Abstract: The allelopathic effect of the aqueous extraction of Polytrichum commune Hedw. and Conocephalum japonicum(Thunb.) Grolle.on the seed gerimination and seedling growth was determined. The seeds of Vigna radiate, Raphanus sativus and Brassica campestris were used as bioassay materials, and the indices including the germinating rate, germinating index, germination energy, seed vitality, weight of seedling and radicle, as well as root length were determined. The experiments show that Vigna radiate is an ideal bioassay material, and the seed vitality index, seedling root weight, and root length are perfect bioassay indices for the two bryophytes. Besides, the effects of the aqueous extractions of the two bryophytes on the seed germination and seedling growth are somewhat similar to those of phytohormones, the aqueous extraction at low concentration is able to promote the seed germination and seedling growth, while inhibit at higher concentration.

Key words: Polytrichum commune Hedw., Conocephalum japonicum(Thunb.) Grolle., bioassay, allelopathy effect