Editorial: Seed Science and Technology. Volume 49 Issue 1 (2021)

At the time of writing, in the UK and Northwest Europe the wood anemone (Anemone nemorosa L., Ranunculaceae) is in full flower, as Spring gets under way. This common herbaceous perennial of woodland and hedgerows is a possibly somewhat extreme example of the challenges facing conservationists striving to preserve seeds of their native species, in all their diversity, ex situ in conventional seed banks. Its seeds will survive drying, but only after the achenes, still green when shed, are dispersed from the parent plant. Ali et al. (2007) observed an initial increase in desiccation tolerance, followed by a decline; and the proportion of seeds surviving desiccation and their increase in subsequent longevity coincided with the growth and development of their embryos ex planta. However, developmental arrest of the embryo was not required for the acquisition of desiccation tolerance, and continued growth and development of the embryo resulted in loss of desiccation tolerance, analogous to that seen in orthodox (sensu Roberts, 1973) seeds upon radicle emergence. Consequently, the window of desiccation tolerance and maximum potential longevity is comparatively short; and in nature occurs when seeds are on or close to the soil surface. Though the seeds can be air-dried with care and stored at sub-zero temperatures, high initial viabilities are difficult to achieve and their storage lives are short (ten years or less under conventional seed bank conditions); throwing doubt on the role of conventional seed banking as a means of long, or even medium-term ex situ conservation for this species. Furthermore, while A. nemorosa seeds, like those of many species from the Ranunculaceae, might be described as having morphological or morphophysiological dormancy (Baskin and Baskin, 2014), the observed lack of developmental arrest is somewhat at odds with most definitions of dormancy.