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Genetic transformation is widely used to improve target traits and to study gene function in wheat. However, transformation efficiency depends on the physiological status of the recipient genotype and that is affected by several factors including powdery mildew (PM) infection. The widely used recipient variety Fielder is very susceptible to PM. Therefore, it would be beneficial to develop PM resistant derivatives with high regeneration ability for use in genetic transformation. In the present study PM resistant lines CB037 and Pm97033 carrying genes Pm21 and PmV, respectively, were backcrossed to Fielder with selection for PM resistance. Five lines, NT89, NT90, NT154, and WT48 with Pm21 and line FL347 with PmV were developed, identified by molecular markers and genomic in situ hybridization (GISH) or fluorescent in situ hybridization (FISH), and further subjected to detailed assessment of agronomic traits and regeneration ability following genetic transformation capacity. Lines FL347, WT48, NT89 and NT154 assessed as being equal to, or superior, to Fielder in regeneration and transformation ability are recommended as suitable materials for the replacement of Fielder for wheat gene transfer and genome editing study.

Histone acetylation is the earliest and most well-characterized of post-translation modifications. It is mediated by histone acetyltransferases (HAT) and histone deacetylases (HDAC). Histone acetylation could change the chromatin structure and status and further regulate gene transcription. In this study, nicotinamide, a histone deacetylase inhibitor (HDACi), was used to enhance the efficiency of gene editing in wheat. Transgenic immature and mature wheat embryos harboring a non-mutated GUS gene, the Cas9 and a GUS-targeting sgRNA were treated with nicotinamide in two concentrations (2.5 and 5 mM) for 2, 7, and 14 days in comparison with a no-treatment control. The nicotinamide treatment resulted in GUS mutations in up to 36% of regenerated plants, whereas no mutants were obtained from the non-treated embryos. The highest efficiency was achieved when treated with 2.5 mM nicotinamide for 14 days. To further validate the impact of nicotinamide treatment on the effectiveness of genome editing, the endogenous TaWaxy gene, which is responsible for amylose synthesis, was tested. Utilizing the aforementioned nicotinamide concentration to treat embryos containing the molecular components for editing the TaWaxy gene, the editing efficiency could be increased to 30.3% and 13.3%, respectively, for immature and mature embryos in comparison to the 0% efficiency observed in the control group. In addition, nicotinamide treatment during transformation progress could also improve the efficiency of genome editing approximately threefold in a base editing experiment. Nicotinamide, as a novel approach, may be employed to improve the editing efficacy of low-efficiency genome editing tools such as base editing and prime editing (PE) systems in wheat.

Wheat nutrition and processing-quality are primarily based on the endosperm ingredients. However, the effect of embryos on grain traits and components remains unclear. In this study, we found that in the cross-pollinated and self-pollinated progenies of the four wheat mtl mutants (mtl-A, mtl-AD, mtl-BD, and mtl-ABD) the haploid induction rates were 0–15.6% and 0–14.1%, and the embryo abortion rates were 0–27.4% and 0–24.1%, respectively, in which mtl-A had no effect on haploid induction and embryo development. The embryoless grains (ELG) were comparable to the normal grains (NG) from mtl-AD, mtl-BD, and mtl-ABD in grain length, grain width and thousand-kernel weight, but the grain traits were significantly less than those in NG from mutant mtl-A. During grain filling period, mtl-ABD had similar ELG ratio and amount of starch granule (SG) and protein body (PB) in ELG and NG. At maturity stage, the morphological features of A-type and B-type SG in ELG were similar to those in NG in mtl mutants; however, amylose, gliadin, and glutenin contents were higher in ELG, and total starch, albumin and globulin contents were higher in NG. Our results clarified the effect of the wheat mtl mutants on haploid induction and grain traits and nutrition composition in this crop, and provided new clues for studying the development of embryo and endosperm and their interaction in plants.

Wheat bread-making quality can be improved by use of high-molecular-weight glutenin subunits (HMW-GSs) from wild relatives. Aegilops longissima is a close relative of wheat that contains a number of HMW-GS-encoding genes including 1Slx2.3*. In this study, transgenic wheat lines overexpressing 1Slx2.3* were obtained by Agrobacterium-mediated transformation and used to investigate the genetic contribution of 1Slx2.3* to wheat flour-processing quality. The 1Slx2.3* transgene was stably inherited and expressed over generations. Expression of 1Slx2.3* increased the relative expression of 1Dx2 and 1Dy12 and reduced that of 1By18 during grain development. In general, integration of 1Slx2.3* stimulated the accumulation of endogenous HMW-GSs and low-molecular-weight glutenin subunits in wheat kernels, greatly increasing the glutenin:gliadin ratio and resulting in faster formation of protein bodies in the endosperm during grain development. A wheat material with improved flour-making quality was developed in which 1Slx2.3* improved wheat bread-making quality. [ABSTRACT FROM AUTHOR]

In this paper, tetrahydrofurfuryl-functionalized polystyrene nanoparticles (TFPNs) were evaluated as collectors in low-rank coal flotation. A series of TFPNs were prepared by immobilizing tetrahydrofurfuryl groups onto the surface of polystyrene nanoparticles (PNs), and further characterized in terms of their size, shape, surface charge and surface functionalization group concentration (SFGC). The coal flotation performance using TFPNs was compared to that using PNs and diesel oil (DO). The interaction mechanisms between TFPNs and low-rank coal were also discussed. The results show that TFPNs gave higher recovery than that given by PNs and DO. Smaller TFPNs were more effective flotation collectors. The recovery of TFPNs increased firstly and then decreased with SFGC. TFPNs can specifically deposit onto the low-rank coal particles with the hydrogen bonding function between tetrahydrofurfuryl groups and oxygen-containing functional groups, and promote low-rank coal flotation by increasing the hydrophobicity and roughness of coal particle surface with the adsorbed TFPNs. It was demonstrated that TFPNs introduced a new class of collectors for low rank coal flotation. [ABSTRACT FROM AUTHOR]

Low-rank coals are difficult to float using common hydrocarbon oily collectors, such as dodecane and diesel. In this investigation, a mixture of dodecane and n-valeraldehyde was used as a collector to enhance low-rank coal flotation. The changes of the contact angle and surface functional groups of low-rank coal were measured before and after different collectors' adsorption to indicate its absorption mechanism. Surface tension of different collectors was also measured to identify its spreading performance. The results showed that the flotation performance using the mixture as a collector was much better than that using dodecane or n-valeraldehyde solely. When used the mixture of dodecane and n-valeraldehyde as collector, dodecane primarily covers the hydrophobic sites while n-valeraldehyde primarily covered the hydrophilic sites by hydrogen bond promoting adsorption of dodecane at these sites. There existed synergistic effect between dodecane and n-valeraldehyde. Additionally, n-valeraldehyde can reduce the surface tensions to improve the spreading performance of mixed collector on low-rank coal surface. The improvement both in adsorption and spreading was responsible for the enhancement of low-rank coal flotation by using the mixture. [ABSTRACT FROM AUTHOR]