Evaluation of Three Electronic Noses for Detecting Incipient Wood Decay

Tree assessment methodologies, currently used to evaluate the structural stability of individual urban trees, usually involve a visual analysis followed by measurements of the internal soundness of wood using various instruments that are often invasive, expensive, or inadequate for use within the urban environment. Moreover, most conventional instruments do not provide an adequate evaluation of decay that occurs in the root system. The intent of this research was to evaluate the possibility of integrating conventional tools, currently used for assessments of decay in urban trees, with the electronic nose–a new innovative tool used in diverse fields and industries for various applications such as quality control in manufacturing, environmental monitoring, medical diagnoses, and perfumery. Electronic-nose (e-nose) technologies were tested for the capability of detecting differences in volatile organic compounds (VOCs) released by wood decay fungi and wood from healthy and decayed trees. Three e-noses, based on different types of operational technologies and analytical methods, were evaluated independently (not directly compared) to determine the feasibility of detecting incipient decays in artificially-inoculated wood. All three e-nose devices were capable of discriminating between healthy and artificially-inoculated, decayed wood with high levels of precision and confidence. The LibraNose quartz microbalance (QMB) e-nose generally provided higher levels of discrimination of sample unknowns, but not necessarily more accurate or effective detection than the AromaScan A32S conducting polymer and PEN3 metal-oxide (MOS) gas sensor e-noses for identifying and distinguishing woody samples containing different agents of wood decay. However, the conducting polymer e-nose had the greater advantage for identifying unknowns from diverse woody sample types due to the associated software capability of utilizing prior-developed, application-specific reference libraries with aroma pattern-recognition and neural-net training algorithms.

[1]  Yan Gao,et al.  Volatile Organic Compounds and Their Roles in Bacteriostasis in Five Conifer Species , 2005 .

[2]  Simona Benedetti,et al.  Electronic nose as a non-destructive tool to characterise peach cultivars and to monitor their ripening stage during shelf-life , 2008 .

[3]  Anna-Karin Borg-Karlson,et al.  Influence of Fungal Infection and Wounding on Contents and Enantiomeric Compositions of Monoterpenes in Phloem of Pinus sylvestris , 2006, Journal of Chemical Ecology.

[4]  A. D. Wilson,et al.  Development of conductive polymer analysis for the rapid detection and identification of phytopathogenic microbes. , 2004, Phytopathology.

[5]  Lynne Boddy,et al.  Fungal decomposition of wood. Its biology and ecology. , 1988 .

[6]  V. Kosma,et al.  Sensory irritating potency of some microbial volatile organic compounds (MVOCs) and a mixture of five MVOCs. , 1999, Archives of environmental health.

[7]  Lynne Boddy,et al.  Fungal decomposition of wood , 1988 .

[8]  Helge Breloer,et al.  FIELD GUIDE FOR VISUAL TREE ASSESSMENT (VTA) , 1994 .

[9]  G. Sauerbrey,et al.  Use of quartz vibration for weighing thin films on a microbalance , 1959 .

[10]  Harold H. Burdsall,et al.  Preserving cultures of wood-decaying Basidiomycotina using sterile distilled water in cryovials , 1994 .

[11]  E. Thomas Smiley,et al.  Hazard Tree Inspection, Evaluation, and Management , 2007 .

[12]  S. Gravesen,et al.  Health implications of fungi in indoor environments. , 1994 .

[13]  G. Sauerbrey.  Verwendung von Schwingquarzen zur Wägung dünner Schichten und zur Mikrowägung , 1959 .

[14]  D. G. Lester,et al.  Application of conductive polymer analysis for wood and woody plant identifications , 2005 .

[15]  Alphus D. Wilson,et al.  Applications and Advances in Electronic-Nose Technologies , 2009, Sensors.

[16]  Russell K. Monson,et al.  Reduction of isoprene emissions from live oak (Quercus fusiformis) with oak wilt. , 2000, Tree physiology.

[17]  N. Magan,et al.  Volatiles as an indicator of fungal activity and differentiation between species, and the potential use of electronic nose technology for early detection of grain spoilage. , 2000, Journal of stored products research.

[18]  John E. Kuser,et al.  Urban and community forestry in the northeast , 2007 .

[19]  N. Ratcliffe,et al.  Identification by gas chromatography-mass spectrometry of the volatile organic compounds emitted from the wood-rotting fungi Serpula lacrymans and Coniophora puteana, and from Pinus sylvestris timber. , 2004, Mycological research.

[20]  Randal S. Martin,et al.  Biogenic emissions and ambient concentrations of hydrocarbons, carbonyl compounds and organic acids from ponderosa pine and cottonwood trees at rural and forested sites in Central New Mexico , 2004 .

[21]  Francesco Ferrini,et al.  Evaluation of the diagnostic feasibility of the electronic nose in detecting incipient decay of artificially inoculated wood , 2008 .

[22]  Richard J. Ewen,et al.  Sensors for early warning of post-harvest spoilage in potato tubers , 2002 .