The extraction of DNA is often the most time consuming and laborious step in high-throughput molecular genetic analysis and marker assisted selection （MAS） programs. A simple method for preparation of rice genomic DNA was developed. A small amount （1~50 mg） of leaf tissue of rice seedling, 500 pL of extraction buffer, and one steel bead were put into a 2-mL microcentrifuge tube. After vigorously mashing for 2 min, 5 μL of supernatant was directly applied to PCR amplification. Otherwise, the supematant was precipitated with two times volume of ethanol to obtain high quality genomic DNA. This method is simple, rapid, low cost, and reliable for PCR analysis. One person can manipulate as many as 96 samples for PCR in 10 min. It is especially suitable for genotyping of large number of samples.
