Etienne Yergeau

Assistant Professor,
INRS-Institut Armand-Frappier

Institution page


  • Doctorate, Ph.D., Microbial Ecology, Free University, Amsterdam - Vrije Universiteit, 2004/6 - 2008/6
  • Master's Thesis, M.Sc., Sciences Biologiques, Université de Montréal, 2002/6 - 2004/6
  • Bachelor's, B.Sc., Sciences Biologiques, Université de Montréal, 1999/9 - 2002/6


The vision of "Le Labo Yergeau" is that the plant microbiome can be reengineered to promote plant health and productivity. As such, plant microbiome engineering is likely to generate solutions to many real-life problems like climate change, contaminated soils and declining food production. In the mid-term, our research program aim at finding new approaches to purposefully, reliably, and sustainably enhance the beneficial rhizosphere microbiome of important crops.

QCBS students


(Start: 2018, End: 2021)
Design of synthetic microbial communities to improve wheat holobiont resistance to eater stress

Anne de la Porte

(Start: 2017, End: 2021)
Other QCBS (co-)supervisor: Philippe Constant
Caractérisation des restructurations taxonomiques et fonctionnelles spécifiquement induites par le statut Hup- du pois Pisum sativum dans la rhizosphère et détermination de l'effet rétroactif du sol a

Jessica Dozois

(Start: 2019, End: 2021)
Plant-microbiome interactions: importance of miRNAs regarding nitrogen acquisition

Previous students (since 2009)

Hamed Azarbad

Postdoctoral fellow
(Start: 2016, End: 2017)
The impacts of abiotic stresses on the nitrogen-cycle functions in the wheat rhizosphere
Personal page

Usman Irshad

Postdoctoral fellow
(Start: 2016, End: 2016)
prey-predator interactions (bacteria and nematodes) in wheat roots and growth hormones

Ruth Schmidt

Postdoctoral fellow
(Start: 2018, End: 2020)
Novel holobiont-based approaches to rapidly adapt wheat to drought stress
Link to thesis (pdf)
Personal page

Itumeleng Moroenyane

(Start: 2016, End: 2020)
Microbial assembly rules of the plant microbiome: insights for plant micro biome engineering
Personal page

Liliana Quiza

(Start: 2016, End: 2020)
Other QCBS (co-)supervisor: Marc St-Arnaud
Engineering wheat rhizosphere microbiome to increase its capacity to assimilate Nitrogen

Examples of species studied

Carex arenaria
Festuca rubra
Salix purpurea
Campylobacter jejuni


86- Hydrocarbon substrate richness impacts microbial abundance, microbiome composition, and hydrocarbon loss
Bell T H , Camillone N , Abram K , Bruns M A , Yergeau E , St-Arnaud M ,
2021 Applied Soil Ecology (Date Added: 2021-04-22)

85- Soil Characteristics Constrain the Response of Microbial Communities and Associated Hydrocarbon Degradation Genes during Phytoremediation
Correa-García S , Rheault K , Tremblay J , Séguin A , Yergeau E ,
2021 Applied and environmental microbiology (Date Added: 2021-01-27)

82- Rhizospheric Plant–Microbe Interactions: miRNAs as a Key Mediator
2020 Trends in Plant Science (Date Added: 2020-12-19)

80- Four decades of soil water stress history together with host genotype constrain the response of the wheat microbiome to soil moisture
Azarbad H , Tremblay J , Giard-Laliberté C , Bainard L D , Yergeau E ,
2020 FEMS microbiology ecology (Date Added: 2020-07-03)

79- A Gaseous Milieu: Extending the Boundaries of the Rhizosphere
de la Porte A , Schmidt R , Yergeau ,
2020 Trends in Microbiology (Date Added: 2020-03-31)

78- Microbial indicators are better predictors of wheat yield and quality than N fertilization
Yergeau ,
2020 FEMS microbiology ecology (Date Added: 2020-02-02)

77- Systematic processing of ribosomal RNA gene amplicon sequencing data
Tremblay J , Yergeau E ,
2019 GigaScience (Date Added: 2019-12-24)

