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Wheat (Triticum aestivum L.) production is necessary for global food and nutrition security. Reducing plant height is an effective strategy to increase lodging resistance, harvest index, and eventually wheat yield. Rht8 is a gibberellic acid–sensitive reduced height (Rht) gene and has been cloned. Rht8 encodes a ribonuclease H‐like (RNHL) superfamily protein that reduces plant height without reduction in coleoptile length. High‐throughput diagnostic markers are not available for precise selection of RNHL in wheat breeding. In this study, we found that different cultivars may carry 1–3 copies of RNHLs on chromosome 2D, and only 2D carries the semi‐dwarf allele of RNHL although the wild‐type RNHL allele is detected in several other chromosomes. We developed two kompetitive allele specific PCR (KASP) markers, Rht8‐KASP‐V2 and Rht8‐KASP‐V3, based on the causal variation in RNHL. The two markers co‐segregated with plant height in a recombinant inbred population and were validated in a panel of hard winter wheat breeding lines from the 2022 Regional Germplasm Observation Nursery and Regional Performance Nursery. Rht8 has not been extensively deployed in US hard winter wheat and development of the diagnostic KASP markers will facilitate Rht8 transfer to US wheat cultivars. Core Ideas: Each cultivar carries 1–3 copies of ribonuclease H‐like domains (RNHLs) on 2D and mutations in all those copies determine Rht8 phenotype.Two kompetitive allele‐specific PCR (KASP) markers were developed for the recently cloned Rht8 gene.The two markers were diagnostic for Rht8 in a wheat diversity panel.Low Rht8 frequency in US wheat suggests high potential of using Rht8 in the United States to improve US wheat production. [ABSTRACT FROM AUTHOR]

The single‐molecule electronic devices offer the ultimate solution to miniaturize integrated circuits, and subthreshold swing (SS) is the key indicator of the power consumption for single‐molecule transistors but is still quite restricted. In this study, the redox‐mediated single‐molecule transistor with a SS down to 120 mV decade−1 in the faradaic potential region via the electrochemical‐STM break junction (EC‐STM‐BJ) technique is fabricated. With an off‐state leakage current of less than 10 pA and an on/off ratio of 100, the balance between low static power consumption and a high switching ratio is achieved. The theoretical investigations reveal that the conductance tuning is from the difference of transmission in the redox process. The study provides a new strategy for the design of single‐molecule transistors with promising SS, which is essential for the potential application of single‐molecule devices. [ABSTRACT FROM AUTHOR]

The single‐molecule electronic devices offer the ultimate solution to miniaturize integrated circuits, and subthreshold swing (SS) is the key indicator of the power consumption for single‐molecule transistors but is still quite restricted. In this study, the redox‐mediated single‐molecule transistor with a SS down to 120 mV decade−1 in the faradaic potential region via the electrochemical‐STM break junction (EC‐STM‐BJ) technique is fabricated. With an off‐state leakage current of less than 10 pA and an on/off ratio of 100, the balance between low static power consumption and a high switching ratio is achieved. The theoretical investigations reveal that the conductance tuning is from the difference of transmission in the redox process. The study provides a new strategy for the design of single‐molecule transistors with promising SS, which is essential for the potential application of single‐molecule devices. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) wild relatives are rich genetic resources for genetic improvement of wheat. The short arm of rye (Secale cereale L.) chromosome 1 (1RS) contains many beneficial genes for resistance to drought, insects, and diseases, therefore the 1RS wheat translocations have been widely used in wheat breeding programs worldwide. To facilitate marker‐assisted identification of 1RS in wheat breeding, we designed a set of Kompetitive allele‐specific polymerase chain reaction (KASP) markers to detect the translocations of 1RS with long arm from wheat chromosome 1A (1RS.1AL) and 1RS with long arm from wheat chromosome 1B (1RS.1BL) based on the sequence flanking single nucleotide polymorphisms (SNPs) generated by genotyping‐by‐sequencing (GBS) between wheat and rye panels. We identified a set of three SNP markers for diagnosis and differentiation of the two 1RS translocations in wheat. Among the three KASP markers, 1AS‐05056 is 1RS specific, and clearly separated the genotypes with 1RS (1RS.1AL and 1RS.1BL) from those without the two 1RS translocations; whereas 1AS‐29875 clearly identified the 1RS.1AL translocation and 1BS‐16654 separated 1RS.1BL from 1RS.1AL. The three new KASP markers together accurately identified the presence of 1RS translocation on either 1A or 1B chromosome in a panel of 95 representative U.S. winter wheat accessions, which were further validated in two additional U.S. hard winter wheat panels. Therefore, they can be used for routine screening of 1RS.1BL and 1RS.1AL translocation lines in wheat breeding programs. Core Ideas: 1RS, 1AS, and 1BS specific SNPs were identified by analyzing GBS‐SNPs from both wheat and rye panels.Three chromosome‐arm‐specific KASPs clearly detected the 1RS.1AL and 1RS.1BL translocations in wheat.Three KASP markers were diagnostic for 1RS.1AL and 1RS.1BL in two U.S. hard winter wheat panels. [ABSTRACT FROM AUTHOR]

