The Nitrogen Use Efficiency of C3 and C4 Plants III. Leaf Nitrogen Effects on the Activity of Carboxylating Enzymes in Chenopodium album (L.) and Amaranthus retroflexus (L.)

Department of Botany, University of California, Davis, California 95616.
Plant physiology (Impact Factor: 6.84). 11/1987; 85(2):355-9. DOI: 10.1104/pp.85.2.355
Source: PubMed


The relationships between leaf nitrogen content per unit area (N(a)) and (a) the initial slope of the photosynthetic CO(2) response curve, (b) activity and amount of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC), and (c) chlorophyll content were studied in the ecologically similar weeds Chenopodium album (C(3)) and Amaranthus retroflexus (C(4)). In both species, all parameters were linearly dependent upon leaf N(a). The dependence of the initial slope of the CO(2) response of photosynthesis on N(a) was four times greater in A. retroflexus than in C. album. At equivalent leaf N(a) contents, C. album had 1.5 to 2.6 times more CO(2) saturated Rubisco activity than A. retroflexus. At equal assimilation capacities, C. album had four times the Rubisco activity as A. retroflexus. In A. retroflexus, a one to one ratio between Rubisco activity and photosynthesis was observed, whereas in C. album, the CO(2) saturated Rubisco activity was three to four times the corresponding photosynthetic rate. The ratio of PEPC to Rubisco activity in A. retroflexus ranged from four at low N(a) to seven at high N(a). The fraction of organic N invested in carboxylation enzymes increased with increased N(a) in both species. The fraction of N invested in Rubisco ranged from 10 to 27% in C. album. In A. retroflexus, the fraction of N(a) invested in Rubisco ranged from 5 to 9% and the fraction invested in PEPC ranged from 2 to 5%.

Download full-text


Available from: Robert W Pearcy
  • Source
    • "The SPAD measure is mainly influenced by absorbancetransmittance red light of 650 nm by the leaf chl conc (Markwell et al., 1995). In addition, Rubisco alone shares 30%, but Rubisco, PEPC and pyruvate orthophosphate dikinase shares 50% of the total soluble proteins in leaves of C4 plant species (Sugiyama et al., 1984; Sage et al., 1987; Makino et al., 2003). But, most of the hybrids have parallel dynamics of N and chl concentration in the leaves except in long-stay-green genotypes (Thomas et al., 2002; Ho¨rtensteiner and Feller, 2002; Ho¨rtensteiner, 2006). "
    [Show description] [Hide description]
    DESCRIPTION: Maize leaf chlorophyll dynamics
    Full-text · Research · Dec 2015
  • Source
    • "Photosynthetic proteins encompass the majority of leaf nitrogen—for example, Rubisco (EC typically accounts for between 10% and 30% of leaf nitrogen content but can account for up to 50% of leaf nitrogen content (Ellis, 1979; Sage et al., 1987; Evans, 1989). Through Rubisco, carbon source activity is directly connected with leaf nitrogen sink activity, providing one way in which source and sink activity are intrinsically coordinated. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Growth is a major component of fitness in all organisms, an important mediator of competitive interactions in plant communities, and a central determinant of yield in crops. Understanding what limits plant growth is therefore of fundamental importance to plant evolution, ecology, and crop science, but each discipline views the process from a different perspective. This review highlights the importance of source–sink interactions as determinants of growth. The evidence for source- and sink-limitation of growth, and the ways in which regulatory molecular feedback systems act to maintain an appropriate source:sink balance, are first discussed. Evidence clearly shows that future increases in crop productivity depend crucially on a quantitative understanding of the extent to which sources or sinks limit growth, and how this changes during development. To identify bottlenecks limiting growth and yield, a holistic view of growth is required at the whole-plant scale, incorporating mechanistic interactions between physiology, resource allocation, and plant development. Such a holistic perspective on source–sink interactions will allow the development of a more integrated, whole-system level understanding of growth, with benefits across multiple disciplines.
    Full-text · Article · Oct 2015 · Journal of Experimental Botany
  • Source
    • "hesis capacity is also more profound in C 3 species than in C 4 species ( Morgan et al . , 2001 ; Duarte et al . , 2014 ) , due in part to the N dilution , possibly because C 3 plants need to invest more N from the leaf into Rubisco , relative to the C 4 species , so that the former may easily undergo more severe N dilution under CO 2 enrichment ( Sage et al . , 1987 ; Yin , 2002 ; Luo et al . , 2004 ; Sage , 2004 ) , with no CCM ( von Caemmerer and Furbank , 2003 ) ."
    [Show abstract] [Hide abstract]
    ABSTRACT: It is well known that plant photosynthesis and respiration are two fundamental and crucial physiological processes, while the critical role of the antioxidant system in response to abiotic factors is still a focus point for investigating physiological stress. Although one key metabolic process and its response to climatic change have already been reported and reviewed, an integrative review, including several biological processes at multiple scales, has not been well reported. The current review will present a synthesis focusing on the underlying mechanisms in the responses to elevated CO2 at multiple scales, including molecular, cellular, biochemical, physiological, and individual aspects, particularly, for these biological processes under elevated CO2 with other key abiotic stresses, such as heat, drought, and ozone pollution, as well as nitrogen limitation. The present comprehensive review may add timely and substantial information about the topic in recent studies, while it presents what has been well established in previous reviews. First, an outline of the critical biological processes, and an overview of their roles in environmental regulation, is presented. Second, the research advances with regard to the individual subtopics are reviewed, including the response and adaptation of the photosynthetic capacity, respiration, and antioxidant system to CO2 enrichment alone, and its combination with other climatic change factors. Finally, the potential applications for plant responses at various levels to climate change are discussed. The above issue is currently of crucial concern worldwide, and this review may help in a better understanding of how plants deal with elevated CO2 using other mainstream abiotic factors, including molecular, cellular, biochemical, physiological, and whole individual processes, and the better management of the ecological environment, climate change, and sustainable development.
    Full-text · Article · Oct 2015 · Frontiers in Plant Science
Show more