| Summary: | The deployment of <i>Eucalyptus pellita</i> trees that are resistant to <i>Ceratocystis manginecans</i> is essential for the commercial plantations and therefore the sustainability of forest industries in Southeast Asia that utilize this resource. Current screening procedures are time-consuming and expensive but could be expedited with the aid of marker-assisted selection and breeding. The identification of genotypes with resistance to the disease may be facilitated if microsatellite markers developed in other <i>Eucalyptus</i> species are transferable and can be linked to quantitative trait loci (QTL) for disease resistance. This possibility was tested in 111 full-sib progenies and their parents by genotyping with 49 microsatellite markers developed in other <i>Eucalyptus</i> species. Disease development was assessed after stem inoculation with <i>C. manginecans</i> isolate Am60C. The disease index (DI) varied from 0 to 20% of stem length. There was a continuous distribution of resistant and susceptible seedlings with 60% in the resistant category. Of the 30 acceptable markers, 17 (56%) defined two linkage groups (LG). In each LG, one QTL with a significant logarithm of odds (LODs > 13) was identified. The transferability of microsatellite markers developed in other <i>Eucalyptus</i> species facilitated the rapid identification of LGs and QTLs in <i>E. pellita</i>. To further refine the linkage map, the testing of more microsatellite markers and a larger population of progenies are required.
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