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Lifestyles of Colletotrichumand implications for
anthracnose integrated disease management
Paul Taylor
Professor of Plant Pathology
University of Melbourne
Outline
• Introduction to anthracnose caused by Colletotrichum spp and problems with control
• Lifestyles of Colletotrichum spp
• Current taxonomy of species
• Colletotrichum spp infecting chili in SE Asia
• Pathogenicity of species infecting chili
Anthracnose• Important disease affecting wide
range of plant species• Crop, orchard and post harvest
disease and maybe seed transmitted
• Biosecurity risk to importers and producers
C. siamense
C. scovillei
C. truncatum
C. gloeosporioidesC. acutatum, C. fruticola
Control of anthracnose caused by Colletotrichum spp.
• Difficult disease to control because:
– Pathogen may infect a wide host range
– Difficult to identify species
– Variable lifestyles of species during infection
– Lack of progress in identifying resistant genes
– Development of pathotypes within species
– Fungicide resistance
Life styles of Colletotrichum
• Important to understand the mechanism of infection and colonisation by Colletotrichumspecies
– major implications in the global transmission of the pathogens (biosecurity risk)
– the implementation of integrated disease control methods
General life cycle of Colletotrichumspecies
De Silva et al. (2017). Fungal Biology Reviews
Life styles of Colletotrichum
• Necrotrophic – infect and kill host tissue and extract nutrients from the dead host cells
• Hemibiotrophic – colonize living plant tissue and obtain nutrients from living host cells before moving to a necrotrophic life style
• Endophytic - lives within a plant for at least part of its life without causing apparent disease
• Latent or Quiescent –an inactive or dormant phase within an infected cell
C. truncatum in chili fruit –hemibiotrophic/necrotrophic/latent
Fungal transformation
using the green
fluorescent protein (GFP)
Auyong et al. (2012). Journal of Basic Microbiology
Intramural colonization
Hemibiotrophic colonisation - hyphae infect tissue by colonisingcell walls then changes to infect and kill cells (necrotrophic)
cu
epcu
ep
Necrotrophic infection
Latent infection on chili leaves
Leaves symptomless until senescence 5 weeks after inoculation at 103 spores/mL
10 μm
C
AP
GT
(A)
10 μm
IH
AP
(B)
Spore germination and appressoria12 h
Infection of leaves –intramural hyphaebeneath cuticle48 h
Ranathunge et al. (2012) Australasian Plant Pathology
Disease cycle of Colletotrichum truncatum
Sexual
Reproduction
?Crop
debris
C. truncatum infected fruits
Acervuli
formation
Seed infection
Water splash
dispersal of conidia
Infection of young
plants and seedlings
Pre- and post
emergent
infectionWater
splash
dispersal
of conidia
Leaf infection and quiescence
Colletotrichum lentis in lentil –hemibiotrophic/necrotrophic
http://www.agriculture.gov.sk.ca/
• Formation of multiseptate, multilobed vesicle in the epidermal cell
• Typical of the destructivum complex
Colletotrichum coccodes in potatoes - endophytic/necrotrophic
• Black dot –microsclerotia on tuber peel
• Infects by appressoria, then colonises entire plant via vascular system.
• After 12 weeks the roots and stolon tissue colonised
Appressoria formation and leaf infection
Is C. coccodes a plant pathogen?
