THE GERMINATION OF SOME WOODLAND HERBACEOUS SPECIES UNDER LABORATORY CONDITIONS: A MULTIFACTORIAL STUDY

Abstract

S ummary The effects of five potentially dormancy‐breaking treatments – potassium nitrate, scarification, ethylene, light, and scarification ‐ were tested on 13 species from deciduous woodland, in a complete factorial experiment. The seeds were about 6‐months‐old and were germinated at 18°. None of the treatments induced germination in Mercurialis perennis or Sanicula europaea. Milium effusum and Silene dioica germinated well over a very wide range of conditions. Stratification promoted the germination of Endymion non‐scriptus, Galium aparine and Veronica hederifolia ; while scarification mostly had a depressive effect, except in the cases of E. non‐scriptus and Geranium robertianum where some promotion of germination was discovered. Circaea lutetiam and Veronica montana appeared to have highly specific germination requirements: the former species required nitrate, ethylene, and light in combination; while the latter required nitrate, light and stratification in combination for germination. Geum urbanum germinated well if treated with nitrate alone, while Veronica chamaedrys required light only, and Stachys sylvatica gave good germination with stratification alone. There were also several significant first‐ and second‐order interactions. Where possible, the results are discussed in relation to previous work and to the ecology of the species.