title: Association between minor loading vein architecture and light- and CO2-saturated rates of photosynthetic oxygen evolution among Arabidopsis thaliana ecotypes from different latitudes.
abstract: Through microscopic analysis of veins and assessment of light- and CO2-saturated rates of photosynthetic oxygen evolution, we investigated the relationship between minor loading vein anatomy and photosynthesis of mature leaves in three ecotypes of Arabidopsis thaliana grown under four different combinations of temperature and photon flux density (PFD). All three ecotypes exhibited greater numbers and cross-sectional area of phloem cells as well as higher photosynthesis rates in response to higher PFD and especially lower temperature. The Swedish ecotype exhibited the strongest response to these conditions, the Italian ecotype the weakest response, and the Col-0 ecotype exhibited an intermediate response. Among all three ecotypes, strong linear relationships were found between light- and CO2-saturated rates of photosynthetic oxygen evolution and the number and area of either sieve elements or of companion and phloem parenchyma cells in foliar minor loading veins, with the Swedish ecotype showing the highest number of cells in minor loading veins (and largest minor veins) coupled with unprecedented high rates of photosynthesis. Linear, albeit less significant, relationships were also observed between number and cross-sectional area of tracheids per minor loading vein versus light- and CO2-saturated rates of photosynthetic oxygen evolution. We suggest that sugar distribution infrastructure in the phloem is co-regulated with other features that set the upper limit for photosynthesis. The apparent genetic differences among Arabidopsis ecotypes should allow for future identification of the gene(s) involved in augmenting sugar-loading and -transporting phloem cells and maximal rates of photosynthesis.
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Colorado Boulder, CO, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Cohu
authors.forename: Onno
authors.initials: O
authors.lastname: Muller
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Stewart
authors.forename: Barbara
authors.initials: B
authors.lastname: Demmig-Adams
authors.forename: William W
authors.initials: WW
authors.lastname: Adams
keywords: Arabidopsis thaliana ecotypes; leaf vasculature; light acclimation; phloem; photosynthesis; temperature acclimation; xylem
references.citation: Front Plant Sci. 2013 Jun 14;4:194
references.pmid: 23785375
references.citation: Nature. 2010 Mar 25;464(7288):495-6
references.pmid: 20336123
references.citation: Nat Biotechnol. 2007 May;25(5):593-9
references.pmid: 17435746
references.citation: Tree Physiol. 1999 Apr;19(4_5):235-242
references.pmid: 12651566
references.citation: Photosynth Res. 2012 Sep;113(1-3):181-9
references.pmid: 22791016
references.citation: J Plant Res. 2004 Dec;117(6):481-94
references.pmid: 15583974
references.citation: Plant Physiol. 1997 May;114(1):185-191
references.pmid: 12223698
references.citation: New Phytol. 1990 Nov;116(3):341-381
references.pmid: 33874094
references.citation: Nature. 2004 Apr 22;428(6985):821-7
references.pmid: 15103368
references.citation: BMC Plant Biol. 2011 Aug 31;11:123
references.pmid: 21884586
references.citation: Plant Physiol. 2011 Jan;155(1):64-9
references.pmid: 20971857
references.citation: Ecol Lett. 2010 Feb;13(2):175-83
references.pmid: 19968696
references.citation: Plant Physiol. 2005 May;138(1):451-60
references.pmid: 15863701
references.citation: Am Nat. 2010 Apr;175(4):447-60
references.pmid: 20178410
references.citation: Funct Plant Biol. 2005 Oct;32(10):953-961
references.pmid: 32689191
references.citation: J Exp Bot. 2006;57(2):343-54
references.pmid: 16356943
references.citation: Plant Cell Rep. 2007 Sep;26(9):1635-46
references.pmid: 17458549
references.citation: Funct Plant Biol. 2007 Sep;34(9):822-834
references.pmid: 32689410
references.citation: Plant J. 2012 Apr;70(1):147-56
references.pmid: 22449049
references.citation: New Phytol. 2005 Mar;165(3):839-46
references.pmid: 15720695
references.citation: Proc Biol Sci. 2009 May 22;276(1663):1771-6
references.pmid: 19324775
references.citation: Am J Bot. 2011 Feb;98(2):244-53
references.pmid: 21613113
references.citation: J Exp Bot. 2001 Jul;52(360):1383-400
references.pmid: 11457898
references.citation: Ecol Lett. 2011 Feb;14(2):91-100
references.pmid: 21073643
references.citation: Tree Physiol. 2008 Jan;28(1):123-32
references.pmid: 17938121
references.citation: New Phytol. 2007;173(4):722-731
references.pmid: 17286821
references.citation: Ann Bot. 2002 Jun;89 Spec No:895-905
references.pmid: 12102515
references.citation: Photosynth Res. 1996 Jun;48(3):353-65
references.pmid: 24271476
references.citation: Proc Natl Acad Sci U S A. 2005 Sep 6;102(36):12968-73
references.pmid: 16120679
references.citation: Plant Cell Environ. 2013 Mar;36(3):655-69
references.pmid: 22934921
references.citation: New Phytol. 2012 Jun;194(4):1112-1122
references.pmid: 22432639
references.citation: Plant Sci. 2012 Sep;193-194:70-84
references.pmid: 22794920
references.citation: Plant Physiol. 1978 Mar;61(3):394-7
references.pmid: 16660300
references.citation: Photosynth Res. 2007 Nov-Dec;94(2-3):455-66
references.pmid: 17211580
references.citation: Front Plant Sci. 2013 Jul 05;4:240
references.pmid: 23847643
references.citation: Tree Physiol. 2005 Oct;25(10):1253-63
references.pmid: 16076774
references.citation: Plant Physiol. 2011 May;156(1):90-105
references.pmid: 21441385
references.citation: Proc Natl Acad Sci U S A. 2002 Aug 6;99(16):10876-80
references.pmid: 12149483
references.citation: Annu Rev Plant Biol. 2006;57:361-81
references.pmid: 16669766
references.citation: Nat Biotechnol. 2001 Oct;19(10):965-9
references.pmid: 11581664
references.citation: Tree Physiol. 2007 Mar;27(3):345-52
references.pmid: 17241976
references.citation: Planta. 2000 Jun;211(1):105-11
references.pmid: 10923710