Guignardia aesculi (Peck) V.B. Stewart
(Horse Chestnut Leaf Blotch - causative organism)

Taxonomic hierarchy:
SpeciesGuignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
GenusGuignardia (a genus of ascomycete fungi)
FamilyPHYLLOSTICTACEAE (a family of fungi)
OrderBOTRYOSPHAERIALES (an order of ascomycetes)
ClassDOTHIDEOMYCETES (a class of ascomycetes)
SubphylumPEZIZOMYCOTINA (a subphylum of ascomycetes)
PhylumASCOMYCOTA (spore shooters, ascomycete)
KingdomFUNGI (true fungi)
DomainEukaryota (eukaryotes)
LifeBIOTA (living things)
Records of Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism) :
1: Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
7 Jul 2008 OSGR: SK38 53° 20’ N, 1° 30’ W Vice County: South-west Yorks (VC 63) England
on chestnut leaves, following period of damp weather
Image 1: Fertile leaf-spot - magnifiedImage 2: Fertile leaf-spot - magnified (2)Image 3: Fertile leaf-spot - magnified (3)Image 4: Fertile leaf-spot - magnified (4)Image 5: Fertile leaf-spot - magnified (5)Image 6: Fertile leaf-spot - magnified (6)Image 7: Fertile leaf-spot - top surface - close-up - enlargedImage 8: Fertile leaf-spot - top surface - close-up - enlarged (2)Image 9: Fertile leaf-spot - top surface - enlargedImage 10: Fertile leaf-spot - top surface - enlarged (2)Image 11: Fertile leaf-spot - top surface - enlarged (3)Image 12: Fertile leaf-spot - top surface - enlarged (4)Image 13: Fertile leaf-spot - under surface - close-up - enlargedImage 14: Fertile leaf-spot - under surface - enlargedImage 15: Sterile leaf-spot - top surface - enlargedImage 16: Conidia - magnifiedImage 17: Conidia - magnified (2)Image 18: Conidia - highly magnifiedImage 19: Conidia - highly magnified (2)Image 20: Conidia - highly magnified (3)Image 21: Conidia - highly magnified (4)Image 22: Conidia - highly magnified (5)Image 23: Conidia - highly magnified (6)Image 24: Pycnidia in squash prep. - microscope low magnificationImage 25: Pycnidial wall and conidia - magnifiedImage 26: Pycnidium in squash prep. - magnifiedImage 27: Pycnidium in squash prep. - magnified (2)
2: Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
5 Sep 2007 OSGR: SK38 53° 20’ N, 1° 30’ W Vice County: South-west Yorks (VC 63) England
on horse chestnut
Image 1: Infected leafImage 2: Infected leaf (2)Image 3: Infected leaf - close-upImage 4: Infected leavesImage 5: Leaf spots - top surface - close-upImage 6: Leaf spots - top surface - close-up (2)Image 7: Leaf spots - top surface - close-up (3)Image 8: Infected leaf - top surface - close-up - magnifiedImage 9: Infected leaf - top surface - close-up - magnified (2)Image 10: Infected leaf - top surface - close-up - magnified (3)Image 11: Infected leaf - top surface - close-up - magnified (4)Image 12: Infected leaf - top surface - close-up - magnified (5)Image 13: Infected leaf - top surface - close-up - magnified (6)Image 14: Infected leaf - top surface - close-up - magnified (7)Image 15: Infected leaf - under surface - close-up - magnifiedImage 16: Infected leaf - under surface - close-up - magnified (2)Image 17: Infected leaf - under surface - close-up - magnified (3)Image 18: Infected leaf - under surface - close-up - magnified (4)Image 19: Infected leaf - under surface - close-up - magnified (5)Image 20: Infected leaf - under surface - close-up - magnified (6)Image 21: Infected leaf - under surface - close-up - magnified (7)Image 22: Infected leaf - under surface - close-up - magnified (8)Image 23: Infected leaf - under surface - close-up - magnified (9)Image 24: Leaf spots - top surface - close-up - enlargedImage 25: Leaf spots - under surface - close-up - enlargedImage 26: Leaf spots - under surface - close-up - enlarged (2)Image 27: Leaf spots - under surface - close-up - enlarged (3)Image 28: Leaf spots - under surface - close-up - enlarged (4)Image 29: Pycnidia in leaf spot on top surface of leaf - magnifiedImage 30: Pycnidia in leaf spot on top surface of leaf - magnified (2)Image 31: Pycnidia in leaf spot on top surface of leaf - magnified (3)Image 32: Pycnidia in leaf spot on top surface of leaf - magnified (4)Image 33: Conidia - highly magnifiedImage 34: Pycnidium squash - magnified
3: Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
11 Jul 1998 OSGR: SU88 51° 30’ N, 0° 50’ W Vice County: Bucks (VC 24) England
leaf spots on Horse Chestnut
Image 1: Infected leaflet - uppersideImage 2: Infected leaflet - undersideImage 3: Infection on leaf uppersideImage 4: Infection on leaf upperside - close-upImage 5: Infection on leaf undersideImage 6: Infection on leaf underside - close-up

Identification Works

AuthorYearTitleSource
Forest Research 2007 Path News Issue 15: October 2007
Forest Research 2004 Path News Issue 8: July 2004
Hudson, H.J. 1987 Guignardia leaf blotch of Horsechestnut TBMS Vol 89 (3): 400-401.
Punithalingam, E. 1993 Guignardia aesculi I.M.I. Descriptions of Pathogenic Fungi and Bacteria CMI Descriptions of Pathenogenic Fungi and Bacteria Sheet 1165.

Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism) may also be included in identification literature listed under the following higher taxa:

NBNNBN (data.nbn.org.uk) has a distribution map for Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
BioInfoBioInfo (www.bioinfo.org.uk) has 8 host/parasite/foodplant and/or other relationships for Guignardia aesculi (Horse Chestnut Leaf Blotch - causative organism)
Creative Commons License
This website is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International Licence.

Unless otherwise expressly stated, all original material on the BioImages website by Malcolm Storey is licensed under the above Creative Commons Licence.

Photographs from other photographers are used with permission but not included under the above CC licence.

BioImages - Virtual Field-Guide (UK)