Necrotic leaf lesion after inoculation with 106
spores/mL
Necrotic lesions on chili fruit 9 days after inoculation of wounded chili fruit
Problems with Colletotrichum taxonomy
• Lack of reliable morphological features
• Pathogenic variation
• Many older Colletotrichum names lack
type specimens and living strains for
molecular analysis
Type specimen of C. capsici 1912, now called C. truncatum
Molecular taxonomy of fungi
Fungal gene sequences
– ITS rDNA
– partial b-tubulin
– translation elongation factor 1-α
– glutamine synthetase
– glyceraldehyde 3-phosphate dehydrogenase
– actin
– histone
– mating type genes (ApMAT)
Nuclear small rDNA (18S) ITS5.8S
rDNA ITS Nuclear large rDNA (25S)
ITS4
ITS5 ITS1 ITS3
ITS2
Determine phylogenetic relationship between
species – based on sequence similarity
Taxonomy of Colletotrichum 2012
Jayawardena et al (2016). Mycosphere 7: 1192-1260
2012 - 119 Colletotrichum species in 9 species complexes
2016 - 190 Colletotrichum species in 11 species complexes
Phylogenetic tree based on combination of 4 fungal genes
Taxonomy of Colletotrichum2016
Redefined taxonomy of chili anthracnose De Silva et al.2016, Diao et al. 2016, Liu et al. 2016
• C. aenigma• C. conoides• C. fructicola• C. viniferum• C. hymenocallidis• C. endophytica• C. gloeosporioides• C. grossum• C. queenslandicum• C. siamense• C. asianum
gloeosporioides complex
• C. fioriniae• C. simmondsii• C. cairnsense sp nov• C. scovillei• C. nymphaeae• C. acutatum• C. brisbanense
acutatum complex
• C. coccodes
Not grouped
• C. cliviae• C. liaoningense• C. brevisporum
• C. sichuanensis
truncatum complex
• C. truncatum
boninense complex
• C. karstii
spaethianum complex
• C. incanum
New cliviae complex
• Australia, 3 species were known – now 6
• SE Asia and China, 4 species were known – now 25
(12 new reports from China)
Chili anthracnose in Australia & SE Asia
UOM 26- INDO
UOM 27- INDO
UOM 25- INDO
UOM 15- INDO
UOM 14- INDO
UOM 13- INDO
UOM 16- INDO
UOM 38- INDO
CPC30233- INDO
CPC30234- INDO
CPC30235- INDO
CPC30236- INDO
CPC30237- INDO
CPC30238- INDO
F7-4A- THAI
UOM 3- SRI
UOM 4- SRI
UOM 5- SRI
F4-1C- THAI
UOM 21- AUS
UOM 1- AUS
UOM 2- AUS
UOM 3- AUS
C_siamense_(syn_C_hymenocallidis)CBS_125378
C_siamense_(syn_C_jasmini_sambac)CBS_130420
C_siamense_CBS_130417
F1-3A- THAI
F7-3B-THAI
-F1-3CTHAI
CPC 28609- INDO
F5-4A-THAI
F5-1A-THAI
F7-1B-THAI
C_salsolae_ICMP_19051
COLL1298-TWN
COLL1290-TWN
CPC 28555-INDO
CPC 28612-INDO
CPC 28611-INDO
C_queenslandicum_ICMP_1778
UOM 20- AUS
UOM19-AUS
UOM 6-AUS
UOM 7-AUS
UOM 4- AUS
UOM 22- AUS
C_asianum_ICMP_18580
C_tropicale_ICMP_18653
CPC 28608- INDO
CPC 28607- INDO
UOM 42- INDO
UOM 43- INDO
C_aeschynomenes_ICMP_17673_ATCC_201874
F5-2D- THAI
