EXT 12 Use of multispecies annual forage crops to promote healthy soil microbial communities and improve forage yield and sustainability
- Project Lead: Luke Bainard, Research Scientist, Agriculture and Agri-Food Canada, Swift Current, Saskatchewan
- MBFI Location(s):Brookdale Farm
- Collaborating Partners:Mike Schellenberg, Research Scientist, AAFC
- Start Date: 2016
- Status: Completed November 2017
The first objective is to determine the effect of increasing crop diversity on forage productivity and the diversity and functional activity of soil microbial communities. The second is to determine the effect of plant functional groups and functional redundancy on forage productivity and diversity of microbial communities. And, the relative contribution of soil microbial communities to forage yield will be determined.
- To determine the effect of increasing crop diversity on forage productivity and the diversity and functional activity of soil microbial communities.
- To determine the effect of plant functional groups and functional redundancy on forage productivity and diversity of microbial communities.
- To determine the relative contribution of soil microbial communities to forage yield.
This project aims to identify the benefits of diversity above and belowground and their potential contributions to sustainable and resilient forage production systems. Increasing plant diversity (both species and functional group richness) has the potential to increase crop productivity due to trait complementarity and increased functional redundancy, which reduces competition and increases stability. However, it is unclear how multi-species annual forage crop mixtures impact the function and diversity of soil microbial communities, which play an integral role in many important belowground ecosystem services. We plan to use two separate field studies to determine the effects of annual crop (1) diversity and (2) functional redundancy on soil microbial communities and forage productivity. The first field study at Brookdale and Swift Current is designed to broadly test the impact of increasing crop diversity, and the second field study at Swift Current will involve smaller plots to test the effects of plant functional groups (i.e., C3, C4, legumes, and brassicas) and functional redundancy on soil health and forage productivity. A combination of traditional and advanced molecular biology tools will be used to assess the taxonomic and functional microbial diversity. We will specifically determine (i) microbial biomass and activity, and (ii) composition and abundance of microbial taxa and functional groups/guilds (i.e., mutualists, saprophytes, pathogens, etc.). This approach will provide insights into the effects of crop mixtures and functional groups on the diversity and functional activity of soil microbial communities and their relative contribution to forage productivity.
As of October 2016 - During the first field season we observed good growth in the mixtures. Most plant species performed well, while other species underperformed likely due to poor emergence or competetive ability. Weather conditions may have also impacted the performance of the mixtures as we had above average precipitation at the field sites, which impacted site management (e.g., seeding dates and weed control). In late September, grazing took place at the Brookdale site, which will allow us to monitor the effects of grazing the mixtures on soil health and forage productivity during the second year of the project.