Role of ‘Underdeveloped’ Embryos in Germination/ Dormancy Problems
Changes in embryo development in germinating seeds of Melianthus major (Melianthaceae)
This project is one a series in the theme of 'Ecophysiology and Morphology'.
Morphological (MD) and morpho-physiological (MPD) dormancy are an endogenous type of seed dormancy described for seeds including those with underdeveloped or undifferentiated embryos. Seeds with such embryos have been observed in > 55 plant families. Morphologically dormant species can take < 30 d to germinate, whereas morpho-physiologically dormant species will take > 30 d before radicle protrusion.
The optimal germination conditions are unknown for many collections from plant families believed to exhibit MD or MPD. Furthermore, analyses of successful MSB germination tests show that 335 collections currently held take > 56 d to germinate and therefore may be described as having MPD.
This project aims to investigate the pattern of embryo development in MSB collections thought to have MPD, during laboratory treatments that seek to overcome dormancy whilst mimicking seasonal conditions relevant to the climate of origin. One family of particular interest has been the Amaryllidaceae. Studies into the germination requirements of a couple of European amaryllids have shown that embryo growth occurs during warm summer stratification with germination following in cooler autumn temperatures.
Project Team
Project Leader: Stuppy, Wolfgang
Herbarium
Aaron Davis
Seed Conservation Department
John Adams, Fiona Hay, Rosemary Newton, Robin Probert
Funders
UK
MSBP