76- Manipulating wild and tamed phytobiomes: Challenges and opportunities
Bell T H , Hockett K L , Alcalá-Briseño R I , Barbercheck M , Beattie G A , Bruns M A , Carlson J E , Chung T , Collins A , Emmett B , Esker P , Garrett K A , Glenna L , Gugino B K , Jiménez-Gasco M d M , Kinkel L , Kovac J , Kowalski K P , Kuldau G , Leveau J H J , Michalska-Smith M J , Myrick J , Peter K , Salazar M F V , Shade A , Stopnisek N , Tan X , Welty A T , Wickings K , Yergeau E ,
2019 Phytobiomes Journal (Date Added: 2019-08-25)

75- A water stress-adapted inoculum affects rhizosphere fungi, but not bacteria nor wheat
Giard-Laliberté C , Azarbad H , Tremblay J , Bainard L , Yergeau ,
2019 FEMS microbiology ecology (Date Added: 2019-07-11)

74- Salmonella shedding status of the sow affects the microbiota of their piglets at weaning
Larivière-Gauthier G , Thibodeau A , Letellier A , Yergeau ,
2018 Journal of Applied Microbiology (Date Added: 2018-12-04)

73- Water stress history and wheat genotype modulate rhizosphere microbial response to drought
Azarbad H , Constant P , Giard-Laliberté C , Bainard L D , Yergeau E ,
2018 Soil Biology and Biochemistry (Date Added: 2018-10-22)

72- Bacterial subspecies variation and nematode grazing change P dynamics in the wheat rhizosphere
Irshad U , Yergeau E ,
2018 Frontiers in Microbiology (Date Added: 2018-09-21)

71- Serratia marcescens outbreak in a neonatal intensive care unit: New insights from next-generation sequencing applications
Martineau C , Li X , Lalancette C , Perreault T , Fournier E , Tremblay J , Gonzales M , Yergeau ,
2018 Journal of Clinical Microbiology (Date Added: 2018-09-10)

70- Rhizoremediation of petroleum hydrocarbons: a model system for plant microbiome manipulation
Correa-García S , Pande P , Séguin A , St-Arnaud M , Yergeau E ,
2018 Microbial Biotechnology (Date Added: 2018-09-04)

69- Canola root-Associated microbiomes in the Canadian Prairies
Lay C , Bell T H , Hamel C , Harker K N , Mohr R , Greer C W , Yergeau ,
2018 Frontiers in Microbiology (Date Added: 2018-06-21)

68- The impact of reconstructed soils following oil sands exploitation on aspen and its associated belowground microbiome
Stefani, F, Isabel, N, Morency, M-J, Lamothe, M, Nadeau, S, Lachance, D, Li, EHY, Greer, C, Yergeau, E, Pinno, BD, Seguin, A
2018 Scientific Reports (Date Added: 2018-05-23)

67- Trees, fungi and bacteria: Tripartite metatranscriptomics of a root microbiome responding to soil contamination
Gonzalez E , Pitre F E , Pagé A P , Marleau J , Guidi Nissim W , St-Arnaud M , Labrecque M , Joly S , Yergeau E , Brereton N J B ,
2018 Microbiome (Date Added: 2018-04-04)

66- Soil contamination alters the willow root and rhizosphere metatranscriptome and the root-rhizosphere interactome
Yergeau E , Tremblay J , Joly S , Labrecque M , Maynard C , Pitre F E , St-Arnaud M , Greer C W ,
2018 ISME Journal (Date Added: 2018-03-30)

65- Chemical dispersants enhance the activity of oil- and gas condensate-degrading marine bacteria
Tremblay J , Yergeau E , Fortin N , Cobanli S , Elias M , King T L , Lee K , Greer C W ,
2017 ISME Journal (Date Added: 2017-12-06)

64- Reduction of Salmonella Shedding by sows during gestation in relation to its fecal microbiome
Larivière-Gauthier G , Thibodeau A , Letellier A , Yergeau ,
2017 Frontiers in Microbiology (Date Added: 2017-12-01)

63- Editorial: Signaling in the phytomicrobiome
Smith D L , Gravel V , Yergeau E ,
2017 Frontiers in Plant Science (Date Added: 2017-05-10)

61- Metagenomic survey of the taxonomic and functional microbial communities of seawater and sea ice from the Canadian Arctic
Yergeau E , Michel C , Tremblay J , Niemi A , King T L , Wyglinski J , Lee K , Greer C W ,
2017 Scientific Reports (Date Added: 2017-02-24)

