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Dormancy-breaking and seed germination studies in genus Lilium reveal that the majority of Lilium spp. studied have an underdeveloped embryo at maturity, which grows inside the seed before the radicle emerges. Additionally, the embryo, radicle or cotyledon has a physiological component of dormancy; thus, Lilium seeds have morphophysiological dormancy (MPD). A previous study suggested that seeds of Lilium polyphyllum have MPD but the study did not investigate the development of the embryo, which is one of the main criteria to determine MPD in seeds. To test this hypothesis, we investigated embryo growth and emergence of radicles and epicotyls in seeds over a range of temperatures. At maturity, seeds had underdeveloped embryos which developed fully at warm temperature within 6 weeks. Immediately after embryo growth, radicles also emerged at warm temperatures. However, epicotyls failed to emerge soon after radicle emergence. Epicotyls emerged from >90% seeds with an emerged radicle only after they were subjected to 2 weeks of cold moist stratification. The overall temperature requirements for dormancy-breaking and seed germination indicate a non-deep simple epicotyl MPD in L. polyphyllum.

Angelica glauca (Apiaceae), endemic to the Himalaya, is an endangered medicinal herb for which, beside in situ conservation, ex situ cultivation is recommended to overcome poor seed germination that limits natural reproduction in the species. To determine the germination potential of the species, the germination of seeds collected from several populations were measured. Germination in seeds treated with KNO3 and NaHClO3 before sowing was significantly enhanced as compared with untreated controls and reduced the mean germination time under laboratory and nursery conditions. [ABSTRACT FROM AUTHOR]