Long-fragment targeted capture for long read sequencing of plastomes
Third generation sequencing methods generate significantly longer reads than those produced using alternative sequencing methods. This provides increased possibilities to better study biodiversity, phylogeography and population genetics. We developed a protocol for in-solution enrichment hybridization capture of long DNA fragments applicable to complete chloroplast genomes. The protocol uses cost effective in-house probes developed via long-range PCR and was used in six non-model monocot species (Poaceae: African rice, pearl millet, fonio; and three palm species). DNA was extracted from fresh and silicagel dried leaves. Our protocol successfully captured long read chloroplast fragments (up to 4264 bp median) with an enrichment rate ranging from 15% to 98%. DNA extracted from silicagel dried leaves led to low quality plastome assemblies when compared to freshly extracted DNA. Our protocol could also be generalized to capture long sequences from specific nuclear fragments.