60- Feed presentation options in Swine early fattening mitigates Salmonella shedding and specifically modulates the faecal microbiota
Lebel P , Letellier A , Longpré J , Laplante B , Yergeau E , Fravalo P ,
2017 Journal of Applied Microbiology (Date Added: 2017-02-15)

59- A Diverse Soil Microbiome Degrades More Crude Oil than Specialized Bacterial Assemblages Obtained in Culture
Bell, TH, Stefani, FOP, Abram, K, Champagne, J, Yergeau, E, Hijri, M, St-Arnaud, M
2016 Applied and Environmental Microbiology (Date Added: 2016-11-28)

58- The willow microbiome is influenced by soil petroleum-hydrocarbon concentration with plant compartment-specific effects
Tardif, S, Yergeau, , Tremblay, J, Legendre, P, Whyte, LG, Greer, CW
2016 Frontiers in Microbiology (Date Added: 2016-11-28)

57- Comparison of Methods to Identify Pathogens and Associated Virulence Functional Genes in Biosolids from Two Different Wastewater Treatment Facilities in Canada
Yergeau, E, Masson, L, Elias, M, Xiang, S, Madey, E, Huang, H, Brooks, B, Beaudette, LA
2016 PloS one (Date Added: 2016-08-05)

55- Transplanting Soil Microbiomes Leads to Lasting Effects on Willow Growth, but not on the Rhizosphere Microbiome
Yergeau, E, Bell, TH, Champagne, J, Maynard, C, Tardif, S, Tremblay, J, Greer, CW
2015 Frontiers in Microbiology (Date Added: 2016-02-05)

54- Diversity and complexity of microbial communities from a chlor-alkali tailings dump
Zappelini, C, Karimi, B, Foulon, J, Lacercat-Didier, L, Maillard, F, Valot, B, Blaudez, D, Cazaux, D, Gilbert, D, Yergeau, E, Greer, C, Chalot, M
2015 Soil Biology and Biochemistry (Date Added: 2016-01-21)

53- "Omics" Insights into PAH Degradation toward Improved Green Remediation Biotechnologies
El Amrani, A, Dumas, A-S, Wick, LY, Yergeau, E, Berthomé, R
2015 Environmental Science and Technology (Date Added: 2016-01-21)

52- Chicken Caecal Microbiome modifications induced by campylobacter Jejuni colonization and by a non-antibiotic feed additive
Thibodeau, A, Fravalo, P, Yergeau, E, Arsenault, J, Lahaye, L, Letellier, A
2015 PLoS ONE (Date Added: 2016-01-21)

51- Microbial community composition, functions, and activities in the gulf of mexico 1 year after the deepwater horizon accident
Yergeau, E, Maynard, C, Sanschagrin, S, Champagne, J, Juck, D, Lee, K, Greer, CW
2015 Applied and Environmental Microbiology (Date Added: 2016-01-21)

50- Metaproteomics of aquatic microbial communities in a deep and stratified estuary
Colatriano, D, Ramachandran, A, Yergeau, E, Maranger, R, Gélinas, Y, Walsh, DA
2015 Proteomics (Date Added: 2016-01-21)

49- Importance of Rhodococcus strains in a bacterial consortium degrading a mixture of hydrocarbons, gasoline, and diesel oil additives revealed by metatranscriptomic analysis
Auffret, MD, Yergeau, E, Labbé, D, Fayolle-Guichard, F, Greer, CW
2015 Applied Microbiology and Biotechnology (Date Added: 2016-01-21)

48- Harnessing phytomicrobiome signaling for rhizosphere microbiome engineering
Quiza, L, St-Arnaud, M, Yergeau, E
2015 Frontiers in Plant Science (Date Added: 2015-08-26)

47- Early rhizosphere microbiome composition is related to the growth and Zn uptake of willows introduced to a former landfill
Bell, TH, Cloutier-Hurteau, B, Al-Otaibi, F, Turmel, M-C, Yergeau, E, Courchesne, F, St-Arnaud, M
2015 Environmental Microbiology (Date Added: 2015-08-26)

46- Microbial functional potential and community composition in permafrost-affected soils of the NW Canadian Arctic
Frank-Fahle, BA, Yergeau, E, Greer, CW, Lantuit, H, Wagner, D
2014 PloS one (Date Added: 2016-02-05)

