Please use this identifier to cite or link to this item:
Title: Photosynthetic acclimation to elevated CO2 in relation to Rubisco gene expression in three C3 species
Authors: Pandurangam, Vijai
Sharma-Natu, Poonam
Sreekanth, B
Ghildiyal, M C
Keywords: CO2 enrichment;Photosynthesis;rbcs;Rubisco;Saccharide
Issue Date: May-2006
Publisher: CSIR
Abstract: Wheat (Triticum aestivum L. var. DL 1266-5), sunflower (Helianthus annuus L. var. MSFH 17) and mungbean [Vigna radiata (L.) Wilczek var. P 9072] were grown in field under atmospheric (360±10 cm3 m-3, AC) and elevated (650±50 cm3 m-3, EC) CO2 concentrations in open top chambers for entire period of growth and development. Photosynthetic acclimation to elevated CO2 was examined by comparing photosynthesis rate (Pn), Pn/Ci curves, leaf contents of RuBP carboxylase/oxygenase (Rubisco), change in the transcripts of Rubisco small subunit (SSU) gene and leaf carbohydrate constituents in AC and EC grown plants. The study indicated that photosynthetic acclimation to elevated CO2 concentration in wheat occurred because of down regulation of Rubisco, through limitation imposed on Rubisco SSU gene expression, as a consequence of sugar accumulation in the leaves. Leaf starch accumulators, sunflower and mungbean, showed no down regulation of Pn under EC. The Rubisco contents (%) in leaf soluble protein and rbcS transcript levels were not significantly affected in EC plants compared to AC plants of sunflower and mungbean. The study indicated that accumulation of excess assimilates in the leaves as starch was less inhibitory to Pn and would, therefore, be an important trait for sustenance of Pn not only under EC, but also under AC, where Pn inhibited by end products.
Page(s): 408-415
ISSN: 0975-1009 (Online); 0019-5189 (Print)
Appears in Collections:IJEB Vol.44(05) [May 2006]

Files in This Item:
File Description SizeFormat 
IJEB 44(5) 408-415.pdf255.01 kBAdobe PDFView/Open

Items in NOPR are protected by copyright, with all rights reserved, unless otherwise indicated.