Using glucosamine hydrochloride as the starting material, 4‐(methoxycarbonyl)‐5‐methyl‐1‐propyl‐1H‐pyrrole‐2‐carboxylic acid (3) was initially created as an intermediate compound by cyclization and oxidation in order to create novel high temperature stable pyrrole compounds. Furthermore, Steglich esterification was used to produce N‐substituted pyrrole esters (4 a–4 t). All the new compounds were verified using nuclear magnetic resonance (1H and 13CNMR), infrared spectroscopy (IR), and high resolution mass spectrometry (HRMS). Thermogravimetry (TG), differential scanning calorimetry (DSC), and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS) techniques were used to examine the thermal behaviors of the compounds 4 f, 4 g, 4 i, and 4 q. Ester bonds from the pyrolysis products 4 g, 4 i, and 4 q might be severed which were consisted of the raw materials as well as the substrates, such as menthol, phenethyl and pyrrole derivatives which are commonly utilized in the sector of spices in foods and cigarette. [ABSTRACT FROM AUTHOR]

Our team has initiated a selective breeding program for regional strains of sugar kelp, Saccharina latissima, to improve the competitiveness of kelp farming in the United States. Within our breeding program, we also include an endemic putative species, Saccharina angustissima, locally referred to as skinny kelp. We crossed uniclonal gametophyte cultures derived from 37 wild‐collected blades representing five sugar kelp strains and one skinny kelp strain to produce 104 unique crosses. Each cross was outplanted on a near‐shore research farm located in the Gulf of Maine (GOM). After the first farming season, our results indicated that sugar kelp and skinny kelp were interfertile, and produced mature and reproductively viable sporophytes. Morphological traits of individual blades varied depending on the parental contribution (sugar vs. skinny), with significant differences found in progeny blade length, width, thickness, and in stipe length and diameter. Despite these differences, wet weight and blade density per plot showed no statistical differences regardless of the cross. Given their published genetic similarity and their interfertility shown here, S. angustissima and S. latissima may not be different species, and may each contribute genetic diversity to breeding programs aimed at meeting ocean farming and market needs. [ABSTRACT FROM AUTHOR]

Hessian fly (HF, Mayetiola destructor Say), is a destructive insect pest in most wheat (Triticum aestivum L.) growing areas worldwide. Growing resistant cultivars can effectively reduce HF damage. The wheat cultivar 'Seneca' was reported to carry resistance genes H7 on chromosome 5D and H8 with unknown location. To further validate the resistance gene locations in Seneca, a recombinant inbred line (RIL) population from Bobwhite × Seneca was genotyped using 3,330 single nucleotide polymorphism (SNP) markers generated from genotyping‐by‐sequencing (GBS) and phenotyped for HF resistance in the greenhouse experiments. Phenotypic analyses showed at least two genes conditioning HF resistance in Seneca, but none of them was mapped on chromosome 5D, as previously reported. Instead, one major gene, designated as H7, was mapped to chromosome 6A and explained 60.7–78.3% of the phenotypic variation. The other gene with a minor effect, designated as H8, was found on chromosome 2B and explained 3.2–4.7% of the phenotypic variation. Based on the physical locations of flanking markers for H7 in the Chinese Spring reference genome, H7 was physically located in a 6‐Mb interval on 6AL. This study reassigned the major gene H7 to chromosome 6A and the minor gene H8 to 2B in Seneca using a high‐density SNP map. Seventeen GBS SNPs mapped in the H7 region were converted into Kompetitive allele specific polymerase chain reaction (KASP) markers for selecting this gene in breeding. [ABSTRACT FROM AUTHOR]

BACKGROUND Understanding the variance of antioxidant in wheat grain responses to irrigation and nitrogen (N) fertiliser management will improve the nutrient quality of wheat grain. Four N rates (0, 180, 240, and 300 kg ha−1) combined with irrigation times (I0, no irrigation; I1, jointing time irrigation; I2, jointing + flowering time irrigation), were used to determine the effect of N fertilisation and irrigation on total phenolic content (TPC), phenolic acid composition, and antioxidant activity (AOA) of wheat grain. RESULTS Irrigation, N fertilisation and their interactions had significant effect on TPC, total flavonoid content (TFC), AOA, p-coumaric acid (PCA), as well as vanillic acid (VA) and chlorogenic acid (CA). I1N300 treatment had the highest TPC at Zhengzhou and Wenxian (1451.5 µg g−1 and 1397.9 µg g−1, respectively) location, while I1N240 resulted in the highest TFC (0.75 mg g−1) and VA (19.77 µg g−1) at Wenxian. TPC, TFC, AOA, ferulic acid (FA), PCA and VA increased with N application rate (from 180 to 300 kg N ha−1). CONCLUSION An appropriate irrigation and N management improved antioxidant content and AOA in wheat grain. Generally, I1N240 and I1N300 treatment resulted in the higher TPC, TFC, AOA, as well as phenolic acid, i.e. FA and VA. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]