Farming termites determine the genetic population structure of Termitomyces fungal symbionts

TY - JOUR

T1 - Farming termites determine the genetic population structure of Termitomyces fungal symbionts

AU - Nobre, Tânia

AU - Fernandes, Cecília

AU - Boomsma, Jacobus J

AU - Korb, Judith

AU - Aanen, Duur K

N1 - © 2011 Blackwell Publishing Ltd.

PY - 2011/5

Y1 - 2011/5

N2 - Symbiotic interactions between macrotermitine termites and their fungal symbionts have a moderate degree of specificity. Consistent with horizontal symbiont transmission, host switching has been frequent over evolutionary time so that single termite species can often be associated with several fungal symbionts. However, even in the few termite lineages that secondarily adopted vertical symbiont transmission, the fungal symbionts are not monophyletic. We addressed this paradox by studying differential transmission of fungal symbionts by alate male and female reproductives, and the genetic population structure of Termitomyces fungus gardens across 74 colonies of Macrotermes bellicosus in four west and central African countries. We confirm earlier, more limited, studies showing that the Termitomyces symbionts of M. bellicosus are normally transmitted vertically and clonally by dispersing males. We also document that the symbionts associated with this termite species belong to three main lineages that do not constitute a monophyletic group. The most common lineage occurs over the entire geographical region that we studied, including west, central and southern Africa, where it is also associated with the alternative termite hosts Macrotermes subhyalinus and Macrotermes natalensis. While Termitomyces associated with these alternative hosts are horizontally transmitted and recombine freely, the genetic population structure of the same Termitomyces associated with M. bellicosus is consistent with predominantly clonal reproduction and only occasional recombination. This implies that the genetic population structure of Termitomyces is controlled by the termite host and not by the Termitomyces symbiont.

AB - Symbiotic interactions between macrotermitine termites and their fungal symbionts have a moderate degree of specificity. Consistent with horizontal symbiont transmission, host switching has been frequent over evolutionary time so that single termite species can often be associated with several fungal symbionts. However, even in the few termite lineages that secondarily adopted vertical symbiont transmission, the fungal symbionts are not monophyletic. We addressed this paradox by studying differential transmission of fungal symbionts by alate male and female reproductives, and the genetic population structure of Termitomyces fungus gardens across 74 colonies of Macrotermes bellicosus in four west and central African countries. We confirm earlier, more limited, studies showing that the Termitomyces symbionts of M. bellicosus are normally transmitted vertically and clonally by dispersing males. We also document that the symbionts associated with this termite species belong to three main lineages that do not constitute a monophyletic group. The most common lineage occurs over the entire geographical region that we studied, including west, central and southern Africa, where it is also associated with the alternative termite hosts Macrotermes subhyalinus and Macrotermes natalensis. While Termitomyces associated with these alternative hosts are horizontally transmitted and recombine freely, the genetic population structure of the same Termitomyces associated with M. bellicosus is consistent with predominantly clonal reproduction and only occasional recombination. This implies that the genetic population structure of Termitomyces is controlled by the termite host and not by the Termitomyces symbiont.

KW - Africa, Central

KW - Africa, Southern

KW - Animals

KW - Biological Evolution

KW - DNA, Fungal

KW - Female

KW - Isoptera

KW - Male

KW - Phylogeny

KW - Recombination, Genetic

KW - Sequence Analysis, DNA

KW - Symbiosis

KW - Termitomyces

U2 - 10.1111/j.1365-294x.2011.05064.x

DO - 10.1111/j.1365-294x.2011.05064.x

M3 - Journal article

C2 - 21410808

SN - 0962-1083

VL - 20

SP - 2023

EP - 2033

JO - Molecular Ecology

JF - Molecular Ecology

IS - 9

ER -