C_musae_ICMP_19119
C_aenigma_ICMP_18608
C_nupharicola_ICMP_18658
C_fructicola_ICMP_18581
COLL1318-TWN
COLL 853-TWN
CPC 28644-INDO
CPC 28645-INDO
C_gloeosporioides_CBS_112999
C_alatae_ICMP_17919
C_xanthorrhoeae_CBS_127831
C_horii_ICMP_10492
C_henanenseLC3030_CGMCC_3_17354_LF238
C_ti_ICMP_4832
C_aotearoaICMP_18537
C._cordylinicola_ICMP_18579
C_psidii_CBS_145_29_ICMP_19120 N
C_clidemiae
C_kahawae_ICMP_17816
C_camelliaeCGMCC_3_14925_LC1364
C_theobromicola_CBS_124945
C._grevilleae_CBS_132879_CPC_15481
9993
87
88
73
99
99
54
88
94
99
60
32
99
99
100
81
99
100
99
99
99
100
80
100
42
53
100
55
99
95
9594
100
99
73
98
62
63
58
64
0.02
C. siamense
NEW
C. queenslandicum
NEW
C. fructicola
NEW
NEW
Gloeosporioides complex based on maximum likelihood analysis of ITS, TUB2, ApMat and GS genes
AUS- Australia
INDO- Indonesia
SRI- Sri Lanka
THAI-Thailand
TWN- Taiwan
Gloeosporioides complex
• C. siamense widespread throughput SE Asia and Aust
• C. siamense and C. queenslandicum associated with other hosts, as is C. fructicola
• New species in Indonesia (Sulawesi), Taiwan and Thailand (Kanchanburi)
C_scovillei_CBS:120708
C_scovillei_CBS_126529
C_guajavae_CPC_18893
C_chrysanthemi_CBS_126518
AUS_13
AUS_18
AUS_16
AUS_11
AUS_12
AUS_17
C_walleri_CBS:125472
C_cosmi_CBS:853.73
C_nymphaeae_CBS_515_78
INDO_3
C_brisbanense_CBS_292.67
C_laticiphilum_CBS:112989
C_indonesiense_CBS_127551
C_sloanei_IMI:364297
C_simmondsii_BRIP_28519
AUS_14
AUS8
AUS9
AUS10
AUS_15
C_lupini_CBS_109225
C_fioriniae_CBS:128517
C_acutatum_CBS_127539
C_acutatum_CBS_112996
C_godetiae_CBS_133_44
C_boninense_CBS_123755
100
60
100
97
80
63
86
98
94
58
58
99
99
69
91
77
88
90
94
99
75
95
0.02
T211-THAI
COLL153-- TWN
MJ8- THAI
COLL329-TWN
MJ3-THAI
COLL-524- TWN
MJ7-THAI
MJ8-THAI
316-THAI
COLL683- TWN
MJ5- THAI
COLL1300-TWN
GA1-THAI
GA3- THAI
GA2- THAI
GA5- THAI
UOM- 16- INDO
UOM- 11- INDO
UOM 12- INDO
UOM M5- MLS
UOM M4- MLS
UOM M3-MLS
UOM M1-MLS
UOM 8- INDO
313- THAI
UOM 7- INDO
UOM M6-MLS
COLL 1301- TWN
211- THAI
UOM6- INDO
314- THAI
UOM- 9- INDO
311- THAI
UOM 4- INDO
C. cairnsense
C. simmondsii
C. scovillei
C_scovillei_CBS:120708
UOM 6- INDO
UOM 5- INDO
314- THAI
UOM 1- INDO
UOM 2- INDO
UOM 3- INDO
UOM 14- INDO
UOM 13- INDO
UOM 15- INDO
C. brisbanense
GA4- THAI
COLL-883- TWN
UOM- 10- INDO
UOM- 10- INDO
99
95
Acutatum complex based on maximum likelihood analysis of ITS, TUB2, GAPDH, ACT, HIS and CHS genes
AUS- Australia
INDO- Indonesia
SRI- Sri Lanka
THAI-Thailand
MLS- Malaysia
TWN- Taiwan
Acutatum complex
• C. scovillei widespread throughout SE Asia but not in Aust.
• C. cairnsense only in Australia
• Limited diversity of acutatum complex species outside of Aust
Colletotrichum cairnsense sp. nov.
