Abstract: Plantago virginica is one of the widespread invasive weeds in southern China. The seed germination in different postharvest months, water absorption of seed mucilage and the germination of the seeds with or without mucilage under different osmosis were studied in laboratory to assess its seed dormancy and germination properties, and the effects of the mucilage in seed germination under drought environment. The seeds of P. virginica had a dormancy period about one month and kept high germination rates 2 to 9 months after mature (48.75%-88.75%). The water absorption ability of the seeds with mucilage was obviously higher than that of the seeds without mucilage, and the water absorbed by the mucilage was 59 times or so as its dry mass. Compared with the control, the germination rates of the seeds with mucilage and without mucilage decreased by 18.58% and 62.71% respectively under the osmosis stress from -1.21 to 0 MPa. Our experimental findings suggested that the characteristics of P. virginica such as short dormancy period and high germination rate of the seeds, and the obviously strong water absorption ability of seed mucilage, might contribute to its adaptation to the drought environment and indirectly enhance its invasive capability.

Key words: proline., cell membrane permeability, toxin, Alternaria alternate, chrysanthemum