Synergistic action of ultraviolet-B radiation and cadmium on the growth of wheat seedlings.
The increase in ground level UV-B radiation as a result of stratospheric ozone depletion may have major deleterious effects on crop photosynthesis and productivity. Plants are exposed to UV-B and other xenobiotics simultaneously in today's industrialized world. The present studies were undertaken to see the effect of dual stress of UV-B and Cd2+ exposure on the growth of wheat (Triticum aestivum L.) seedlings. The plants grown in 0.25, 0.5, 1.0, 2.5, and 5.0 ppm Cd2+-supplemented medium were exposed to UV-B for 30 min (2 J, 0.4 mW/cm(2)) per day. After 5 and 10 days of treatment the combined stress of UV-B and Cd2+ resulted in reduction of biomass yield, growth, and chlorophyll content and changes in protein, free amino acid, starch, and total reducing sugar content. These data support the assumption that UV-B may have a regulatory role besides damaging effects and that an increased UV-B environment will likely increase this regulatory influence of UV-B radiation. The results also indicate that the adverse effects of one stress may be modulated in the presence of other stresses.
Shukla
Umesh C
UC
Industrial Toxicology Research Center, Lucknow 226 001, India.
Joshi
Prakash C
PC
Kakkar
Poonam
P
D000596:Amino Acids / Q000032:analysis; D002104:Cadmium / Q000633:toxicity*; D002734:Chlorophyll / Q000032:analysis; D004780:Environment, Controlled; D004785:Environmental Pollutants / Q000633:toxicity*; D010940:Plant Proteins / Q000096:biosynthesis; D018514:Plant Structures; D013213:Starch / Q000096:biosynthesis; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development* / Q000528:radiation effects*; D014466:Ultraviolet Rays
D000596:Amino Acids; D004785:Environmental Pollutants; D010940:Plant Proteins; D002104:Cadmium; D002734:Chlorophyll; D013213:Starch