TY  - JOUR
AB  - Soil contamination with heavy metals has become a worldwide problem, leading to losses in agricultural yield and hazardous health effects as they enter the food chain . Nickel as an essential trace element, affect a number of biochemical and physiological processes in plants in toxic levels.  The most common symptoms are chlorosis, and inhibited photosynthesis and respiration.  Zea mays seeds were germinated and cultured on nutrient solution with nickel concentrations of 50-200 μmol for a period of two weeks.  Studied physiological makers included photosynthetic pigments content, the rate of Hill reaction, K+ efflux and carbohydrate leakage  from the roots to the external solution and cell death as a Ni-induced membrane damage. By increasing Ni concentration up to 100  μmol, the content of chlorophyll a increased, but decreased at 200 μmol Ni. No significant changes in chlorophyll b and carotinoids content observed.The rate of Hill reaction as an ability of chlorophyll a in the reaction center of PSII680 to split water, decreased by increasing Ni concentration. Different concentrations of nickel increased the K+ efflux and sugar leakage from roots to the culture and the cell death of root tips. The present results suggested that the disruption of photosynthesis by Ni cannot be attributed to any single factor and appears to result from its combined effects on chloroplast structure, chlorophyll content and photosynthetic protein complexes and treatment with different levels of nickel may  induce structural damage and alterations in membrane properties by generation of reactive oxygen species.
AU  - Ghasemi, F.
AU  - Heidari, R.
AU  - Jameii, R.
AU  - Purakbar, L.
DA  - 2012
KW  - chlorophyll content;
Hill reaction;
K+ efflux;
nickel toxicity;
Zea mays
M1  - 4
M3  - ORIGINAL ARTICLE
PY  - 2012
SE  - 55
SN  - 1997-0838
SP  - 55-61
ST  - Effects of Ni2+ toxicity on Hill reaction and membrane functionality in maize
T2  - Journal of Stress Physiology & Biochemistry
TI  - Effects of Ni2+ toxicity on Hill reaction and membrane functionality in maize
UR  - http://www.jspb.ru/issues/2012/N4/JSPB_2012_4_55-61.pdf
VL  - 8
ID  - 9
ER  -