The nested PCR amplified products were analyzed for sequence polymorphism on 40%–60% linear DNA denaturing gradient polyacrylamide gel, 0.8 g·L−1 alongside species-specific markers using DCode system (Bio-Rad, Hercules, CA, USA) for 16 h at 58 °C and 60 V in 1× Tris-acetate-EDTA buffer, pH 8.5.19 (link),30 (link) The gels were stained with ethidium bromide solution (0.5 µg·mL−1) for 15 min and the images digitally captured using Alpha Imager 3300 system (Alpha Innotech San Leandro, CA, USA).