Effect of Different Nitrogen Levels on the Photosynthesis and Growth of Sweet Sorghum Seedlings under Salt Stress

Abstract:

Seedlings of sweet sorghum were supplied with 0.1 mmol L^-1, 2 mmol L^-1, 5 mmol L^-1 and 10 mmol L^-1 nitrogen fertilizers under 0% or 0.6% NaCl conditions. Then the growth parameters of the seedlings including photosynthetic gas exchange and leaf chlorophyll a fluorescence were determined. Results showed that the seedlings grew worse under 0.6% NaCl. Furthermore, with the increase of nitrogen level, the net photosynthetic rate (Pn), transpiration rate (Tr), the maximum photochemical efficiency of PSII (PHI(Po)) , the driving force on light absorption basis (D.F), the active reaction centers per cross section (RS/CSm), trapped energy per cross section (TRo/CSm) and PQ size of photosystem (PS) II (Sm) all increased and reached the peak at 5 mmol L^-1 nitrogen level. On the other hand, heat dispassion per cross section (DIo/CSm) and the close extent of PS II reaction center (Vj and M₀) all decreased with nitrogen level. The results indicated that the optimum nitrogen level for sweet sorghum is about 5 mmol L^-1.

• Periodical: Advanced Materials Research (Volumes 726-731)
• Pages: 4352-4357
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.726-731.4352
• Online since: August 2013
• Authors: Hai Fan, Guo Hua Meng, Ran Ran Cheng, Ling Li, Xu Yun, Bao Shan Wang
• Keywords: Chlorophyll Fluorescence, Nitrogen Level, Photosynthesis, Salt Stress, Sweet Sorghum [Sorghum Bicolor (L.) Moench]

References

[1] BVS Reddy, S Ramesh, Reddy P Sanjana, B Ramaih et.al. Sweet sorghum - A potential alternative raw material for bio-ethanol and bio-energy. International Sorghum and Millets Newsletter 46:79-86. (2005)

[2] J Yang. The development and prospect of the research of salinized soil in China. Acta Pedologica Sinica. 45(5):837-845. (2008) in Chinese

[3] Peter J. Lea, Jeans-F. Morot-Gaudry. Plant Nitrogen. Springer-Verlag. Berlin. (2001)

[4] S Rachmilevitch, B Huang, H Lambers. Assimilation and allocation of carbon and nitrogen of thermal and nonthermal Agrostis species in response to high soil temperature. 170(3):479-490. (2006)

DOI: 10.1111/j.1469-8137.2006.01684.x

[5] RJ Strasser, M Tsimilli-Michael and A Srivastava. Chlorophyll a Fluorescence. Advances in Photosynthesis and Respiration. In GC Papageorgiou and Govindjee (eds), Chlorophyll a Fluorescence: A Signature of Photosynthesis. Springer, pp.321-362. (2004)

DOI: 10.1007/978-1-4020-3218-9_12

[6] OK. Atkin, AH. Millar, P. Gardeström et. al. Photosynthesis, Carbohydrate Metabolism and Respiration in Leaves of Higher Plants. In RC. Leegood, TD. Sharkey and S.Caemmerer (eds), Photosynthesis: Physiology and Metabolism. Kluwer Academic Publishers, pp.153-175. (2004)

DOI: 10.1007/0-306-48137-5_7