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Wheat is one of the most important food crops, both in China and worldwide. Wheat production is facing extreme stresses posed by different diseases, including Fusarium head blight (FHB), which has recently become an increasingly serious concerns. FHB is one of the most significant and destructive diseases affecting wheat crops all over the world. Recent advancements in genomic tools provide a new avenue for the study of virulence factors in relation to the host plants. The current review focuses on recent progress in the study of different strains of Fusarium infection. The presence of genome-wide repeat-induced point (RIP) mutations causes genomic mutations, eventually leading to host plant susceptibility against Fusarium invasion. Furthermore, effector proteins disrupt the host plant resistance mechanism. In this study, we proposed systematic modification of the host genome using modern biological tools to facilitate plant resistance against foreign invasion. We also suggested a number of scientific strategies, such as gene cloning, developing more powerful functional markers, and using haplotype marker-assisted selection, to further improve FHB resistance and associated breeding methods. [ABSTRACT FROM AUTHOR]

Summary: Barley yellow dwarf viruses (BYDVs) cause widespread damage to global cereal crops. Here we report a novel strategy for elevating resistance to BYDV infection. The 17K protein, a potent virulence factor conserved in BYDVs, interacted with barley IMP‐α1 and ‐α2 proteins that are nuclear transport receptors. Consistently, a nuclear localization signal was predicted in 17K, which was found essential for 17K to be transported into the nucleus and to interact with IMP‐α1 and ‐α2. Reducing HvIMP‐α1 and ‐α2 expression by gene silencing attenuated BYDV‐elicited dwarfism, accompanied by a lowered nuclear accumulation of 17K. Among the eight common wheat CRISPR mutants with two to four TaIMP‐α1 and ‐α2 genes mutated, the triple mutant α1aaBBDD/α2AAbbdd and the tetra‐mutant α1aabbdd/α2AAbbDD displayed strong BYDV resistance without negative effects on plant growth under field conditions. The BYDV resistance exhibited by α1aaBBDD/α2AAbbdd and α1aabbdd/α2AAbbDD was correlated with decreased nuclear accumulation of 17K and lowered viral proliferation in infected plants. Our work uncovers the function of host IMP‐α proteins in BYDV pathogenesis and generates the germplasm valuable for breeding BYDV‐resistant wheat. Appropriate reduction of IMP‐α gene expression may be broadly useful for enhancing antiviral resistance in agricultural crops and other economically important organisms. [ABSTRACT FROM AUTHOR]

In this paper, an optical fiber humidity sensor based on acrylate AB adhesive film is studied, and two methods—a bubbling method and a dual pressure assisted method—for preparing thin films are proposed. The forms will make the thin film lighter and make the sensor more sensitive. Using a glass tube to connect the acrylate AB adhesive film to the single mode optical fiber, the humidity sensor is obtained. Through humidity response experiments, the sensor's sensitivity reaches 167.5 pm/% RH, and the response time reaches 4.8 s/% RH. At the same time, the experiments show that the sensor has good repeatability and stability. Finally, the influence of temperature on the working process is analyzed, and we provide a method for improvement through FBG. [ABSTRACT FROM AUTHOR]

Summary: Tiller angle is one of the most important agronomic traits and one key factor for wheat ideal plant architecture, which can both increase photosynthetic efficiency and greatly enhance grain yield. Here, a deacetylase HST1‐like (TaHST1L) gene controlling wheat tiller angle was identified by the combination of a genome‐wide association study (GWAS) and bulked segregant analysis (BSA). Ethyl methane sulfonate (EMS)‐mutagenized tetraploid wheat lines with the premature stop codon of TaHST1L exhibited significantly smaller tiller angles than the wild type. TaHST1L‐overexpressing (OE) plants exhibited significantly larger tiller angles and increased tiller numbers in both winter and spring wheat, while TaHST1L‐silenced RNAi plants displayed significantly smaller tiller angles and decreased tiller numbers. Moreover, TaHST1L strongly interacted with TaIAA17 and inhibited its expression at the protein level, and thus possibly improved the content of endogenous auxin in the basal tissue of tillers. The transcriptomics and metabolomics results indicated that TaHST1L might change plant architecture by mediating auxin signal transduction and regulating endogenous auxin levels. In addition, a 242‐bp insertion/deletion (InDel) in the TaHST1L‐A1 promoter altered transcriptional activity and TaHST1L‐A1b allele with the 242‐bp insertion widened the tiller angle of TaHST1L‐OE transgenic rice plants. Wheat varieties with TaHST1L‐A1b allele possessed the increased tiller angle and grain yield. Further analysis in wheat and its progenitors indicated that the 242‐bp InDel possibly originated from wild emmer and was strongly domesticated in the current varieties. Therefore, TaHST1L involved in the auxin signalling pathway showed the big potential to improve wheat yield by controlling plant architecture. [ABSTRACT FROM AUTHOR]

