Journal
PHOTOSYNTHETICA
Volume 46, Issue 3, Pages 400-409Publisher
SPRINGER
DOI: 10.1007/s11099-008-0072-2
Keywords
ATPase; chlorophyll fluorescence induction; fatty acids; net photosynthetic rate; peptides; Nicotiana; violaxanthin de-epoxidase; xanthophyll cycle
Categories
Funding
- National Natural Science Foundation of China [30671259]
- Tobacco Supervising Organization of Shandong province in China [KN77]
Ask authors/readers for more resources
Glycine betaine (GB) is an effective compatible solute that improves the tolerance in plants to various stresses. We investigated the effects of 2 mM GB applied to the roots of a tobacco (Nicotiana tabacum L.) cultivar on enhancing photosynthesis under low-temperature (LT) stress (5/5 degrees C, 12/12 h, 300 mu mol m(-2) s(-1)) and in the subsequent recovery (25/18 degrees C) from the stress. The net photosynthetic rate, intrinsic efficiency measured as the ratio of variable to maximum fluorescence, and actual efficiency of the photochemistry of photosystem 2 as well as the ATPase activity in the thylakoid membrane decreased, and a distinct K step in the fluorescence transient O-J-I-P appeared under cold stress. Exogenous GB alleviated the decrease in all these parameters. The LT-stress induced the accumulation of 33-66 kDa polypeptides and decreased the proportion of unsaturated fatty acids in the thylakoid membrane. In plants subjected to LT-stress, GB protected these polypeptides from damage and enhanced the proportion of unsaturated fatty acids. An increase in non-radiative energy dissipation (NPQ) may be involved in the improvement of the function of the thylakoid membrane by GB since exogenous GB protected violaxanthin de-epoxidase and enhanced NPQ.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available