Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica.

TY - JOUR

T1 - Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica.

AU - Van Putten, W.F.

AU - Biere, A.

AU - Van Damme, J.M.M.

N1 - Reporting year: 2003 Metis note: 3178; CTE; PVP ; TE file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2003/VanPutten_ea_3178.pdf

PY - 2003

Y1 - 2003

N2 - We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically, we investigated whether strains from allopatric host populations have higher competitive ability on their native host species and show positive assortative mating. In general, strains isolated from S. latifolia outcompeted strains isolated from S. dioica on both host species, but in female hosts, heterotypic dikaryons (i.e., dikaryons composed of a haploid strain originating from S. latifolia and a haploid strain originating from S. dioica) were most successful in competition. Furthermore, the latency period was significantly shorter for heterokaryons that contained at least one strain originating from S. latifolia, compared to heterokaryons that only contained strains originating from S. dioica. The frequencies of conjugations between strains originating from S. latifolia were much higher than conjugation frequencies between strains originating from S. dioica. A significant positive correlation was detected between the relative success of strains in competition and in conjugation, suggesting that success of a strain in competition might be partly determined by its swiftness of mating. In addition, reciprocal differences within heterotypic crosses revealed a significant effect of fungal mating type, with mating type a1 being the main determinant of mating pace. The observed differences in infection success, conjugation rate, and latency period in favor of strains from S. latifolia relative to strains from S. dioica on both host species are discussed in an evolutionary context of opportunities for the maintenance of differentiation between different formae speciales upon secondary contact [KEYWORDS: Competition success, conjugation, formae speciales, mating success, mating type, smut fungus]

AB - We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically, we investigated whether strains from allopatric host populations have higher competitive ability on their native host species and show positive assortative mating. In general, strains isolated from S. latifolia outcompeted strains isolated from S. dioica on both host species, but in female hosts, heterotypic dikaryons (i.e., dikaryons composed of a haploid strain originating from S. latifolia and a haploid strain originating from S. dioica) were most successful in competition. Furthermore, the latency period was significantly shorter for heterokaryons that contained at least one strain originating from S. latifolia, compared to heterokaryons that only contained strains originating from S. dioica. The frequencies of conjugations between strains originating from S. latifolia were much higher than conjugation frequencies between strains originating from S. dioica. A significant positive correlation was detected between the relative success of strains in competition and in conjugation, suggesting that success of a strain in competition might be partly determined by its swiftness of mating. In addition, reciprocal differences within heterotypic crosses revealed a significant effect of fungal mating type, with mating type a1 being the main determinant of mating pace. The observed differences in infection success, conjugation rate, and latency period in favor of strains from S. latifolia relative to strains from S. dioica on both host species are discussed in an evolutionary context of opportunities for the maintenance of differentiation between different formae speciales upon secondary contact [KEYWORDS: Competition success, conjugation, formae speciales, mating success, mating type, smut fungus]

KW - NIOO/CTE/PVP

U2 - 10.1111/j.0014-3820.2003.tb00288.x

DO - 10.1111/j.0014-3820.2003.tb00288.x

M3 - Article

SN - 0014-3820

VL - 57

SP - 766

EP - 776

JO - Evolution

JF - Evolution

IS - 4

ER -