Abstract:

Orthogonal design was applied to optimize SRAP-PCR system of Guava (Psidium guajava L.). Five main factors influencing on SRAP-PCR, including Mg2+, dNTPs, primer, Taq DNA polymerase and DNA template were examined by using orthogonal design. The results showed that the optimum concentration was Mg2+ 2.5 mmol/L, dNTPs 0.15 mmol/L, primer 0.4 μmol/L, Taq DNA polymerase 1.5 U, 20 ng template DNA with a total volume of 20 μL reaction solution, which suitable for P. guajava SRAP-PCR amplification. The molecular identification of 5 varieties of P. guajava was conducted by 64 SRAP primer combinations with the optimal SRAP marker system. It showed that the SRAP primers and its optimized system could be applied in the germplasm identification and genetic diversity analysis of P. guajava effectively.