Engineering In Situ Soil and Plant Microbiomes To Improve Agricultural Productivity

The world’s population is predicted to reach 9 billion people by 2050 thus increasing crop production on current agricultural land to meet the rising demand for food is paramount. Farmers routinely manage both plant and soil nutrition to increase crop yields. However, active management of in situ soil and plant microbiomes to improve productivity is uncommon. Here, we present a patented technology aiming to reliably engineer soil and plant microbiomes to increase crop production. Bioprime is a ferment of molasses that can be applied as seed coating, or as foliar and soil spray

A Fast and Inexpensive Molecular Biological Assay to Assess Soil Health

Soil health and biology is capturing public imagination due to its significance in organic and regenerative agriculture and its role in mitigating climate change (a location for potential carbon sequestration). Programs centred on soil health are supported by farmers and funding bodies such as the Soil Biology Initiative (Grains Research and Development Corporation), the National Landcare Program, and the Cooperative Research Centre for High Performance Soils. Additionally, global businesses are diverting resources into understanding soil and crop microbiomes to develop novel technologies that increase soil health and crop productivity to commercialise a variety of products including soil amendments (e.g. sea weeds, humic acids, other prebiotics) or microbial inocula (often termed “biologicals”, “probiotics”, “biopesticides”, or “biofungicides”)

Test of viability measures in starved, sedimentary, anaerobic bacterial isolates and in a temperature stressed estuarine sedimentary microbial community : insights for deep biosphere studies

Marine sediments harbour vast and diverse prokaryotic communities. With ongoing burial and ageing of respective sediment layers, however, available organic matter becomes more recalcitrant. Thus, sedimentary microorganisms face starvation and ultimately death. Nonetheless, live and active cells are present in old and deeply buried sediments, up to 111 Ma (Roussel et al., 2008). During IODP Leg 307 an organic-matter poor, cold-water, buried coral carbonate mound was sampled. Nineteen isolates, mainly Proteobacteria, were obtained from the mound and surrounding sediments. Additionally, one putative new species belonging to the genus Ornithinimicrobium (Actinobacteria) was isolated. Strains were subsequently phylogenetically and phenotypically characterised. Selected isolates and other sedimentary bacteria were subsequently subjected to anaerobic starvation-survival experiments and their responses to substrate limitation were compared to those of near-surface relatives. All strains survived long periods of starvation (incubated up to 3 years). This was confirmed by constant total cell counts and only slowly increasing proportions of dead cells (20% after one year). Culturability and FISH detectability decreased with time but radiotracer experiments conducted after starvation confirmed viability and potential metabolic activity of many strains. No significant correlations between FISH detectability and other viability measures occurred. Instead starvation time was significantly positively correlated with percentages of dead cells and inversely with culturability. Pure culture starvation experiments were complemented by a study on an estuarine, surface-sediment microbial community, which was stressed in sediment slurry sequential heating experiments. This mimicked burial and resulted in decreasing total counts, culturability, and FISH detcctability but these were still present even after heating to 90 °C. Temperatures above 42 °C were significantly correlated with the reduction of total cells and FISH detectability This project showed that marine sedimentary microbes maintain high levels of viability and culturability during long-term anaerobic starvation and during sequential heating to mimic burial this is consistent with the large cell population in sub-seafloor sediments

Subsurface microbiology and biogeochemistry of a deep, cold-water carbonate mound from the Porcupine Seabight (IODP Expedition 307)

The Porcupine Seabight Challenger Mound is the first carbonate mound to be drilled (∼270 m) and analyzed in detail microbiologically and biogeochemically. Two mound sites and a non-mound Reference site were analyzed with a range of molecular techniques [catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), quantitative PCR (16S rRNA and functional genes, dsrA and mcrA), and 16S rRNA gene PCR-DGGE] to assess prokaryotic diversity, and this was compared with the distribution of total and culturable cell counts, radiotracer activity measurements and geochemistry. There was a significant and active prokaryotic community both within and beneath the carbonate mound. Although total cell numbers at certain depths were lower than the global average for other subseafloor sediments and prokaryotic activities were relatively low (iron and sulfate reduction, acetate oxidation, methanogenesis) they were significantly enhanced compared with the Reference site. In addition, there was some stimulation of prokaryotic activity in the deepest sediments (Miocene, > 10 Ma) including potential for anaerobic oxidation of methane activity below the mound base. Both Bacteria and Archaea were present, with neither dominant, and these were related to sequences commonly found in other subseafloor sediments. With an estimate of some 1600 mounds in the Porcupine Basin alone, carbonate mounds may represent a significant prokaryotic subseafloor habitat

Engineering In Situ Soil and Plant Microbiomes To Improve Agricultural Productivity

The world’s population is predicted to reach 9 billion people by 2050 thus increasing crop production on current agricultural land to meet the rising demand for food is paramount. Farmers routinely manage both plant and soil nutrition to increase crop yields. However, active management of in situ soil and plant microbiomes to improve productivity is uncommon. Here, we present a patented technology aiming to reliably engineer soil and plant microbiomes to increase crop production. Bioprime is a ferment of molasses that can be applied as seed coating, or as foliar and soil spray

Magnetic particle-mediated magnetoreception

Behavioural studies underpin the weight of experimental evidence for the existence of a magnetic sense in animals. In contrast, studies aimed at understanding the mechanistic basis of magnetoreception by determining the anatomical location, structure and function of sensory cells have been inconclusive. In this review, studies attempting to demonstrate the existence of a magnetoreceptor based on the principles of the magnetite hypothesis are examined. Specific attention is given to the range of techniques, and main animal model systems that have been used in the search for magnetite particulates. Anatomical location/cell rarity and composition are identified as two key obstacles that must be addressed in order to make progress in locating and characterizing a magnetite-based magnetoreceptor cell. Avenues for further study are suggested, including the need for novel experimental, correlative, multimodal and multidisciplinary approaches. The aim of this review is to inspire new efforts towards understanding the cellular basis of magnetoreception in animals, which will in turn inform a new era of behavioural research based on first principles

Co-application of a biosolids product and biochar to two coarse-textured pasture soils influenced microbial N cycling genes and potential for N leaching

Co-application of biochar and biosolids to soil has potential to mitigate N leaching due to physical and chemical properties of biochar. Changes in N cycling pathways in soil induced by co-application of biological amendments could further mitigate N loss, but this is largely unexplored. The aim of this study was to determine whether co-application of a biochar and a modified biosolids product to three pasture soils differing in texture could alter the relative abundance of N cycling genes in soil sown with subterranean clover. The biosolids product contained lime and clay and increased subterranean clover shoot biomass in parallel with increases in soil pH and soil nitrate. Its co-application with biochar similarly increased plant growth and soil pH with a marked reduction in nitrate in two coarse textured soils but not in a clayey soil. While application of the biosolids product altered in silico predicted N cycling functional genes, there was no additional change when applied to soil in combination with biochar. This supports the conclusion that co-application of the biochar and biosolids product used here has potential to mitigate loss of N in coarse textured soils due to N adsoption by the biochar and independently of microbial N pathways