The contribution of roots and shoots to whole plant nitrate reduction in fast- and slow-growing grass species

被引:47
作者
Scheurwater, I
Koren, M
Lambers, H
Atkin, OK
机构
[1] Univ Utrecht, Dept Plant Ecophysiol, NL-3508 TB Utrecht, Netherlands
[2] Univ Otago, Dept Zool, Dunedin, New Zealand
[3] Univ Western Australia, Fac Agr, Crawley, WA 6009, Australia
[4] Univ York, Dept Biol, York YO1 5YW, N Yorkshire, England
关键词
nitrate uptake; nitrate reductase; nitrogen; nitrogen assimilation; relative growth rate;
D O I
10.1093/jxb/erf008
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
The hypothesis was tested that slow-growing grass species perform a greater proportion of total plant NO3- reduction in their roots than do fast-growing grasses. Eight grass species were selected that differed in maximum relative growth rate (RGR) and net NO3- uptake rate (NNUR). Plants were grown with free access to nutrients in hydroponics under controlled-environment conditions. The site of in vivo NO3- reduction was assessed by combining in vivo NO3- reductase activity (NRA) assays with biomass allocation data, and by analysing the NO3- to amino acid ratio of xylem sap. In vivo NRA of roots and shoots increased significantly with increasing NNUR and RGR. The proportion of total plant NO3- reduction that occurs in roots was found to be independent of RGR and NNUR, with the shoot being the predominant site of NO3- reduction in all species. The theoretical maximum proportion of whole plant nitrogen assimilation that could take place in the roots was calculated using information on root respiration rates, RGR, NNUR, and specific respiratory costs associated with growth, maintenance and ion uptake. The calculated maximum proportion that the roots can contribute to total plant NO3- reduction was 0.37 and 0.23 for the fast-growing Dactylis glomerata L. and the slow-growing Festuca ovina L., respectively. These results indicate that slow-growing grass species perform a similar proportion of total plant NO3- reduction in their roots to that exhibited by fast-growing grasses. Shoots appear to be the predominant site of whole plant NO3- reduction in both fast- and slow-growing grasses when plants are grown with free access to nutrients.
引用
收藏
页码:1635 / 1642
页数:8
相关论文
共 42 条
[1]  
Agrell D, 1997, PLANT PHYSIOL BIOCH, V35, P923
[2]  
ANDREWS M, 1986, PLANT CELL ENVIRON, V9, P511, DOI 10.1111/1365-3040.ep11616228
[3]   THE PARTITIONING OF NITRATE ASSIMILATION BETWEEN ROOT AND SHOOT OF A RANGE OF TEMPERATE CEREALS AND PASTURE GRASSES [J].
ANDREWS, M ;
MORTON, JD ;
LIEFFERING, M ;
BISSET, L .
ANNALS OF BOTANY, 1992, 70 (03) :271-276
[4]  
[Anonymous], ONCOIMMUNOLOGY
[5]   The causes of inherently slow growth in alpine plants: An analysis based on the underlying carbon economies of alpine and lowland Poa species [J].
Atkin, OK ;
Botman, B ;
Lambers, H .
FUNCTIONAL ECOLOGY, 1996, 10 (06) :698-707
[6]   Variation in the components of relative growth rate in ten Acacia species from contrasting environments [J].
Atkin, OK ;
Schortemeyer, M ;
McFarlane, N ;
Evans, JR .
PLANT CELL AND ENVIRONMENT, 1998, 21 (10) :1007-1017
[7]   The relationship between the relative growth rate and nitrogen economy of alpine and lowland Poa species [J].
Atkin, OK ;
Botman, B ;
Lambers, H .
PLANT CELL AND ENVIRONMENT, 1996, 19 (11) :1324-1330
[8]   The response of fast- and slow-growing Acacia species to elevated atmospheric CO2:: an analysis of the underlying components of relative growth rate [J].
Atkin, OK ;
Schortemeyer, M ;
McFarlane, N ;
Evans, JR .
OECOLOGIA, 1999, 120 (04) :544-554
[9]  
BENZIONI A, 1971, PHYSIOL PLANTARUM, V24, P288, DOI 10.1111/j.1399-3054.1971.tb03493.x
[10]   THE PREDICTION OF GEOMETRIC DISTORTIONS IN AIRBORNE SYNTHETIC APERTURE RADAR IMAGERY FROM AUTOFOCUS MEASUREMENTS [J].
BLACKNELL, D ;
FREEMAN, A ;
WHITE, RG ;
WOOD, JW .
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 1987, 25 (06) :775-782