title: LIB spectroscopic and biochemical analysis to characterize lead toxicity alleviative nature of silicon in wheat (Triticum aestivum L.) seedlings.
abstract: The responses of wheat seedling treated with silicon (Si; 10 μM) and lead (Pb; 100 μM) for 7 days have been investigated by analyzing growth, Pb uptake, chlorophyll fluorescence, oxidative stress, antioxidants and nutrients regulation. Results indicated that, Pb significantly (P<0.05) declined growth of seedlings which was accompanied by uptake of Pb. Under Pb stress, fluorescence parameters: Fv/Fm ratio and qP were significantly (P<0.05) decreased while NPQ was increased. Si addition alleviated Pb-induced decrease in growth and alterations in photosynthesis, and also significantly (P<0.05) lowered Pb uptake. Under Pb treatment, oxidative stress markers: hydrogen peroxide and lipid peroxidation were enhanced while DPPH(•) scavenging capacity and total phenolic compounds (TPCs) were decreased significantly, however, Si addition improved the status of antioxidants. The non-protein thiols (NP-SH) showed enhanced level under Pb stress. Pb stress considerably disturbed status of the nutrients as decrease in Ca, P, Mg, Zn and Ni contents while an increase in K, S, B, Cu, Fe, Mn and Na contents were noticed. Si addition maintained status of all the nutrients remarkably. The quickest method of element analysis: LIBS spectra revealed significantly lower uptake of Pb in seedlings grown under Si and Pb combination and same was correlated with the data of AAS. Overall results pointed out that excess Pb uptake disturbed status of nutrients, photosynthetic performance, antioxidant capacity, hence severe oxidative damage to lipids occurred. Further, Si supplementation successfully regulated these parameters by inhibiting Pb uptake hence maintained growth of wheat seedlings. Similar pattern of data recorded by the LIBS, AAS and ICAP-AES confirmed that LIBS may be one of the promising and authentic tools to monitor the mineral and metal distribution in the plants without hampering or disturbing the environment due to its eco-friendly and non-invasive nature.
authors.affiliation: Center of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India. Electronic address: dktripathiau@gmail.com.
authors.forename: Durgesh Kumar
authors.initials: DK
authors.lastname: Tripathi
authors.affiliation: Govt. Ramanuj Pratap Singhdev Post Graduate College, Baikunthpur, Korea-497335, Chhattisgarh, India. Electronic address: vijaypratap.au@gmail.com.
authors.forename: Vijay Pratap
authors.initials: VP
authors.lastname: Singh
authors.affiliation: Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India. Electronic address: sheomohanp@yahoo.co.in.
authors.forename: Sheo Mohan
authors.initials: SM
authors.lastname: Prasad
authors.affiliation: Center of Advanced Study in Botany, Banaras Hindu University, Varanasi 221005, India. Electronic address: nkdubeybhu@gmail.com.
authors.forename: Nawal Kishore
authors.initials: NK
authors.lastname: Dubey
authors.affiliation: D D Pant Interdisciplinary Research Laboratory, Department of Botany, University of Allahabad, Allahabad 211002, India. Electronic address: dkchauhanau@yahoo.com.
authors.forename: Devendra Kumar
authors.initials: DK
authors.lastname: Chauhan
authors.affiliation: Laser Spectroscopy Lab, Department of Physics, University of Allahabad, Allahabad 211002, India. Electronic address: awadheshkrai@rediffmail.com.
authors.forename: Awadesh Kumar
authors.initials: AK
authors.lastname: Rai
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism; D002734:Chlorophyll / Q000737:chemistry / Q000378:metabolism; D007834:Lasers; D007854:Lead / Q000378:metabolism / Q000633:toxicity*; D015227:Lipid Peroxidation / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010636:Phenols / Q000737:chemistry / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D012825:Silicon / Q000378:metabolism / Q000633:toxicity*; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D010636:Phenols; D002734:Chlorophyll; D007854:Lead; D012825:Silicon
keywords: LIBS; Lead toxicity; Nutrient elements; Oxidative stress; Silicon