Nitrogen isotope composition of tomato (Lycopersicon esculentumMill. cv. T‐5) grown under ammonium or nitrate nutrition

Plant, Cell and Environment - Tập 19 Số 11 - Trang 1317-1323 - 1996
R. Evans1, Arnold J. Bloom2, Scott S. Sukrapanna2, James R. Ehleringer3
1Biological Sciences, University of Arkansas, Fayetteville, AR 72701
2Department of Vegetable Crops , University of California , Davis , CA , 95616
3Stable Isotope Ratio Facility for Environmental Research, Dept of Biology, University of Utah, Salt Lake City, UT 84112, USA

Tóm tắt

ABSTRACTStudies that quantify plant δ15N often assume that fractionation during nitrogen uptake and intra‐plant variation in δ15N are minimal. We tested both assumptions by growing tomato (Lycopersicon esculetumMill. cv. T‐5) at NH4+or NO3concentrations typical of those found in the soil. Fractionation did not occur with uptake; whole‐plant δ15N was not significantly different from source δ15N for plants grown on either nitrogen form. No intra‐plant variation in δ15N was observed for plants grown with NH+4. In contrast. δ15N of leaves was as much as 5.8% greater than that of roots for plants grown with NO3. The contrasting patterns of intra‐plant variation are probably caused by different assimilation patterns. NH+4is assimilated immediately in the root, so organic nitrogen in the shoot and root is the product of a single assimilation event. NO3assimilation can occur in shoots and roots. Fractionation during assimilation caused the δ15N of NO3to become enriched relative to organic nitrogen; the δ15N of NO3was 11.1 and 12.9% greater than the δ15N of organic nitrogen in leaves and roots, respectively. Leaf δ15N may therefore be greater than that of roots because the NO3available for assimilation in leaves originates from a NO3pool that was previously exposed to nitrate assimilation in the root.

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Tài liệu tham khảo

Andrews M., 1986, The partitioning of nitrate assimilation between root and shoot of higher plants, Plant, Cell and Environment, 9, 511, 10.1111/1365-3040.ep11616228

10.1071/PP9880407

Bloom A.J., 1988, Ammonium and nitrate as nitrogen sources for plant growth, ISI Atlas of Science, 1, 55

10.1007/978-94-009-2237-2_8

Ehleringer J.R., 1988, Stable Isotopes in Ecological Research, 1

10.1007/BF00627735

10.1016/S0003-2670(01)84751-6

Glass A.D.M., 1988, Nitrogen uptake by plant roots, ISI Atlas of Science, 1, 151

10.1111/j.1365-3040.1992.tb01650.x

10.1016/B978-0-12-334910-1.50005-4

10.4319/lo.1992.37.7.1447

10.1007/978-3-662-09998-8

10.1007/978-94-010-9117-6

10.1104/pp.99.4.1582

10.1104/pp.66.1.51

10.1104/pp.105.1.435

Larsson C.M., 1992, Nitrogen Metabolism of Plants, 71, 10.1093/oso/9780198577522.003.0006

Lea P.J., 1992, Nitrogen Metabolism of Plants, 153, 10.1093/oso/9780198577522.003.0011

Mariotti A., 1980, Fractionnements isotopiques de I'azote lors des processus d'absorption des nitrates et de fixation de I'azote atmospherique par les plantes, Physiologie Vegetale, 18, 163

10.1104/pp.69.4.880

10.1021/ac00275a023

10.1093/jxb/40.2.207

Neter J., 1985, Applied Linear Statistical Models

Nye P.H., 1977, Solute Movement in the Soil–Root System

10.1111/j.1365-3040.1992.tb01660.x

10.1093/jxb/37.11.1619

10.1111/j.1469-8137.1992.tb01088.x

10.1104/pp.82.3.675

Shearer G., 1986, N2‐fixation in field settings: Estimations based on natural 15N abundance, Australia Journal of Plant Physiology, 13, 699

10.1007/BF00379714

10.1093/jxb/42.11.1455

10.1111/j.1365-3040.1993.tb00868.x

10.1104/pp.86.3.778

10.1016/0003-2697(80)90325-5

Ullrich W.R., 1992, Nitrogen Metabolism of Plants, 121, 10.1093/oso/9780198577522.003.0009

10.1111/j.1399-3054.1984.tb06342.x

10.1016/0003-2697(79)90336-1

Wang M.Y., 1993, Ammonium uptake by rice roots. I. Fluxes and subcellular distribution of 13NH+ 4, Plant Physiology, 103, 1249, 10.1104/pp.103.4.1249

10.1104/pp.103.4.1259

10.1104/pp.104.3.899

Yoneyama T., 1989, Variations in the natural abundance of 15N in nitrogenous fractions of komatsuna plants supplied with nitrate, Plant and Cell Physiology, 30, 957

Yoneyama T., 1991, Fractionation of nitrogen isotopes during the uptake and assimilation of ammonia by plants, Plant and Cell Physiology, 32, 1211