Development and Application of Specific Molecular Markers for the Authenticity Identification in Hybrid Pennisetum

In order to develop a rapid and accurate identification method for the authenticity of hybrid Pennisetum, the molecular markers were developed based on the specific sequences derived from the genomes of pearl millet (Pennisetum glaucum) and elephant grass (Pennisetum purpureum) for the authenticity identification of hybrid Pennisetum, with validation conducted via chromosome counting and genomic in situ hybridization (GISH) on 16 candidate progeny lines. The results showed that 1146, 2421, and 4067 specific sequences were screened out by the comparative sequence analysis of A subgenome of pearl millet, along with the A' and B subgenomes of elephant grass. A total of 21 molecular markers were developed from these three subgenomes, and three highly efficient markers were ultimately screened. The results of PCR amplification and agarose gel electrophoresis revealed that 13 out of the 16 candidate lines were true allotriploid hybrid Pennisetum, while the lines Minmu No. 6, Reyan No. 4, and Guimu No. 1 were identified as tetraploid elephant grass rather than genuine hybrids. The results of chromosome counting and GISH were fully consistent with the molecular markers, which confirmed the reliability of the marker system. This method successfully established the authenticity identification technology of hybrid Pennisetum, and provided a reference for the identification of hybrids in other complex polyploid plant species.