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We are interested in seed dormancy, seed longevity and germination and study these traits using variation that occurs in nature by means of accessions of Arabidopsis thaliana. We have identified loci/genes that control these important traits in nature, and aim for the unravelling of the molecular mechanisms. Within all research projects we have student projects are available that combine genetics, molecular biology and plant physiology. More background information and information concerning the research projects can be found below.
Figure 1: The life cyle of a flowering plant.
Introduction on seed dormancy and germination
Seeds and proper control of seed germination are very important since seeds are the link between two successive generations of plants. Seeds allow the plant to survive periods in which conditions are not optimal to complete its life cycle and allow it to be transported to new locations as well. The timing of germination is of extreme importance, when a seeds germinates at moments or under conditions that the plant cannot complete its life cycle it will die. This timing of germination is controlled by seed dormancy.
Figure 2. A) QTL map. The five chromosomes with on the right the QTL positions indicated by the green bars. QTL are named, DOG (Delay of Germination) B) Near Isogenic Lines, (NILs) with introgression fragments of different accessions at the position of the QTL. Dormancy phenotypes are indicated by the DSDS50 (days of seed dry storage required to reach 50% of germination).
Seed dormancy is an important adaptive trait that together with flowering time is a primary component of the different life history strategies of plants. Dormancy can be considered as a mechanism where growth and development is arrested, despite the presence of favourable environmental conditions for growth and development. The depth of dormancy is strongly affected by the genetic backgrounds as well environmental conditions. These environmental factors can act during seed development on the mother plant, during seed storage (after-ripening) and in imbibed (wet) mature seeds. We are interested to identify genes and pathways that control seed dormancy in nature. Therefore we have performed quantitative trait loci (QTL) analyses in six recombinant inbred line populations of Arabidopsis thaliana. Eleven QTL (delay of germination; DOG) have been identified and the effect of these loci on seed dormancy has been validated be means of near isogenic lines (NILs). These NILs have been used to identify the genes underlying the QTL and to identify downstream genes. This has been done using fine-mapping and transcriptomics analyses. The first of these QTL, DOG1 (Bentsink et al., PNAS 2006).
Projects:
The virtual seed (ERA-PG vSEED) (2009-2012)
o Bas Dekkers
o Marieke van Bolderen-Veldkamp
Seed dormancy and seed longevity, towards the identification of markers and genes (STW 2009-2013)
o Phuong Nguyen
o Leónie Bentsink
Production environment and seed quality (STW 2011-2015)
o Hanzi He
o Kerstin Gühl
Molecular and phenotypical characterization of genes that are involved in the control of seed dormancy and after-ripening (2011-2015)
o Farzaneh Yazdanpanah
The role of seed stored mRNAs and translation in the control of seed dormancy (NWO 2012-2015)
o Bing Bai |