MODELLING SEED DESICCATION SENSITIVITY USING THE ARABIDOPSIS abi3-6 SEED DEVELOPMENTAL MUTANT
Marques, A.1, Nogueira, R.1, Nijveen, H.2, Kuil, A.1, Somi, C.1, Ligterink, W.1 and Hilhorst, H.1
1Laboratory of Plant Physiology, Wageningen University, Wageningen, The Netherlands
2Bioinformatics Group, Wageningen University, Wageningen, The Netherlands
Contact: Alexandre Marques, firstname.lastname@example.org
Seeds are important for plants as means of regeneration. Desiccation tolerance (DT) is an important mechanism that allows them to withstand long periods of dry storage in a quiescent state. In nature, DT is one of the main mechanisms to avoid extinction of plant species and allows their conservation ex situ. Desiccation sensitive-seeded species face imminent risk of extinction due to deforestation and climate change whereas ex situ conservation is not possible with the currently available methods.
The mechanisms causing seed desiccation sensitivity (DS) are poorly understood. The genetic studies of natural DS species is limited and, thus, we aimed to investigate seed DS through the Arabidopsis mutant abi3-6. Seeds of this mutant resemble the phenotype of those from natural DS species. It presents an attractive model as the seeds display DS when shed but are DT at the mid-development. We observed large phenotypical differences between the seeds dried inside or outside the siliques for both mutant and wild type. Desiccation of seeds inside the siliques appeared to be slower, allowing wild type seeds to survive desiccation as early as 11 days after flowering (daf). The abi3-6 seeds achieved maximum survival when dried inside the siliques at 16 daf after which DT decreased continuously until becoming completely DS at the mature stage.
RNA-seq was performed on both abi3-6 and wild type seeds at 10, 11, 16 and 18 daf, aiming to study the early and late acquisition of DT in both genotypes. The observed transcriptomic changes may contribute to the understanding of acquisition and loss of DT in seeds. Understanding the mechanisms underlying seed DS may provide a basis to develop methods for conservation of DS-seeded species.