Optimization of a High Throughput, Cost Effective, and All-stage DNA Extraction Protocol for Sorghum (Sorghum bicolor)

The extraction of DNA for molecular analyses is often a limiting factor in terms of cost, time, and availability of skilled labor. Here the authors describe a simple extraction protocol for obtaining DNA from field and greenhouse grown plants. This method was optimized for sampling mature wild sorghum populations in remote areas of Ethiopia and young greenhouse grown seedlings for genetic studies using microsatellite loci. Initially, the leaf squashes are made on Whatman FTA plant saver cards or small cards of Whatman® chromatography paper. After several washes, sufficient DNA to run up to 70 PCR amplifications is eluted from a 6 mm disk. Both types of cards were equally effective for collecting genomic DNA from young and mature sorghum plants for PCR-based analyses. The use of this technology for extracting genomic DNA from seedlings and/or mature plants in situ is particularly attractive for sampling at sites that are far from the laboratory where samples are ultimately analyzed. Moreover, highly skilled personnel are not required to collect DNA samples using this protocol. The Whatman FTA card is more expensive than the Whatman® chromatography paper. Therefore, without compromising efficiency, the lower cost chromatography paper can be used for DNA extraction, especially for institutions in developing countries.