Plant molecular breeding relies on SNP markers to select for traits without phenotyping. The bottleneck has always been extraction: getting clean, PCR-compatible DNA from hundreds or thousands of plant samples per day, from leaves, roots, or seeds, without the yield variation that defeats genotyping assays.

Application Note 017, a collaboration between Deutsche Saatveredelung AG, a German plant breeding company) and Exymes, combined phytoGEM chemistry with the LGC Hydrocycler platform to achieve exactly this. The Hydrocycler can process 960 samples per run on 96-well plates, or 6,144 samples on 384-well plates.

1. Sample types tested: dried rapeseed leaves, roots, and seeds; each presenting different cell wall densities and inhibitor profiles.

2. Extraction used phytoGEM chemistry: Histosolv at 52°C to degrade the plant cell wall, followed by prepGEM proteinase at 75°C, with 95°C heat inactivation. Total run in the Hydrocycler: 20 minutes.

3. DNA yield: seeds produced the highest concentration (mean 19.1 ng/µl), followed by dried leaves and roots. All sample types produced amplifiable DNA with a linear correlation between starting material and yield.

4. Downstream validation: undiluted and 1:5 diluted extracts were used directly in KASP SNP genotyping assays. The 1:5 dilution gave clear homozygous and heterozygous discrimination across all three sample types.

Authors: Radtke S. et al., Deutsche Saatveredelung AG / Branca C. et al., Exymes.