| Panicum macrostachyum (Kunth) Nees, 1829 |
| Panicum macrostachyum var. patens Döll, 1877 |
| Panicum macrourum Trin., 1834 |
| Panicum maculatum Reichb. ex Schldl. & Cham., 1831 |
| Panicum maculatum var. pilosum E. Fourn., 1886 |
| Panicum malabaricum (L.) Merr., 1909 |
| Panicum malacon Nash, 1897 |
| Panicum malacophyllum (Trin.) Kuntze, 1898 |
| Panicum malacophyllum var. cordovense Kuntze, 1898 |
| Panicum malacophyllum var. elongatum (Griseb.) Kuntze, 1898 |
| Panicum manatense Nash, 1897 |
| Panicum marginellum Schrad., 1838 |
| Panicum martianum Nees, 1829 |
| Panicum martinicense Griseb., 1864 |
| Panicum maximum Jacq., 1781 |
| Panicum maximum var. bulbosum (Kunth) Vasey, 1878 |
| Panicum maximum var. gongylodes (Jacq.) Döll, 1877 |
| Panicum maximum var. maximum Jacq., 1781 |
| Panicum maximum var. trichoglume Robyns, 1932 |
| Panicum maynense Trin., 1836 |