Insights into the structure and role of seed-borne bacteriome during maize germination

Abstract

Seed germination events modulate microbial community composition, which ultimately influences seed to seedling growth performance. Here we assess the seed-borne bacteria community in disinfected and non-disinfected maize seeds and seedlings. Using a gnotobiotic system, sodium hypochlorite (1.25%, 30 min) treated-seeds showed a reduction of bacteria population size and an increase of bacteria community diversity associated with selective suppression of Burkholderia related taxon. The shift in the bacteria community composition in disinfested-seeds negatively affects germination speed, seedling growth, and reserve mobilization rates in comparison with non-disinfected maize seeds. A synthetic bacteria community formed by twelve isolates (9 Burkholderia spp.; 2 Bacillus spp. and 1 Staphylococcus sp.) obtained from natural microbiota of maize seeds herein were capable of recovering germination and seedling growth when reintroduced in disinfected seeds. Overall results showed that changes in bacterial community composition and selective reduction of Burkholderia related members dominance interfere with germination events and initial growth of the maize plantlets. By cultivation-dependent and independent approaches, we deciphered seed-maize microbiome structure, bacterial niches location, and bacterial taxon with relevant roles in seedlings growth performance. A causal relationship between seed microbial community succession and germination performance open opportunities in seed technologies to build-up microbial communities to boost plant growth and health.One sentence summarypartial removal of the seed-borne microbiota negatively affects maize seedling growth performance and altered bacteria community structure. Partial microbial recomposition, mainly with Burkholderia-related isolates, restores the germination phenotype of disinfested seeds.

Temporal Dynamics of Endogenous Bacterial Composition in Rice Seeds During Maturation and Storage, and Spatial Dynamics of the Bacteria During Seedling Growth

“…The dynamics of the seed microbiome during maturation, transferred to the next generation, and their influence on the seedlings have been the subject of many studies (Shade et al, 2017;Dos Santos et al, 2021;Kim and Lee, 2021;Bintarti et al, 2022). Endophytes of rice plants and seeds have also garnered recent attention.…”

Editorial to the Thematic Topic “Towards a more sustainable agriculture through managing soil microbiomes”

“…The work of Heijo et al (2021) added to the understanding of plant-endophyte interactions in agroecosystems by investigating the effect of diazotrophic bacterial endophyte inoculation on sweet sorghum performance depending on nitrogen fertilization doses and the sorghum cultivar. Figueiredo dos Santos et al (2021) showed that maize seedborne bacteria are crucial for germination and development of maize seedlings. Combining in vitro functional screening for plant growth promotion with whole genome sequencing provided new insights into the mechanisms of two tropical Bacillus inoculant strains on different maize genotypes (Vieira Velloso et al 2020).…”