ABSTRACT: Seeds are crucial for plant reproduction, dispersal, and agriculture. Seed quality and vigour greatly impact crop production, referring to their ability to germinate rapidly and uniformly under varying environmental conditions, producing healthy seedlings that can withstand biotic and abiotic stress accentuated by global climate change. During germination, seeds release exudates, complex mixtures of organic and inorganic molecules, into the micro-environment surrounding them, known as the spermosphere. These exudates play a pivotal role in seedling development and overall plant fitness by influencing microbial selection, growth, and interactions in the spermosphere, ultimately shaping the plant's microbiome. To understand the composition and functional properties of germinating seed exudates, we conducted our study using different common bean (Phaseolus vulgaris L.) genotypes. Seeds were harvested in the year 2020 from eight different common bean genotypes (French commercial cultivars of Phaseolus vulgaris) cultivated in two different locations from the FNAMS field experimental stations: Gers in South-west of France (43.956991, 0.392127) and Maine et Loire (47.470532, -0.394526) in the Loire Valley. The common bean genotypes namely, VEZ, CON, CAP, FAC, FLA, LIN, DEE and VAN were chosen to represent the highest diversity among breeding programmes and qualitative seed traits in France by the seed company Vilmorin-Mikado SAS (Limagrain group). One seed lot corresponds to seeds from one genotype produced in one location. Independent biological replicates were conducted for each seed lot. Thus, 48 samples were analyzed, corresponding to three replicates of eight genotypes produced in two locations. Spermosphere collection of germinating seeds involved the imbibition of 30 seeds for each sample at four distinct time intervals: 2, 8, 16, and 24 hours. The collected spermosphere, consisting of the water surrounding germinating seeds, was gathered for each time interval and subsequently pooled. Subsequently we investigated the diversity of metabolites of each pooled spermosphere using untargetted metabolomic (LC-MS/MS) analysis.
Massimiliano CORSO 