45- Biogeochemical activity of microbial biofilms in the water column overlying uranium mine tailings
Bondici, VF, Khan, NH, Swerhone, GDW, Dynes, JJ, Lawrence, JR, Yergeau, E, Wolfaardt, GM, Warner, J, Korber, DR
2014 Journal of Applied Microbiology (Date Added: 2016-02-05)

44- Bacterial community structure and soil properties of a subarctic tundra soil in Council, Alaska
Kim, HM, Jung, JY, Yergeau, E, Hwang, CY, Hinzman, L, Nam, S, Hong, SG, Kim, O-S, Chun, J, Lee, YK
2014 FEMS Microbiology Ecology (Date Added: 2016-01-21)

43- Atmospheric methane oxidizers are present and active in Canadian high Arctic soils
Martineau, C, Pan, Y, Bodrossy, L, Yergeau, E, Whyte, LG, Greer, CW
2014 FEMS Microbiology Ecology (Date Added: 2016-01-21)

42- Fell-field soil microbiology
Yergeau, E
2014 Antarctic Terrestrial Microbiology: Physical and Biological Properties of Antarctic Soils (Date Added: 2016-01-21)

41- Climate change and microbial populations
Yergeau, E
2014 Antarctic Terrestrial Microbiology: Physical and Biological Properties of Antarctic Soils (Date Added: 2016-01-21)

40- Increasing phytoremediation efficiency and reliability using novel omics approaches
Bell, TH, Joly, S, Pitre, FE, Yergeau, E
2014 Trends in Biotechnology (Date Added: 2014-04-29)

39- Microbial expression profiles in the rhizosphere of willows depend on soil contamination
Yergeau, E, Sanschagrin, S, Maynard, C, St-Arnaud, M, Greer, CW
2014 ISME Journal (Date Added: 2013-10-30)

38- Linkage between bacterial and fungal rhizosphere communities in hydrocarbon-contaminated soils is related to plant phylogeny
Bell, TH, El-Din Hassan, S, Lauron-Moreau, A, Al-Otaibi, F, Hijri, M, Yergeau, E, St-Arnaud, M
2014 ISME Journal (Date Added: 2013-09-09)

37- Aerobic biofilms grown from Athabasca watershed sediments are inhibited by increasing concentrations of bituminous compounds
Yergeau, E, Lawrence, JR, Sanschagrin, S, Roy, JL, Swerhone, GDW, Korber, DR, Greer, CW
2013 Applied and Environmental Microbiology (Date Added: 2016-02-05)

36- Alteration of microbial community structure affects diesel biodegradation in an Arctic soil
Bell, TH, Yergeau, E, Juck, DF, Whyte, LG, Greer, CW
2013 FEMS Microbiology Ecology (Date Added: 2016-01-21)

35- Plant and Bird Presence Strongly Influences the Microbial Communities in Soils of Admiralty Bay, Maritime Antarctica
Teixeira, LCRS, Yeargeau, E, Balieiro, FC, Piccolo, MC, Peixoto, RS, Greer, CW, Rosado, AS
2013 PLoS ONE (Date Added: 2016-01-21)

34- Microbial communities in low permeability, high pH uranium mine tailings: Characterization and potential effects
Bondici, VF, Lawrence, JR, Khan, NH, Hill, JE, Yergeau, E, Wolfaardt, GM, Warner, J, Korber, DR
2013 Journal of Applied Microbiology (Date Added: 2016-01-21)

33- Increased microbial activity and nitrogen mineralization coupled to changes in microbial community structure in the rhizosphere of Bt corn
Velasco, AGV, Kowalchuk, GA, Mañero, FJG, Ramos, B, Yergeau, E, García, JAL
2013 Applied Soil Ecology (Date Added: 2016-01-21)

32- Predictable bacterial composition and hydrocarbon degradation in Arctic soils following diesel and nutrient disturbance
Bell, TH, Yergeau, E, Maynard, C, Juck, D, Whyte, LG, Greer, CW
2013 ISME Journal (Date Added: 2016-01-21)

31- Impact of water quality on the bacterial populations and off-flavours in recirculating aquaculture systems
Auffret, M, Yergeau, E, Pilote, A, Proulx, E, Proulx, D, Greer, CW, Vandenberg, G, Villemur, R
2013 FEMS Microbiology Ecology (Date Added: 2016-01-21)

