RESUMEN
Next-generation sequencing requires intact and high-quality DNA. However, typical liquid-nitrogen DNA extraction methods are expensive and not practical for field sample collections. Hence, we present a cost-effective method for DNA extraction from silica-dried leaf samples, eliminating the need for liquid nitrogen. Two protocols were evaluated to determine the effectiveness of grinding dried plant samples without liquid nitrogen in comparison to the standard protocol for tissue homogenization and cell lysis. Protocol 1 involved grinding fresh leaf samples with liquid nitrogen, while Protocol 2 entailed incubating dried plant samples at-20 °C for 1 h before grinding in the absence of liquid nitrogen. Both protocols produced comparable DNA yields with an average A260/A280 ratio of 1.78±0.02, suitable for short- and long-read sequencing. Using Protocol 2, we successfully assembled ten plastomes. It also demonstrated versatility as comparable DNA quality was obtained from dried mollusks and actinomycetes, resulting in the successful assembly of two complete mitochondrial genomes. The protocol is advantageous for research workflows involving the collection of samples in the field as a long-term source of genetic material.â¢Drying: Fresh samples were silica-dried at silica-to-sample ratio of 2:1.â¢Pre-lysis: Dried samples were frozen at -20 °C for 1 hour before grinding.â¢Frozen samples were subjected to tissue homogenization followed by the standard CTAB DNA extraction.
RESUMEN
Senna alata, a flowering shrub, is widely cultivated in the Philippines for its anti-fungal properties. Despite this, its chloroplast genome is not yet established. We assembled and annotated the complete chloroplast genome of accession from the germplasm collection of the Institute of Crop Science, University of the Philippines, Los Baños, using Illumina sequencing data. The complete cp genome was 159,176-bp long characterized by a large single copy of 88,769 bp, short single-copy of 18,301 bp and a pair of inverted repeat regions of 26,053 bp each. The overall GC content of the chloroplast genome was 36.4%. The plastome comprised 37 tRNA genes, 8 rRNA genes and 78 mRNA genes. Phylogenetic analysis showed that S. alata is closely related to S. siamea.
RESUMEN
The three-leaved chaste tree (Vitex trifolia) is a medicinal and ornamental plant widely distributed from East Africa to the Pacific but has no complete chloroplast genome sequence. We assembled and characterized the V. trifolia accession from the germplasm collection of the Institute of Crop Science, University of the Philippines Los Baños. The complete plastome sequence is 154,444-bp long with 131 coding genes comprising 87 mRNA genes, 36 tRNA genes, and 8 rRNA genes. A phylogenetic analysis of the assembled genome, together with nine other Lamiaceae species, identified V. rotundifolia as its closest relative with available complete cpDNA sequence. The clustering also supports the genotypic similarity of the species belonging to trifolia group of the genus Vitex.