Drainage Water Storage for Improved Resiliency and Environmental Performance of Agricultural Landscapes

Drained lands, which include some of the most productive lands in the world, can experience both water excess and water deficit within a year. Storing drained water within the landscape could increase the sustainability of water for agriculture, particularly as intense rainfall and prolonged summer drought continue to increase under future climate change. A team of researchers and extension specialists from nine states are currently working towards a vision of transforming the process of designing and implementing agricultural drainage to include storage through the use of controlled drainage, saturated buffers, and drainage water recycling (i.e. capture, storage, and reuse). Field research data from experimental drainage sites from across the U.S. Corn Belt have been brought together in a database to support synthesis and modeling to determine economic and environmental impacts of drainage water storage. Results from this effort will extend the strategies and tools to agricultural producers, the drainage industry, watershed managers, agencies, and policy makers, and educate the next generation of engineers and scientists to design drainage systems that include water storage in the landscape

Osteogenic lineage restriction by osteoprogenitors cultured on nanometric grooved surfaces – the role of focal adhesion maturation

The differentiation of progenitor cells is dependent on more than biochemical signalling. Topographical cues in natural bone extracellular matrix guide cellular differentiation through the formation of focal adhesions, contact guidance, cytoskeletal rearrangement and ultimately gene expression. Osteoarthritis and a number of bone disorders present as growing challenges for our society. Hence, there is a need for next generation implantable devices to substitute for, or guide, bone repair in vivo. Cellular responses to nanometric topographical cues need to be better understood in vitro in order to ensure the effective and efficient integration and performance of these orthopaedic devices. In this study, the FDA approved plastic polycaprolactone, was embossed with nanometric grooves and the response of primary and immortalised osteoprogenitor cells observed. Nanometric groove dimensions were 240 nm or 540 nm deep and 12.5 μm wide. Cells cultured on test surfaces followed contact guidance along the length of groove edges, elongated along their major axis and showed nuclear distortion, they formed more focal complexes and a lower proportions of mature adhesions relative to planar controls. Down-regulation of the osteoblast marker genes RUNX2 and BMPR2 in primary and immortalised cells was observed on grooved substrates. Down-regulation appeared to directly correlate with focal adhesion maturation, indicating the involvement of ERK 1/2 negative feedback pathways following integrin mediated FAK activation

Three Pseudomonas putida FNR Family Proteins with Different Sensitivities to O-2

The Escherichia coli fumarate-nitrate reduction regulator (FNR) protein is the paradigm for bacterial O2-sensing transcription factors. However, unlike E. coli, some bacterial species possess multiple FNR proteins that presumably have evolved to fulfill distinct roles. Here, three FNR proteins (ANR, PP_3233, and PP_3287) from a single bacterial species, Pseudomonas putida KT2440, have been analyzed. Under anaerobic conditions, all three proteins had spectral properties resembling those of [4Fe-4S] proteins. The reactivity of the ANR [4Fe-4S] cluster with O2 was similar to that of E. coli FNR, and during conversion to the apo-protein, via a [2Fe-2S] intermediate, cluster sulfur was retained. Like ANR, reconstituted PP_3233 and PP_3287 were converted to [2Fe-2S] forms when exposed to O2, but their [4Fe-4S] clusters reacted more slowly. Transcription from an FNR-dependent promoter with a consensus FNR-binding site in P. putida and E. coli strains expressing only one FNR protein was consistent with the in vitro responses to O2. Taken together, the experimental results suggest that the local environments of the iron-sulfur clusters in the different P. putida FNR proteins influence their reactivity with O2, such that ANR resembles E. coli FNR and is highly responsive to low concentrations of O2, whereas PP_3233 and PP_3287 have evolved to be less sensitive to O2

A novel member of the let-7 microRNA family is associated with developmental transitions in filarial nematode parasites

Background: Filarial nematodes are important pathogens in the tropics transmitted to humans via the bite of blood sucking arthropod vectors. The molecular mechanisms underpinning survival and differentiation of these parasites following transmission are poorly understood. microRNAs are small non-coding RNA molecules that regulate target mRNAs and we set out to investigate whether they play a role in the infection event. Results: microRNAs differentially expressed during the early post-infective stages of Brugia pahangi L3 were identified by microarray analysis. One of these, bpa-miR-5364, was selected for further study as it is upregulated ~12-fold at 24 hours post-infection, is specific to clade III nematodes, and is a novel member of the let-7 family, which are known to have key developmental functions in the free-living nematode Caenorhabditis elegans. Predicted mRNA targets of bpa-miR-5364 were identified using bioinformatics and comparative genomics approaches that relied on the conservation of miR-5364 binding sites in the orthologous mRNAs of other filarial nematodes. Finally, we confirmed the interaction between bpa-miR-5364 and three of its predicted targets using a dual luciferase assay. Conclusions: These data provide new insight into the molecular mechanisms underpinning the transmission of third stage larvae of filarial nematodes from vector to mammal. This study is the first to identify parasitic nematode mRNAs that are verified targets of specific microRNAs and demonstrates that post-transcriptional control of gene expression via stage-specific expression of microRNAs may be important in the success of filarial infection