30- Defining the functional potential and active community members of a sediment microbial community in a high-arctic hypersaline subzero spring
Lay, C-Y, Mykytczuk, NCS, Yergeau, , Lamarche-Gagnon, G, Greer, CW, Whyte, LG
2013 Applied and Environmental Microbiology (Date Added: 2016-01-21)

29-Metagenomics potential for bioremediation. In Nelson KE (ed) Encyclopedia of Metagenomics. doi: 10.1007/SpringerReference_303987.
Bell TH, GC
2012 ( Date Added: 2016-02-05)

28-Quantification of microorganisms using a functional gene approach, pp 107-120. In Filion M (ed) Quantitative Real-time PCR in Applied Microbiology. Horizon Scientific Press, Norwich, UK. ISBN: 978-1-908230-01-0.
Teixeira LCRS, YE
2012 ( Date Added: 2016-02-05)

27-Metagenomic analysis of polar ecosystems, pp 156–165. In Miller RV, Whyte LG (eds) Polar Microbiology: Life in a Deep Freeze. ASM Press, Washington, DC, USA. ISBN: 978-1-55581-604-9.
Yergeau E, GC
2012 ( Date Added: 2016-02-05)

26- Sub-inhibitory concentrations of different pharmaceutical products affect the meta-transcriptome of river biofilm communities cultivated in rotating annular reactors
Yergeau, E, Sanschagrin, S, Waiser, MJ, Lawrence, JR, Greer, CW
2012 Environmental Microbiology Reports (Date Added: 2016-02-05)

25- Next-generation sequencing of microbial communities in the athabasca river and its tributaries in relation to oil sands mining activities
Yergeau, E, Lawrence, JR, Sanschagrin, S, Waiser, MJ, Korber, DR, Greer, CW
2012 Applied and Environmental Microbiology (Date Added: 2016-01-21)

24- Shifts in soil microorganisms in response to warming are consistent across a range of Antarctic environments
Yergeau, E, Bokhorst, S, Kang, S, Zhou, J, Greer, CW, Aerts, R, Kowalchuk, GA
2012 ISME Journal (Date Added: 2016-01-21)

23- Community patterns of soil bacteria and nematodes in relation to geographic distance
Monroy, F, van der Putten, WH, Yergeau, E, Mortimer, SR, Duyts, H, Bezemer, TM
2012 Soil Biology and Biochemistry (Date Added: 2016-01-21)

22- Metagenomic analysis of the bioremediation of diesel-contaminated canadian high arctic soils
Yergeau, E, Sanschagrin, S, Beaumier, D, Greer, CW
2012 PLoS ONE (Date Added: 2016-01-21)

21- Soil characteristics more strongly influence soil bacterial communities than land-use type
Kuramae, EE, Yergeau, E, Wong, LC, Pijl, AS, Van Veen, JA, Kowalchuk, GA
2012 FEMS Microbiology Ecology (Date Added: 2016-01-21)

20- Identification of nitrogen-incorporating bacteria in petroleum-contaminated arctic soils by using [ 15N]DNA-based stable isotope probing and pyrosequencing
Bell, TH, Yergeau, E, Martineau, C, Juck, D, Whyte, LG, Greer, CW
2011 Applied and Environmental Microbiology (Date Added: 2016-01-21)

19-Plant-associated microbial communities, pp 131–148. In Jansson JK, Liu W-T (eds) Environmental Molecular Microbiology. Horizon Scientific Press, Norwich, UK. ISBN: 978-1-904455-52-3.
Kowalchuk GA, YE
2010 ( Date Added: 2016-02-05)

18- Metatranscriptomic analysis of the response of river biofilms to pharmaceutical products, using anonymous DNA microarrays
Yergeau, E, Lawrence, JR, Waiser, MJ, Korber, DR, Greer, CW
2010 Applied and Environmental Microbiology (Date Added: 2016-02-05)

17- Patterns of Fusarium community structure and abundance in relation to spatial, abiotic and biotic factors in soil
Yergeau, E, Labour, K, Hamel, C, Vujanovic, V, Nakano-Hylander, A, Jeannotte, R, St-Arnaud, M
2010 FEMS Microbiology Ecology (Date Added: 2016-02-05)