Other complexes based on maximum likelihood analysis of ITS, TUB2, GAPDH, ACT and CHS genes
C. karstii
C. cliviae
INDO- Indonesia
THAI-Thailand
boninense complex
cliviae complex
C karstii CBS:125468
C karstii CAUOS1 Chili China
C karstii CAUOS7 Chili China
C karstii CBS:127595
C karstii CBS 132134
C karstii CBS:128545
28553 -INDO
28554 -INDO
28601 -INDO
28602-INDO
C phyllanthi CBS:175.67
C annellatum CBS:129826
C petchii CBS:378.94
C boninense CBS 123755
C beeveri CBS:128527
C brassicicola CBS:101059
C brasiliense CBS 128501
C constrictum CBS:128504
C.truncatum CBS151.35
C liaoningenses CAUOS2
C brevisporum L57/LC0600
C liaoningenses CAUOS3
CA2-THAI
CA3-THAI
CA1-THAI
CPC 28639-THAI
CPC 28638- THAI
C sichuanensis LJTJ3
C sichuanensis LJTJ16
C cliviae CBS:125375
C cliviae CSSS2
C cliviae CSSS1
C tropicicola L58/LC0598
96
100
99
81
73
60
88
100
100
100
10099
100100
99
98
100
5099
90
53
89
40
48
42
0.02
Cliviae complex
• Isolates from Thailand from leaves in Chiang Rai and fruit in Bangkok
• C. sichuanensis probably misidentified and is in fact C. cliviae
a
e
c
d
b
f
b
Isolates from cliviae complex
Colletotrichum spp causing anthracnose in Thailand
Location No. isolates
Species
Chiang Mai 10 C. scovillei
KU site 4 C. scovillei
Ratchaburi 2 C. siamense
Kanchana Buri 21
C. siamenseNew species
Nakhon Pathom 3 C. siamense
Chiang Rai 32
C. scovilleiC. cliviae
Bangkok 3 C. cliviae
Species name C. bangchang C. chinensis PBC:932
RED GREEN RED GREEN
W NW W NW W NW W NW
cliviae complex C. cliviae 1 0 0 0 0 0 0 0
boninense complex C. karstii 1 1 1 1 1 0 0 0
gloeosporioidescomplex
C. fructicola 1 0 1 1 1 0 0 0
new_4 (Thailand) 1 0 0 0 1 0 0 0
C. siamense 1 1 1 1 1 0 0 0
C. queenslandicum 1 1 1 1 1 0 1 0
new_1 (Taiwan) 1 0 1 0 1 0 0 0
new_2 (Indonesia) 1 0 1 1 1 0 0 0
new_3 (Indonesia) 1 0 1 0 0 0 0 0
acutatumcomplex
C. cairnsense 1 1 1 1 1 0 1 0
C. scovillei 1 1 1 1 1 1 1 1
C. simmondsii 1 1 1 1 1 0 0 0
C. brisbanense 1 1 1 1 1 1 0 0
Pathogenicity of Colletotrichum species (ability to cause infection on wounded & non-wounded fruit)
Pathogenicity of species• Results do not consider virulence or pathotype
differences between isolates
• C. scovillei most pathogenic – infect PBC, NW
• C. cairnsense & C. queenslandicum next most pathogenic but not able to infect PBC, NW
• Species were less likely to infect non wounded fruit – cuticle resistance?
• Wounded green fruit of PBC was generally more resistant then wounded red fruit, no difference for non-wounded fruit
To Wound or not to Wound fruit in a bioassay?
• Wounding
–Mongkolporn’s group at Kasetsart Uni identified pathotypes of Colletotrichum spp on red and green fruit; and resistance genes in Capsicumspecies
• Non wounding
– At Uni of Melb, a cutinase pathogenicity gene was cloned from C. truncatum and shown to be important in establishing initial infection of chili fruit.
Pathogenicity summary
• Cuticle of the fruit plays an important role as the primary mechanism of defence against infection by Colletotrichum spp. – especially in C. annuum.
• Cellular defence may be inducible resistance but only identified in Capsicum species – C. baccatum, C. chinense.
• Bioassays to screen Capsicum germplasm for resistance should be based on both wounding and non-wounding methods.
UM Plant Pathology PhD students
PhD student Dilani de Silva
Assoc Prof Orarat Mongkolporn, Kasetsart University, Thailand
Dr Marti Pottorff, AVRDC - World Vegetable Centre, Taiwan