Ultraviolet-A induced changes in photosystem II of thylakoids: effects of senescence and high growth temperature.
Ultraviolet-A (UV-A) radiation induced changes in photosystem II (PS II) of senescing leaves of wheat seedlings were investigated. UV-A radiation did not show any significant effect on the level of photosynthetic pigments. However, the decline in F(v)/F(m) and oxygen evolution rate indicated the damaging effect of the radiation on primary photochemistry of PS II. Modification at the Q(B)-binding site was inferred from the observed downshift of peak temperature of thermoluminescence (TL) B-bands. The UV-A induced changes in PS II of chloroplasts from senescing leaves were found to be synergistically accelerated by high growth temperature.
Nayak
L
L
School of Life Sciences, Sambalpur University, Jyoti Vihar, Sambalpur, India.
Biswal
B
B
Ramaswamy
N K
NK
Iyer
R K
RK
Nair
J S
JS
Biswal
U C
UC
D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000528:radiation effects*; D013696:Temperature; D020524:Thylakoids / Q000737:chemistry / Q000528:radiation effects*; D014908:Triticum / Q000254:growth & development / Q000528:radiation effects*; D014466:Ultraviolet Rays
D045332:Photosystem II Protein Complex