16- The functional potential of high Arctic permafrost revealed by metagenomic sequencing, qPCR and microarray analyses
Yergeau, E, Hogues, H, Whyte, LG, Greer, CW
2010 ISME Journal (Date Added: 2016-01-21)

15- Influences of space, soil, nematodes and plants on microbial community composition of chalk grassland soils
Yergeau, E, Bezemer, TM, Hedlund, K, Mortimer, SR, Kowalchuk, GA, van der Putten, WH
2010 Environmental Microbiology (Date Added: 2016-01-21)

14- Microbial secondary succession in a chronosequence of chalk grasslands
Kuramae, EE, Gamper, HA, Yergeau, E, Piceno, YM, Brodie, EL, Desantis, TZ, Andersen, GL, Van Veen, JA, Kowalchuk, GA
2010 ISME Journal (Date Added: 2016-01-21)

13- Environmental microarray analyses of Antarctic soil microbial communities
Yergeau, E, Schoondermark-Stolk, SA, Brodie, EL, Dejean, S, DeSantis, TZ, Goncalves, O, Piceno, YM, Andersen, GL, Kowalchuk, GA
2009 The ISME Journal (Date Added: 2016-02-05)

12- Temperature adaptation of soil bacterial communities along an Antarctic climate gradient: Predicting responses to climate warming
Rinnan, R, Rousk, J, Yergeau, E, Kowalchuk, GA, Bååth, E
2009 Global Change Biology (Date Added: 2016-01-21)

11- Microarray and real-time PCR analyses of the responses of high-arctic soil bacteria to hydrocarbon pollution and bioremediation treatments
Yergeau, E, Arbour, M, Brousseau, R, Juck, D, Lawrence, JR, Masson, L, Whyte, LG, Greer, CW
2009 Applied and Environmental Microbiology (Date Added: 2016-01-21)

10- Responses of Antarctic soil microbial communities and associated functions to temperature and freeze-thaw cycle frequency
Yergeau, E, Kowalchuk, GA
2008 Environmental Microbiology (Date Added: 2016-02-05)

9- Impact of elevated carbon dioxide on the rhizosphere communities of Carex arenaria and Festuca rubra
Drigo, B, Kowalchuk, GA, Yergeau, E, Bezemer, TM, Boschker, HTS, Van Veen, JA
2007 Global Change Biology (Date Added: 2016-01-21)

8- Patterns of bacterial diversity across a range of Antarctic terrestrial habitats
Yergeau, E, Newsham, KK, Pearce, DA, Kowalchuk, GA
2007 Environmental Microbiology (Date Added: 2016-01-21)

7- Functional microarray analysis of nitrogen and carbon cycling genes across an Antarctic latitudinal transect
Yergeau, E, Kang, S, He, Z, Zhou, J, Kowalchuk, GA
2007 ISME Journal (Date Added: 2016-01-21)

6- Size and structure of bacterial, fungal and nematode communities along an Antarctic environmental gradient
Yergeau, E, Bokhorst, S, Huiskes, AHL, Boschker, HTS, Aerts, R, Kowalchuk, GA
2007 FEMS Microbiology Ecology (Date Added: 2016-01-21)

5-Assessing bacterial and fungal community structure in soil using ribosomal RNA and other structural gene markers, pp 159–188. In Nannipieri N, Smalla K (eds) Nucleic acids and proteins in soil. Springer-Verlag, Berlin. ISBN: 3-540-29448-1
Kowalchuk GA, DB
2006 ( Date Added: 2016-02-05)

4- Relationships between Fusarium population structure, soil nutrient status and disease incidence in field-grown asparagus
Yergeau, E, Sommerville, DW, Maheux, E, Vujanovic, V, Hamel, C, Whalen, JK, St-Arnaud, M
2006 FEMS Microbiology Ecology (Date Added: 2011-04-14)

3- Changes in communities of Fusarium and arbuscular mycorrhizal fungi as related to different asparagus cultural factors
Yergeau, E, Vujanovic, V, St-Arnaud, M
2006 Microbial Ecology (Date Added: 2011-04-14)

1- A PCR-denaturing gradient gel electrophoresis approach to assess Fusarium diversity in asparagus
Yergeau, E, Filion, M, Vujanovic, V, St-Arnaud, M
2005 Journal of Microbiological Methods (Date Added: 2011-04-14)