Sterile sentinels and MinION sequencing capture active soil microbial communities that differentiate crop rotations.

Background: Soil microbial communities are difficult to measure and critical to soil processes. The bulk soil microbiome is highly diverse and spatially heterogeneous, which can make it difficult to detect and monitor the responses of microbial communities to differences or changes in management, such as different crop rotations in agricultural research. Sampling a subset of actively growing microbes should promote monitoring how soil microbial communities respond to management by reducing the variation contributed by high microbial spatial and temporal heterogeneity and less active microbes.

Crop rotational diversity can mitigate climate-induced grain yield losses.

Diversified crop rotations have been suggested to reduce grain yield losses from the adverse climatic conditions increasingly common under climate change. Nevertheless, the potential for climate change adaptation of different crop rotational diversity (CRD) remains undetermined. We quantified how climatic conditions affect small grain and maize yields under different CRDs in 32 long-term (10-63 years) field experiments across Europe and North America.

Comparative measurements of arbuscular mycorrhizal fungal responses to agricultural management practices.

Arbuscular mycorrhizal (AM) fungi are considered to be a key group of soil organisms for assessments of soil biological properties and developing relationships among crop production management practices, soil properties, crop performance, and ecosystem services. In a field study of cover crop treatments established during the transition from small grains to corn (Zea mays L), we assessed multiple measures of AM fungal responses to the management treatments: soil propagule numbers, biomass via lipid biomarkers, and root colonization extent. Our objectives were to determine response variables that reliably distinguished cover crop treatments and formed consistent relationships with grain yield, plant biomass, and mineral nutrient concentrations of the following corn crop.

Response of Soil Surface Greenhouse Gas Fluxes to Crop Residue Removal and Cover Crops under a Corn-Soybean Rotation.

Excessive crop residue returned to the soil hinders farm operations, but residue removal can affect soil quality. In contrast, cover cropping can return additional residue to the soil and improve soils and environmental quality compared with no cover cropping. Residue and cover crop impacts on soil surface greenhouses gas (GHG) emissions are undetermined and site specific.

Previous crop and rotation history effects on maize seedling health and associated rhizosphere microbiome.

To evaluate crop rotation effects on maize seedling performance and its associated microbiome, maize plants were grown in the greenhouse in soils preceded by either maize, pea, soybean or sunflower. Soils originated from a replicated field experiment evaluating different four-year rotation combinations. In the greenhouse, a stressor was introduced by soil infestation with western corn rootworm (WCR) or Fusarium graminearum.

Insect infestations, incidence of viral plant diseases, and yield of winter wheat in relation to planting date in the northern Great Plains.

Planting date effects on arthropod infestation and viral plant disease are undocumented for winter wheat, Triticum aestivum L., in South Dakota and the northern Great Plains. Winter wheat was planted over three dates (early, middle, and late; generally from late August to late September) to determine the effect on abundance of insect pests, incidence of plant damage, incidence of viral plant disease, and grain yield.