Arsénico (As) es uno de los principales contaminantes ambientales y la fitorremediación se presenta como una herramienta efectiva para retirar este elemento del medio ambiente. En el presente estudio se analizó la influencia de este elemento en el crecimiento, nutrición mineral y fotosíntesis dePistia stratiotes bajo siete concentraciones de As (0, 3, 7, 10, 13, 16 y 20 µM

Phytoremediation Potential, Photosynthetic and Antioxidant Response to Arsenic-Induced Stress of Dactylis glomerata L. Sown on Fly Ash Deposits

“…In the leaves of D. glomerata sown on fly ash deposits, the amount of anthocyanins was lower than at the control site (71%) and it significantly decreased with high As content (r = −0.77). Unlike our results, As enhanced production of anthocyanins in Azzola caroliliana [142], Lemna gibba [134] and Festuca rubra grown on fly ash deposits [13]. According to [143], the redox status of the plastoquinone (PQ) pool regulates anthocyanin biosynthesis genes.…”

“…Our results show that reduced content of Chl a, Chl b, Chl a+b, the ratio of Chl a/b, and total carotenoids in the leaves of D. glomerata sown on fly ash deposits in relation to the control site (66%, 53%, 63%, 82%, and 75%, respectively) can be the result of toxic As concentrations in leaves (r = −0.88, r = −0.85, r = −0.87, r = −0.95, and r = −0.84, respectively) indicating high sensitivity of photopigments to As stress. As decreased chlorophylls and carotenoids content in Zea mays [37], Avena sativa [39], Oryza sativa [132], Sesuvium portulacastrum [133], Hydrilla verticillata [130], Pistia stratoides [134], Lemna gibba [135], Festuca rubra [13], Nostoc muscorum [131], whereas [136] Lactuca sativa did not show any changes in the concentrations of photopigments under As stress. Generally, Chl a builds the light harvesting pigment complex (LHCP complex) and the core of photochemical reaction centers (PSI-P700 and PSII-P680) whereas Chl b is the accessory pigment which can absorb light and transfer energy to the other pigment molecules [137,138].…”

Thidiazuron induced efficientin vitromultiplication andex vitroconservation ofRauvolfia serpentina– a potent antihypertensive drug producing plant

“…The carotenoid plays an important role in the protection of the chlorophyll pigments under stress conditions that might be generated during acclimatization. [74] The carotenoid content was increased during subsequent acclimatization periods. Net photosynthetic rate (P N ) decreased to 1.5 § 0.27 mmol CO 2 m ¡2 s ¡1 after seven days of transplantation against 1.8 § 0.23 mmol CO 2 m ¡2 s ¡1 in 0 day plantlets.…”

Root application of selenite can simultaneously reduce arsenic and cadmium accumulation and maintain grain yields, but show negative effects on the grain quality of paddy rice

“…Long-term Cd intake can cause functional changes in the urinary system and affect bone development, and long-term As intake may cause various cancers such as those of the bladder, lungs, and liver (Farnese et al, 2014;Kobayashi et al, 2002).…”