GiPS: Genomics-informed parent selection uncovers the breeding value of wheat genetic resources

The great efforts spent in the maintenance of past diversity in genebanks are rationalized by the potential role of plant genetic resources in future crop improvement: a concept whose practical implementation has fallen short of expectations. Here, we implement genomics-informed parent selection to expedite pre-breeding without discriminating against non-adapted germplasm. We collect dense genetic profiles for a large winter wheat collection and evaluate grain yield and resistance to yellow rust in representative coresets. Genomic prediction within and across genebanks identified the best parents for PGR x elite derived crosses that outyielded current elite cultivars in multiple field trials.

Next Generation Torsional Vibration Isolation Tool Increases BHA Reliability Proven by Field Operations in North Sea

High Frequency Torsional Oscillations (HFTO) generate high torsional loads in the BHA causing cracks, damaged electronics or twist-offs. A new Torsional Vibration Isolator tool (TVI) protects the BHA by restricting vibrations to the tools between bit and TVI. Additional features have been added to the tool to automatically indicate torque overloading of the BHA and to increase torque resistance if required. This paper proves the functionality of the new features analytically, on a small-scale laboratory test and in multiple field deployments in the North Sea. New guidelines for field operations are provided. The new feature is a torsion limiter which automatically engages on reaching a critical torque threshold. The torque is then re-routed through more torque resistant BHA components. The engagement generates a characteristic signal indicating bit or BHA-overloading. The mechanical design of the new feature is presented. A criterion for engagement of the limiter and the signature indicating critical torque are analytically derived. They are experimentally validated on a scaled version of the TVI in a laboratory test. A prototype of the new tool is manufactured and deployed in multiple field operations in the North Sea previously heavily affected by HFTO. Two high-frequency measuring devices identify critical drilling situations on a scale of Milliseconds. A new guideline for utilization of this tool is developed including recommendations for BHA set-up and operational parameters. The TVI works as intended and protects the upper BHA from torsional loads generated by HFTO. The new feature engages at the predicted contact parameters. The signature indicating critical torque for the BHA was recorded and corresponds to the signature measured in the lab and predicted by the model. The TVI is best placed as close to the bit as possible, and a high-frequency measuring device in the BHA is recommended to record and transmit the contact indicators to surface. Based on field tests a parameter map for drilling torque and RPM is created that displays zones of safe operational parameters in a plain manner for field engineers. The map was validated in the field, and harmful drilling states were prevented by following the recommended drilling parameters. The next generation TVI protects BHAs from damage due to torsional vibrations. The new feature enables operations in stuck-pipe situations by increasing the torque when required. The overloading indicator prevents overstepping the torque limit of the bit and the BHA. The new parameter map and best-practice recommendations transport the learnings to the field in an easy-to-use manner.

Novel Quantitative Trait Loci for Grain Cadmium Content Identified in Hard White Spring Wheat

Cadmium (Cd) is a heavy metal that can cause a variety of adverse effects on human health, including cancer. Wheat comprises approximately 20% of the human diet worldwide; therefore, reducing the concentrations of Cd in wheat grain will have significant impacts on the intake of Cd in food products. The tests for measuring the Cd content in grain are costly, and the content is affected significantly by soil pH. To facilitate breeding for low Cd content, this study sought to identify quantitative trait loci (QTL) and associated molecular markers that can be used in molecular breeding. One spring wheat population of 181 doubled haploid lines (DHLs), which was derived from a cross between two hard white spring wheat cultivars “UI Platinum” (UIP) and “LCS Star” (LCS), was assessed for the Cd content in grain in multiple field trials in Southeast Idaho, United States. Three major QTL regions, namely, QCd.uia2-5B, QCd.uia2-7B, and QCd.uia2-7D, were identified on chromosomes 5B, 7B, and 7D, respectively. All genes in these three QTL regions were identified from the NCBI database. However, three genes related to the uptake and transport of Cd were used in the candidate gene analysis. The sequences of TraesCS5B02G388000 (TaHMA3) in the QCd.uia2-5B region and TraesCS7B02G320900 (TaHMA2) and TraesCS7B02G322900 (TaMSRMK3) in the QCd.uia2-7B region were compared between UIP and LCS. TaHMA2 on 7B is proposed for the first time as a candidate gene for grain Cd content in wheat. A KASP marker associated with this gene was developed and it will be further validated in near-isogenic lines via a gene-editing system in future studies.

On the Question of the Bäcklund Transformations and Jordan Generalizations of the Second Painlevé Equation

We demonstrate the way to derive the second Painlevé equation P2 and its Bäcklund transformations from the deformations of the Nonlinear Schrödinger equation (NLS), all the while preserving the strict invariance with respect to the Schlesinger transformations. The proposed algorithm allows for a construction of Jordan algebra-based completely integrable multiple-field generalizations of P2 while also producing the corresponding Bäcklund transformations. We suggest calling such models the JP-systems. For example, a Jordan algebra JMat(N,N) with the Jordan product in the form of a semi-anticommutator is shown to generate an integrable matrix generalization of P2, whereas the VN algebra produces a different JP-system that serves as a generalization of the Sokolov’s form of a vectorial NLS.

Influence of Time of Day on Dicamba and Glyphosate Efficacy

Renewed interest in studying auxin herbicides (WSSA group 4) is increasing due to the release of genetically engineered crop varieties that are tolerant to PRE and POST applications of specific formulations of dicamba. The development of auxin-resistant crops was in response to the development of herbicide-resistant weed species to glyphosate and other herbicides. Research was conducted at multiple field locations in Georgia in 2018 and 2019 to examine weed control when POST herbicides were applied to dicamba and glyphosate-resistant cotton at eight different points in time over a 24-hr period. Applications occurred at 1-hr prior to sunrise all the way up to midnight in one day to examine the effect of herbicide application timing on broadleaf weed control. Glyphosate, dicamba, and glyphosate plus dicamba were applied at each timing. Visual ratings of weed control were evaluated at 7, 14, 21, and 28 days after treatment (DAT). Weed control was affected by herbicide application timing. Midnight applications resulted in the lowest levels of control. Sicklepod, pitted morningglory, and prickly sida control was 49, 38, and 41% respectively. Greatest control of all three species (up to 99%) occurred from the noon to 1-hr prior to sunset application timings. Orthogonal contrasts of timing of application indicated that weed control was improved with day > night and pre-dawn > midnight.