TY - JOUR
T1 - The influence of silicon on barley growth, photosynthesis and ultra-structure under chromium stress
AU - Ali, Shafaqat
AU - Farooq, Muhammad Ahsan
AU - Yasmeen, Tahira
AU - Hussain, Sabir
AU - Arif, Muhammad Saleem
AU - Abbas, Farhat
AU - Bharwana, Saima Aslam
AU - Zhang, Guoping
N1 - Funding Information:
The project was supported by Zhejiang Bureau of Science and Technology ( 2009C12050 ).
PY - 2013/3/1
Y1 - 2013/3/1
N2 - Silicon (Si) is generally considered as a benefic element for higher plants, especially for those grown under abiotic stressed environments. Current study is carried out in a hydroponic experiment to analyze the effect of Si application on barley growth, photosynthesis and ultra-structure under chromium (Cr) stress. The treatments consisted of three Si (0, 1 and 2mM) and two Cr (0 and 100μM) levels. The results showed that Si application at both levels enhanced plant growth relative to the control, and alleviated Cr toxicity, reflected by significant increase in growth and photosynthetic parameters, such as SPAD value, net photosynthetic rate (Pn), cellular CO2 concentration (Ci), stomatal conductance (Gs) and transpiration rate (Tr), and chlorophyll fluorescence efficiency (Fv/Fm), with 2mM Si having greater effect than 1mM Si. Cr stress caused ultra-structural disorders in leaves, such as uneven swelling of chloroplast, increased amount of plastoglobuli, disintegrated and disappeared thylakoid membranes, increased size and number of starch granules in leaves, and root ultra-structural modification, including increased vacuolar size, presence of Cr metal in cell walls and vacuoles, disruption and disappearance of nucleus. Exogenous Si alleviated these ultra-structural disorders both in roots and leaves. Apparently, Si and Cr behaved antagonistically, indicating that Si could be a candidate for Cr detoxification in crops under Cr-contaminated soil.
AB - Silicon (Si) is generally considered as a benefic element for higher plants, especially for those grown under abiotic stressed environments. Current study is carried out in a hydroponic experiment to analyze the effect of Si application on barley growth, photosynthesis and ultra-structure under chromium (Cr) stress. The treatments consisted of three Si (0, 1 and 2mM) and two Cr (0 and 100μM) levels. The results showed that Si application at both levels enhanced plant growth relative to the control, and alleviated Cr toxicity, reflected by significant increase in growth and photosynthetic parameters, such as SPAD value, net photosynthetic rate (Pn), cellular CO2 concentration (Ci), stomatal conductance (Gs) and transpiration rate (Tr), and chlorophyll fluorescence efficiency (Fv/Fm), with 2mM Si having greater effect than 1mM Si. Cr stress caused ultra-structural disorders in leaves, such as uneven swelling of chloroplast, increased amount of plastoglobuli, disintegrated and disappeared thylakoid membranes, increased size and number of starch granules in leaves, and root ultra-structural modification, including increased vacuolar size, presence of Cr metal in cell walls and vacuoles, disruption and disappearance of nucleus. Exogenous Si alleviated these ultra-structural disorders both in roots and leaves. Apparently, Si and Cr behaved antagonistically, indicating that Si could be a candidate for Cr detoxification in crops under Cr-contaminated soil.
KW - Alleviation
KW - Barley
KW - Chromium
KW - Silicon
KW - Toxicity
UR - http://www.scopus.com/inward/record.url?scp=84873134248&partnerID=8YFLogxK
U2 - 10.1016/j.ecoenv.2012.11.015
DO - 10.1016/j.ecoenv.2012.11.015
M3 - Article
C2 - 23260243
AN - SCOPUS:84873134248
SN - 0147-6513
VL - 89
SP - 66
EP - 72
JO - Ecotoxicology and Environmental Safety
JF - Ecotoxicology and Environmental Safety
ER -