Data from: Testing rangeland health theory in the Northern Great Plains

• Correctly assessing whether rangeland ecosystem services are stable, improving, or degrading is of global importance. Soil aggregate stability (SAS) is widely used to infer rangeland health, partly because high SAS is thought to reduce runoff by increasing infiltration. We studied the sensitivity of SAS to grazing and other disturbances, the effects of SAS on infiltration, and the utility of alternative indicators of infiltration in the Northern Great Plains.• To test grazing effects on SAS, we compared SAS between paired areas that were lightly to moderately grazed or excluded from grazing for 6 years. Additionally, we compared SAS between grazed and not-grazed plots of a two-year controlled grazing experiment with moderate and severe grazing. Also, we applied herbicide, mowing, and fungicide treatments to test SAS responses to disturbances more generally, as well as effects of SAS and other factors on infiltration. To more generally test for a SAS-infiltration relationship, we performed a meta-analysis of our data combined with other data from the region. • Grazing often reduced stability of small macroaggregates (0.25-1 mm) in the controlled grazing experiment but not the paired grazing area experiment. Grazing had no detectible effect on SAS of larger macroaggregates (1-2 mm). Herbicide tended to reduce SAS, and mowing sometimes increased SAS. Infiltration exhibited high plot-to-plot variation and was not significantly affected by treatments. Variation in infiltration was best explained by plant community composition variables and was not explained by either SAS or other soil properties. Our meta-analysis revealed no general SAS-infiltration relationship. • Synthesis and applications. Our findings counter prevailing expectations that SAS is consistently sensitive to rangeland disturbance(s) and a leading indicator of soil water transport. Plant community composition properties were better predictors of infiltration. Our findings support theory that excessive grazing increases the prevalence of a grazing tolerant species, which was associated with low levels of infiltration irrespective of SAS

Data from: Testing rangeland health theory in the Northern Great Plains

• Correctly assessing whether rangeland ecosystem services are stable, improving, or degrading is of global importance. Soil aggregate stability (SAS) is widely used to infer rangeland health, partly because high SAS is thought to reduce runoff by increasing infiltration. We studied the sensitivity of SAS to grazing and other disturbances, the effects of SAS on infiltration, and the utility of alternative indicators of infiltration in the Northern Great Plains.• To test grazing effects on SAS, we compared SAS between paired areas that were lightly to moderately grazed or excluded from grazing for 6 years. Additionally, we compared SAS between grazed and not-grazed plots of a two-year controlled grazing experiment with moderate and severe grazing. Also, we applied herbicide, mowing, and fungicide treatments to test SAS responses to disturbances more generally, as well as effects of SAS and other factors on infiltration. To more generally test for a SAS-infiltration relationship, we performed a meta-analysis of our data combined with other data from the region. • Grazing often reduced stability of small macroaggregates (0.25-1 mm) in the controlled grazing experiment but not the paired grazing area experiment. Grazing had no detectible effect on SAS of larger macroaggregates (1-2 mm). Herbicide tended to reduce SAS, and mowing sometimes increased SAS. Infiltration exhibited high plot-to-plot variation and was not significantly affected by treatments. Variation in infiltration was best explained by plant community composition variables and was not explained by either SAS or other soil properties. Our meta-analysis revealed no general SAS-infiltration relationship. • Synthesis and applications. Our findings counter prevailing expectations that SAS is consistently sensitive to rangeland disturbance(s) and a leading indicator of soil water transport. Plant community composition properties were better predictors of infiltration. Our findings support theory that excessive grazing increases the prevalence of a grazing tolerant species, which was associated with low levels of infiltration irrespective of SAS

Above-ground plant properties are not leading indicators of grazing-induced soil carbon accrual in the Northern Great Plains

A new aim for grassland management is to increase soil organic carbon (SOC) and to offset CO2 emissions by companies. This practice of carbon ranching may be informed by grazing-induced shifts in plant biomass and diversity which may foretell changes in SOC. Unfortunately, little is known about how grazing-induced shifts in plant properties correspond with shifts in SOC stocks. To help fill this gap, we used data from a field experiment to test whether above-ground plant properties (i.e. biomass, species richness) act as leading indicators of grazing-induced SOC accrual in the Northern Great Plains. The 5-yr bovine grazing experiment had a randomized complete block design and pre-treatment data. Moderate summer grazing (control) is widely used in the Northern Great Plains, and treatments that may alter grassland vegetation and SOC included: severe summer grazing, moderate fall grazing, and severe fall grazing. Severe fall and summer grazing increased SOC but had no effect on plant species richness and biomass relative to controls. Fall moderate grazing increased above-ground plant biomass but had no effect on SOC relative to controls. Changes to grazing practices can affect SOC without measurably affecting plant properties and can affect plant properties without measurably affecting SOC. While two drivers of SOC are plant carbon inputs and microbial respiration, our study indicates that grazing-induced change in above-ground vegetation is not predictive of change in SOC