Fourie, AristaVan der Nest, Magrieta AlettaDe Vos, LieschenWingfield, Michael J.Wingfield, Brenda D.Barnes, Irene2020-02-042019-10Fourie, A., Van der Nest, M.A., De Vos, L. et al. 2019, 'QTL mapping of mycelial growth and aggressiveness to distinct hosts in Ceratocystis pathogens', Fungal Genetics and Biology, vol. 131, art. 103242, pp. 1-15.1087-1845 (print)1096-0937 (online)10.1016/j.fgb.2019.103242http://hdl.handle.net/2263/73079Some species of Ceratocystis display strong host specificity, such as C. fimbriata sensu stricto that is restricted to sweet potato (Ipomoea batatas) as host. In contrast, the closely related C. manginecans, infects Acacia mangium and Mangifera indica but is not pathogenic to I. batatas. Despite the economic importance of these fungi, knowledge regarding the genetic factors that influence their pathogenicity and host specificity is limited. A recent inheritance study, based on an interspecific cross between C. fimbriata and C. manginecans and the resultant 70 F1 progeny, confirmed that traits such as mycelial growth rate, spore production and aggressiveness on A. mangium and I. batatas are regulated by multiple genes. In the present study, a quantitative trait locus (QTL) analysis was performed to determine the genomic loci associated with these traits. All 70 progeny isolates were genotyped with SNP markers and a linkage map was constructed. The map contained 467 SNPs, distributed across nine linkage groups, with a total length of 1203 cm. Using the progeny genotypes and phenotypes, one QTL was identified on the linkage map for mycelial growth rate, one for aggressiveness to A. mangium and two for aggressiveness to I. batatas (P < 0.05). Two candidate genes, likely associated with mycelial growth rate, were identified in the QTL region. The three QTLs associated with aggressiveness to different hosts contained candidate genes involved in protein processing, detoxification and regions with effector genes and high transposable element density. The results provide a foundation for studies considering the function of genes regulating various quantitative traits in Ceratocystis.en© 2019 Elsevier Inc. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Fungal Genetics and Biology. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. A definitive version was subsequently published in Fungal Genetics and Biology, vol. 131, art. 103242, pp. 1-15, 2019. doi : 10.1016/j.fgb.2019.103242.Quantitative trait locus (QTL)Host specificityReciprocal translocationSordariomycetesIon TorrentSNP markersCeratocystis pathogensPostprint Article