Dormant seeds in the soil detect and respond to seasonal changes in soil temperature by changing their sensitivity to plant hormones, new research by the University of Warwick has found.
This sensitivity alters the depth of dormancy, indicating to the seed when it is the right time of year to germinate and grow.
The seeds of common weeds can survive in the soil in a dormant state for years, in some cases decades, spelling issues for food security when they emerge to compete with crops.
New DEFRA-funded research by the University of Warwick sheds light on how hormones regulate the dormancy cycle of seeds in the soil using seeds of Arabidopsis - commonly known as Thale Cress - a close relative of many common weeds and crop species.
The new insights, which come from combining modern molecular biology with traditional seed ecology, could be of long-term help in reducing the use of herbicide on farms.
It is also of interest to those working to ensure biodiversity by understanding how dormancy and germination in wild plants is regulated.
Despite the importance of dormancy cycling in nature, very little is known about its regulation at the molecular level.
Professor Bill Finch-Savage and Dr Steve Footitt in the University of Warwick's School of Life Sciences looked at gene expression over the dormancy cycle of Arabidopsis seeds in field soils to see how it is affected by the seasons.
They found that gene sets related to dormancy and germination are highly sensitive to seasonal changes in soil temperature.
A balance between the hormones abscisic acid (ABA) and gibberellic acid (GA) is thought to be central to controlling dormancy and germination,
One set of genes is regulated by ABA, which is linked to dormancy, whereas GA controls genes which act to increase the potential for germination.
Using an Arabidopsis strain whose seedlings emerge in late summer and earl
|Contact: Anna Blackaby|
University of Warwick