Abstract Detail

The impact of climate change on plant physiology in natural and agricultural systems

Moroenyane, Itumeleng [1], Yergeaue, Etienne [2].

Engineering Plant-Microbe Interactions to Promote Host Health and Resilience.

Ongoing global climate change has unpredictable consequences for agriculture, changing the prevalence of pathogens and the severity of the diseases they cause. To maintain food security, we must improve our ability to protect crop plants without damaging the environment with potentially toxic synthetic chemicals. Emerging research shows that the plant microbiome significantly affects immunity, nutrient acquisition, and stress tolerance in plants, similar to the gut microbiome in animals. The plant microbiome consists of the combined microbial communities that reside on and within the plant; these communities have an intrinsic relationship with their hosts, and some confer benefits to the plant host. The plant microbiome is recognised as an extension of the plant immune response and agents that abet stress. Although the role of stress in influencing the plant microbiome is well documented, a comprehensive understanding of successional patterns and prevailing assembly processes of soybean-associated microbes is still lacking. Here, we investigate different soybean microbial communities' spatial and temporal colonisation patterns and their overall ecological assembly processes. The overarching hypothesis was that there are spatial and temporal microbial niches spaces within the soybean microbiome, and these niche spaces are under strict plant-mediated selection. The results highlighted that there were interactions between spatial and temporal dynamics that influenced microbiome diversity patterns. Moreover, it emphasised the existence of a strong temporal dependence of communities. Additionally, we focused on elucidating the prevailing assembly processes across spatial and temporal axes. Using complementary community assembly models, we highlighted that the plant compartment and developmental stage modulated the balance between niche-based and neutral processes. Also, it showed the importance of dispersal limitations in structuring plant microbiomes. Lastly, we contrasted the different colonisation patterns of seed and soil microbiomes. Using a reductionist approach, we used near-axenic seedlings, which were inoculated with varying microbiome sources. We highlighted that the seed microbiome colonised the shoot compartment during early developmental stages, whilst the soil microbiome colonised the rhizosphere. The seed microbiome was capable of outcompeting members of the rhizosphere to colonise the endophytic space quickly. Different microbiome sources also influenced the abundance of N- cycling genes across all plant compartments, with an increased abundance of N-cycling genes in the soil treatment. Overall, this work shows that the soybean microbiome is temporally nested, and microbiome sources influenced colonisation patterns. Plant-mediated selection along with dispersal limitation played a role in their assembly. This adds to ongoing efforts to manipulate plant microbiomes for increased beneficial services and more sustainable agriculture. This work therefore aims to improve our understand of plant stress tolerance from a holobiont point of view (plants and their associated microbes), focusing on plant innate microbiome, to enhance plant resistance to biotic (pathogens) and abiotic stress (e.g. drought, heat).

1 - Institut National De La Recherche Scientifique , Armand-Frappier Santè Biotechnologie, 531 Boulevard Des Prairies, Laval, QC, H7V 1B7, Canada
2 - Institut National de la Recherche Scientifique, Armand Frappier Santé Biotechnologié, 531 boulevard des Prairies, Laval, Qc, H7V 1B7, Canada

Plant growth-promoting bacteria
plant-microbe interactions

Presentation Type: Colloquium Presentations
Number: C1010
Abstract ID:454
Candidate for Awards:None

Copyright © 2000-2022, Botanical Society of America. All rights reserved