Gene polymorphisms in glyphosate-resistant and -susceptible biotypes of Eleusine indica from Malaysia

Resistant (R) and susceptible (S) biotypes of Eleusine indica were collected from four areas, namely Chaah, Lenggeng, Bidor and Temerloh, in Malaysia. Restriction fragment length polymorphism (RFLP) and polymerase chain reaction (PCR)-RFLP analyses using Sph I restriction enzyme were able to differentiate the R biotype from the S biotype by showing R-specific and S-specific polymorphisms in E. indica from three of the areas, with the exception of Temerloh where no polymorphisms were detected. The different DNA profiles for the R biotypes obtained indicate that Sph I is not a useful diagnostic marker. The DNA polymorphisms detected in the 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase gene suggest that there are different mutation events leading to development of resistance to glyphosate. Partial sequencing of the EPSP synthase gene confirmed different mutations occurring with substitution of proline with serine or threonine at amino acid 106 for the R biotype in Chaah, Bidor and Temerloh.