The dynamics of neutral sugars in the rhizosphere of wheat. An approach by13C pulse-labelling and GC/C/IRMS

By Delphine Derrien, C. Marol, J. Balesdent. Plant and Soil, 2004

113 citations recorded by the source corpus.

Rhizodeposition, i.e. the release of carbon into the soil by growing roots, is an important part of the terrestrial carbon cycle. However thein situ nature and dynamics of root-derived carbon in the soil are still poorly understood. Here we made an investigation of the latter in laboratory experiments using13CO2 pulse chase labelling of wheat (Triticum aestivum L.). We analyzed the kinetics of13C-labelled carbon and more specially13C carbohydrates in the rhizosphere. Wheat seedlings-soil mesocosms were exposed to13CO2 for 5 hours in controlled chambers and sampled repeatedly during two weeks for13C/C analysis of organic carbon. After a two-step separation of the soil from the roots, the amount of total organic13C was determined by isotope ratio mass spectrometry as well as the amounts of13C in arabinose, fructose, fucose, glucose, galactose, mannose, rhamnose and xylose. The amount and isotopic ratio of monosaccharides were obtained by capillary gas chromatography coupled with isotope ratio mass spectrometry (GC/C/IRMS) after trimethyl-silyl derivatization. Two fractions were analyzed : total (hydrolysable) and soluble monomeric (water extractable) soil sugars. The amount of organic13C found in the soil, expressed as a percentage of the total photosynthetically fixed13C at the end of the labelling period, reached 16% in the day following labelling and stabilised at 9% after one week. We concluded that glucose under the form of polymers was the dominant moietie of rhizodeposits. Soluble glucose and fructose were also present. But after 2 days, these soluble sugars had disappeared. Forty percent of the root-derived carbon was in the form of neutral sugars, and exhibited a time-increasing signature of microbial sugars. The composition of rhizospheric sugars rapidly tended towards that of bulk soil organic matter.

Subfields: Atmospheric Science, Plant Science, Soil Science

View Paper: https://www.semanticscholar.org/paper/2477336d5854b41f8baabda94bb35a392b7cf81a

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atmospheric Science

1. Y. Kuzyakov

In Plant Science

1. Y. Kuzyakov
2. Davey L. Jones
3. C. Nguyen
4. R. Finlay
5. A. Gunina
6. M. Dippold
7. C. Marol
8. J. Balesdent

In Soil Science

1. Y. Kuzyakov
2. A. Gunina
3. C. Nguyen
4. Davey L. Jones
5. M. Dippold
6. R. Finlay
7. B. Glaser
8. C. Marol

Citations in the corpus

• Turnover of microbial groups and cell components in soil: 13 C analysis of cellular biomarkers (2017, background): “Glucose has a higher concentrations in the soil solution compared to other low molecular weight organics (Fischer et al., 2007), due to its diverse origin: from cellulose decomposition, presence in rhizodeposition (Derrien et al., 2004; Gunina and Kuzyakov, 2015), and synthesis by microorganisms.”
• Sugars in soil and sweets for microorganisms: Review of origin, content, composition and fate (2015, background): “Among the numerous components exuded by roots, carbohydrates are themost abundant (Kraffczyk et al., 1984; Hutsch et al., 2002; Derrien et al., 2004).”
• Carbon flow in the rhizosphere: carbon trading at the soil–root interface (2009, background): “The use of gas chromatography coupled to isotope ratio mass spectrometry allows the dynamic tracking of specific rhizodeposits such as sugars from roots and associated symbionts into soil (Derrien et al. 2004; Paterson et al. 2007).”
• Plant host habitat and root exudates shape soil bacterial community structure (2008, background): “J5 on a eutric cambisol soil cultivated from 1993 to 1997 with winter wheat (Derrien et al., 2004).”