Summary: The LRK10‐like receptor kinases (LRK10L‐RLKs) are ubiquitously present in higher plants, but knowledge of their expression and function is still limited. Here, we report expression and functional analysis of TtdLRK10L‐1, a typical LRK10L‐RLK in durum wheat (Triticum turgidum L. ssp. durum). The introns of TtdLRK10L‐1 contained multiple kinds of predicted cis‐elements. To investigate the potential effect of these cis‐elements on TtdLRK10L‐1 expression and function, two types of transgenic wheat lines were prepared, which expressed a GFP‐tagged TtdLRK10L‐1 protein (TtdLRK10L‐1:GFP) from the cDNA or genomic DNA (gDNA) sequence of TtdLRK10L‐1 under the native promoter. TtdLRK10L‐1:GFP expression was up‐regulated by the powdery mildew pathogen Blumeria graminis f. sp. tritici (Bgt) in both types of transgenic plants, with the scale of the elevation being much stronger in the gDNA lines. Both types of transgenic plants exhibited enhanced resistance to Bgt infection relative to wild type control. Notably, the Bgt defence activated in the gDNA lines was significantly stronger than that in the cDNA lines. Further analysis revealed that a putative MYB transcription factor binding site (MYB‐BS, CAGTTA) located in TtdLRK10L‐1 intron I was critical for the efficient expression and function of TtdLRK10L‐1 in Bgt defence. This MYB‐BS could also increase the activity of a superpromoter widely used in ectopic gene expression studies in plants. Together, our results deepen the understanding of the expression and functional characteristics of LRK10L‐RLKs. TtdLRK10L‐1 is likely useful for further dissecting the molecular processes underlying wheat defence against Bgt and for developing Bgt resistant wheat crops. [ABSTRACT FROM AUTHOR]

Summary: Development of marker‐free and transgene insertion site‐defined (MFTID) transgenic plants is essential for safe application of transgenic crops. However, MFTID plants have not been reported for wheat (Triticum aestivum). Here, we prepared a RNAi cassette for suppressing lipoxygenase (LOX) gene expression in wheat grains using a double right border T‐DNA vector. The resultant construct was introduced into wheat genome via Agrobacterium‐mediated transformation, with four homozygous marker‐free transgenic lines (namely GLRW‐1, ‐3, ‐5 and ‐8) developed. Aided by the newly published wheat genome sequence, the T‐DNA insertion sites in GLRW‐3 and GLRW‐8 were elucidated at base‐pair resolution. While the T‐DNA in GLRW‐3 inserted in an intergenic region, that of GLRW‐8 inactivated an endogenous gene, which was thus excluded from further analysis. Compared to wild ‐type (WT) control, GLRW‐1, ‐3 and ‐5 showed decreased LOX gene expression, lower LOX activity and less lipid peroxidation in the grains; they also exhibited significantly higher germination rates and better seedling growth after artificial ageing treatment. Interestingly, the three GLRW lines also had substantially increased contents of several fatty acids (e.g., linoleic acid and linolenic acid) in their grain and flour samples than WT control. Collectively, our data suggest that suppression of grain LOX activity can be employed to improve the storability and fatty acid content of wheat seeds and that the MFTID line GLRW‐3 is likely of commercial value. Our approach may also be useful for developing the MFTID transgenic lines of other crops with enhanced grain storability and fatty acid content. [ABSTRACT FROM AUTHOR]