Ecophysiological and molecular mechanisms of weed seed bank persistence

Weeds are a major threat to modern agriculture. For example, blackgrass is considered the most destructive cereal weed in European agriculture (1). Seed dormancy in agricultural weeds is the key factor regulating weed emergence patterns in the field. Together with seed viability and persistence, it affects the behaviour of the weed seed bank, which is of vital importance to designing effective weed control strategies. Blackgrass is propagated solely by seed (2). Release of the innate dormancy of this seed results in two peaks of seedling emergence during the growing season: a major peak in autumn and a minor peak in spring, affecting the establishment of winter and spring cereals respectively (3).

This phenomenon is well described in field experiments (1,4,5) that provide an agro-ecological description of blackgrass seedling emergence, however the ecophysiological and molecular mechanisms underpinning the enforcement and release of seed dormancy, viability and persistence in blackgrass and other important weeds remain largely unknown. This project aims to investigate these mechanisms for informing the development of more effective emergence models and control strategies. Having established that temperature has an important role in the dormancy release and with identified candidate genes involved in this process using an RNAseq approach (Holloway et al., 2019, in prep.), the proposed interdisciplinary project would build on this work.