PMID- 19902302
OWN - NLM
STAT- MEDLINE
DCOM- 20100315
LR  - 20211020
IS  - 1573-1561 (Electronic)
IS  - 0098-0331 (Linking)
VI  - 35
IP  - 11
DP  - 2009 Nov
TI  - In situ silicone tube microextraction: a new method for undisturbed sampling of 
      root-exuded thiophenes from marigold (Tagetes erecta L.) in soil.
PG  - 1279-87
LID - 10.1007/s10886-009-9711-8 [doi]
AB  - The difficulties of monitoring allelochemical concentrations in soil and their 
      dynamics over time have been a major barrier to testing hypotheses of 
      allelopathic effects. Here, we evaluate three diffusive sampling strategies that 
      employ polydimethylsiloxane (PDMS) sorbents to map the spatial distribution and 
      temporal dynamics of root-exuded thiophenes from the African marigold, Tagetes 
      erecta. Solid phase root zone extraction (SPRE) probes constructed by inserting 
      stainless steel wire into PDMS tubing were used to monitor thiophene 
      concentrations at various depths beneath marigolds growing in PVC pipes. PDMS 
      sheets were used to map the distribution of thiophenes beneath marigolds grown in 
      thin glass boxes. Concentrations of the two major marigold thiophenes measured by 
      these two methods were extremely variable in both space and time. Dissection and 
      analysis of roots indicated that distribution of thiophenes in marigold roots 
      also was quite variable. A third approach used 1 m lengths of PDMS microtubing 
      placed in marigold soil for repeated sampling of soil without disturbance of the 
      roots. The two ends of the tubing remained out of the soil so that solvent could 
      be washed through the tubing to collect samples for HPLC analysis. Unlike the 
      other two methods, initial experiments with this approach show more uniformity of 
      response, and suggest that soil concentrations of marigold thiophenes are 
      affected greatly even by minimal disturbance of the soil. Silicone tube 
      microextraction gave a linear response for alpha-terthienyl when maintained in 
      soils spiked with 0-10 ppm of this thiophene. This method, which is 
      experimentally simple and uses inexpensive materials, should be broadly 
      applicable to the measurement of non-polar root exudates, and thus provides a 
      means to test hypotheses about the role of root exudates in plant-plant and other 
      interactions.
FAU - Mohney, Brian K
AU  - Mohney BK
AD  - Department of Chemistry, Ashland University, Ashland, OH 44805, USA.
FAU - Matz, Tricia
AU  - Matz T
FAU - Lamoreaux, Jessica
AU  - Lamoreaux J
FAU - Wilcox, David S
AU  - Wilcox DS
FAU - Gimsing, Anne Louise
AU  - Gimsing AL
FAU - Mayer, Philipp
AU  - Mayer P
FAU - Weidenhamer, Jeffrey D
AU  - Weidenhamer JD
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20091110
PL  - United States
TA  - J Chem Ecol
JT  - Journal of chemical ecology
JID - 7505563
RN  - 0 (Dimethylpolysiloxanes)
RN  - 0 (Pheromones)
RN  - 0 (Silicones)
RN  - 0 (Soil)
RN  - 0 (Thiophenes)
RN  - 63148-62-9 (baysilon)
RN  - 9002-86-2 (Polyvinyl Chloride)
RN  - Y4S76JWI15 (Methanol)
SB  - IM
MH  - Diffusion
MH  - Dimethylpolysiloxanes/chemistry
MH  - Glass/chemistry
MH  - Hydrophobic and Hydrophilic Interactions
MH  - Methanol/chemistry
MH  - Pheromones/analysis/chemistry/isolation & purification/metabolism
MH  - Plant Roots/*chemistry/metabolism
MH  - Polyvinyl Chloride/chemistry
MH  - Silicones/*chemistry
MH  - *Soil
MH  - Solid Phase Microextraction/*methods
MH  - Tagetes/*chemistry/metabolism
MH  - Thiophenes/*analysis/chemistry/*isolation & purification/metabolism
MH  - Time Factors
EDAT- 2009/11/11 06:00
MHDA- 2010/03/17 06:00
CRDT- 2009/11/11 06:00
PHST- 2009/08/20 00:00 [received]
PHST- 2009/10/20 00:00 [accepted]
PHST- 2009/10/06 00:00 [revised]
PHST- 2009/11/11 06:00 [entrez]
PHST- 2009/11/11 06:00 [pubmed]
PHST- 2010/03/17 06:00 [medline]
AID - 10.1007/s10886-009-9711-8 [doi]
PST - ppublish
SO  - J Chem Ecol. 2009 Nov;35(11):1279-87. doi: 10.1007/s10886-009-9711-8. Epub 2009 
      Nov 10.