Improvement of cerium on photosynthesis of maize seedlings under a combination of potassium deficiency and salt stress.

Abstract

Added Ce(3+) can partly substitute for Ca(2+) or Mg(2+) and improve photosynthesis under the deficiency of these elements, but very few studies focused on photosynthetic improvement in maize seedlings caused by K(+) deficiency, salt stress, especially a combination of K(+) deficiency and salt stress. In the present study, the effects of Ce(3+) on the photosynthesis of maize seedlings under the three different stresses were investigated. The results showed that added Ce(3+) under various stresses increased the ratios of free water/bound water and of K(+)/Na(+), the pigment contents, the values of Fv/Fm, Y(II), ETR(II), Y(NPQ), Qp, qL, NPQ, and qN of photosystem II (PSII), the values of Y(I) and ETR(I) of photosystem I (PSI) and the expression levels of LhcII cab1 and rbcL, and decreased the values of Y(NO) and Y(NA). This implied that added Ce(3+) depressed ion toxicity, photodamage of PSII, and acceptor side constraints of PSI, and enhanced adjustable energy dissipation, the responses of photochemistry, and carbon assimilation caused by K(+) deficiency, salt stress, and the combination of K(+) deficiency and salt stress. However, Ce(3+) mitigation of photosynthetic inhibition in maize seedlings caused by the combined stresses was greater than that of salt stress, and Ce(3+) mitigation under salt stress was greater than that under K(+) deficiency. In addition, the results also showed that Ce(3+) cannot improve photosynthesis and growth of maize seedlings under K(+) deficiency by substituting for K(+).

• Authors: Chunxiang Qu, Chao Liu, Fugen Guo, Chenliang Hu, Yuguan Ze, Chunxiao Li, Qiuping Zhou, Fashui Hong
• Journal: Biological trace element research (Biol Trace Elem Res) Vol. 155 Issue 1 Pg. 104-13 (Oct 2013) ISSN: 1559-0720 [Electronic] United States
• PMID: 23892731 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Light-Harvesting Protein Complexes
• Photosystem I Protein Complex
• Photosystem II Protein Complex
• Cerium
• Sodium Chloride
• RbcL protein, plastid
• Ribulose-Bisphosphate Carboxylase
• Potassium

Topics

• Cerium (pharmacology)
• Gene Expression Regulation, Plant (drug effects)
• Light-Harvesting Protein Complexes (genetics)
• Photochemical Processes (drug effects)
• Photosynthesis (drug effects)
• Photosystem I Protein Complex (metabolism)
• Photosystem II Protein Complex (metabolism)
• Potassium (metabolism)
• Reverse Transcriptase Polymerase Chain Reaction
• Ribulose-Bisphosphate Carboxylase (genetics)
• Seedlings (drug effects, genetics, metabolism)
• Sodium Chloride (metabolism)
• Stress, Physiological
• Zea mays (drug effects, genetics, metabolism)