Table 2.1 Summary of properties of fungal accessory chromosomes
Species
Number of
accessory
chromosomes
Size range of accessory
chromosomes (Mb)
Genes on accessory
chromosomes
influencing
pathogenicity
Phenotype when
present
Mitotic
transmission
Meiotic
transmission
References
Alternaria
alternata
1
< 2
Tox genes
Host-specific
pathogenicity
Nd (spontaneous
loss observed in
apple
pathotype)
Na
(Akagi et al. 2009b; Akamatsu et al. 1997;
Akamatsu et al. 1999; Hatta et al. 2002;
Hu et al. 2012; Johnson et al. 2001, 2001;
Kohmoto 1993; Nakashima et al. 1985;
Nakatsuka et al. 1986; Salamiah et al. 2001b;
Salamiah et al. 2001a)
Botrytis cinerea
3
0.22–0.58
None identified
None identified
Nd
Non-Mendelian (Kan et al. 1993; Van Kan et al. 2017)
Cochliobolus
carbonum
2
0.75–3.5
TOX2
High virulence
on certain
genotypes of
maize
Nd
Mendelian
(Ahn and Walton 1996;
Condon et al. 2013)
Cochliobolus
heterostrophus
1
0.75–1.2
None identified
None identified
Nd
Non-Mendelian (Condon et al. 2013; Tzeng et al. 1992)
Colletotrichum
gloeosporioides
2
1.2–2
None identified
None identified
Nd
Na
(Masel et al. 1993; Masel 1996)
Fusarium
oxysporum f.
sp. lycopersici
4
< 3.5
Secreted in xylem
(Six) genes
Pathogenicity on
tomato
Loss in 1 of 35,000
spores
Na
(Ma et al.
2010; Rep et al. 2004;
Vlaardingerbroek et al. 2016a)
Gibberella
fujikuroi MP A
1
0.7
None identified
None identified
Nd
Non-Mendelian (Xu 1995; Xu and Leslie 1996)
Leptosphaeria
maculans
2
0.7–0.95
AvrLm11,Five
effector
candidates
Avirulence on
hosts
containing
Rlm11
Nd
Non-Mendelian (Balesdent et al. 2013; Rouxel et al. 2011;
Rouxel and Balesdent 2017)
Magnaporthe
oryzae
2
0.5–2
AVR-Pita
Unknown
Nd
Non-Mendelian (Chuma et al. 2003; Chuma et al. 2011;
Orbach et al. 1996; Yoshida et al. 2009)
Nectria
haematococca
MP VI
3
0.53–1.6
Pea pathogenicity
(PEP) cluster
Pathogenicity
on pea
Nd
Non-Mendelian (Coleman et al. 2009; Miao et al. 1991)
Zymoseptoria
tritici
8
0.409–0.773
None identified
Decreased
virulence
Loss at high
frequency (up
to 1 in 2 spores)
Non-Mendelian (Croll et al. 2013; Goodwin et al. 2011;
Habig et al. 2017; Mo ¨ller
et al. 2018;
Wittenberg et al. 2009)
a
Abbreviations: nd not determined, na not applicable, MP mating population
28
M. Habig and E. H. Stukenbrock
Species
Number of
accessory
chromosomes
Size range of accessory
chromosomes (Mb)
Genes on accessory
chromosomes
influencing
pathogenicity
Phenotype when
present
Mitotic
transmission
Meiotic
transmission
References
Alternaria
alternata
1
< 2
Tox genes
Host-specific
pathogenicity
Nd (spontaneous
loss observed in
apple
pathotype)
Na
(Akagi et al. 2009b; Akamatsu et al. 1997;
Akamatsu et al. 1999; Hatta et al. 2002;
Hu et al. 2012; Johnson et al. 2001, 2001;
Kohmoto 1993; Nakashima et al. 1985;
Nakatsuka et al. 1986; Salamiah et al. 2001b;
Salamiah et al. 2001a)
Botrytis cinerea
3
0.22–0.58
None identified
None identified
Nd
Non-Mendelian (Kan et al. 1993; Van Kan et al. 2017)
Cochliobolus
carbonum
2
0.75–3.5
TOX2
High virulence
on certain
genotypes of
maize
Nd
Mendelian
(Ahn and Walton 1996;
Condon et al. 2013)
Cochliobolus
heterostrophus
1
0.75–1.2
None identified
None identified
Nd
Non-Mendelian (Condon et al. 2013; Tzeng et al. 1992)
Colletotrichum
gloeosporioides
2
1.2–2
None identified
None identified
Nd
Na
(Masel et al. 1993; Masel 1996)
Fusarium
oxysporum f.
sp. lycopersici
4
< 3.5
Secreted in xylem
(Six) genes
Pathogenicity on
tomato
Loss in 1 of 35,000
spores
Na
(Ma et al.
2010; Rep et al. 2004;
Vlaardingerbroek et al. 2016a)
Gibberella
fujikuroi MP A
1
0.7
None identified
None identified
Nd
Non-Mendelian (Xu 1995; Xu and Leslie 1996)
Leptosphaeria
maculans
2
0.7–0.95
AvrLm11,Five
effector
candidates
Avirulence on
hosts
containing
Rlm11
Nd
Non-Mendelian (Balesdent et al. 2013; Rouxel et al. 2011;
Rouxel and Balesdent 2017)
Magnaporthe
oryzae
2
0.5–2
AVR-Pita
Unknown
Nd
Non-Mendelian (Chuma et al. 2003; Chuma et al. 2011;
Orbach et al. 1996; Yoshida et al. 2009)
Nectria
haematococca
MP VI
3
0.53–1.6
Pea pathogenicity
(PEP) cluster
Pathogenicity
on pea
Nd
Non-Mendelian (Coleman et al. 2009; Miao et al. 1991)
Zymoseptoria
tritici
8
0.409–0.773
None identified
Decreased
virulence
Loss at high
frequency (up
to 1 in 2 spores)
Non-Mendelian (Croll et al. 2013; Goodwin et al. 2011;
Habig et al. 2017; Mo ¨ller
et al. 2018;
Wittenberg et al. 2009)
a
Abbreviations: nd not determined, na not applicable, MP mating population
28
M. Habig and E. H. Stukenbrock