Genomic DNA of rice samples was isolated and analyzed by HAT-RAPD (high annealing temperature-random amplified polymorphic DNA)[17].More than 30 arbitrary RAPD primers (QIAGENOPERON,USA) were used in PCR (polymerasechainreac-tion) amplification.The HAT-RAPD technique used an increased annealing temperature in PCR up to 46 C, resulting in greater polymorphism , reproducibility and high resolution.Reaction tubes were placed in the Perkin–Elemer thermal cycle (Gene Amp PCR system 2400) and the following cycling profile was used: 95 C for 2 min, then 95 C for 30 s for denaturation, 46–48 C for 30 s for annealing, 72 C for 45 s for extension, totally 35 cycles, andfinally, 72 C for 5 min. After the thermal cycling program was completed, the amplified samples were stored at 4 C for electrophoresis