Influence of environmental factors on seed germination and seedling emergence of Oriental mustard (Sisymbrium orientale)

The effects of environmental factors on seed germination and seedling emergence of Oriental mustard were studied in laboratory and field experiments. Seed germination was stimulated by light; however, some germination occurred in the dark. In light/dark, potassium nitrate at 0.02 M stimulated germination of 1-mo-old seed to a maximum level of 45% as compared with the control (18%). Oriental mustard germination was inhibited by high levels of salt and osmotic stress. Seed germination was greater than 50% over a pH range of 4 to 10. Seedling emergence of 4- to 5-mo-old seeds was highest when present on the soil surface (70%) but declined with depth, and no seedlings emerged from a soil depth of 10 mm. In the field, seedling emergence was greater under no-till than minimum tillage systems.