From 01/12/2021 to 31/08/2022, focus has been made on the first objective of the project. This includes:
(i) Accessions have been selected based on their diversity and their availability of sequences in www.1001genomes.com then ordered or NASC. Genotypes have been grown accordingly to the data provided by NASC on flowering time and vernalization needs in order to grow all the genotypes in triplicates randomized within the same greenhouse to obtain comparable levels of seed production. Out of 193 genotypes selected, 186 genotypes reached seed production.
Next, we analysed dormancy at single seed level. We established a protocol to quantify single seed dormancy using parameters of U1684 and U1090 (Uniformity 16/10 to 84/90, time of imbibition to go from 16/10% of total germination to 84/90%) as calculated automatically using Germinator (Joosen et al., 2010). Experimental time has been done per genotype depending on their dormancy level as checked on a weekly basis on total seed pool.
Other physiological parameters have also been recorded: number of seeds per silique (186 genotypes), individual seed size using (BoxSeed®), plant height and total number of seeds per plant (yield). Those data can further be used by the laboratory to perform GWAS on individual seed size variation.
Out of our preliminary data, we have been able to characterize genotypes with variation in single seed dormancy levels. First, we characterized candidates displaying opposite single seed dormancy phenotypes, i.e. high and low. Those genotypes can be then later analysed for single seed RNAseq and help with the identification of new putative regions involved in single seed dormancy.
Within the timeframe of the project (01/12/2021 to 31/08/2022), we have been able to produce the plant material and start the physiological characterization of the accessions. Low and high varaibel accessions has been selected and interesting candidates have been found in order to analyse further the genetic regulation of single seed dormancy.
Those preliminary data have been presented and discussed as a poster at two scientific meetings:
As a poster and oral at “IHC2022” (International Horticultural Congress 2022).
Poster: “A floral induction system to analyze seed lot intra variability in Arabidopsis and perspectives for horticultural species seed production”
Oral: “Role of seeds and seed sector in human health : « One Health » approach”
and as a poster at "10th conference of the Polish Society of Plant Experimental Biology".
“Single seed dormancy in Arabidopsis thaliana: identification of novel regulators and perspectives of application”