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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]

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: Gliadins are a major component of wheat seed proteins. However, the complex homoeologous Gli‐2 loci (Gli‐A2, ‐B2 and ‐D2) that encode the α‐gliadins in commercial wheat are still poorly understood. Here we analyzed the Gli‐D2 locus of Xiaoyan 81 (Xy81), a winter wheat cultivar. A total of 421.091 kb of the Gli‐D2 sequence was assembled from sequencing multiple bacterial artificial clones, and 10 α‐gliadin genes were annotated. Comparative genomic analysis showed that Xy81 carried only eight of the α‐gliadin genes of the D genome donor Aegilops tauschii, with two of them each experiencing a tandem duplication. A mutant line lacking Gli‐D2 (DLGliD2) consistently exhibited better breadmaking quality and dough functionalities than its progenitor Xy81, but without penalties in other agronomic traits. It also had an elevated lysine content in the grains. Transcriptome analysis verified the lack of Gli‐D2 α‐gliadin gene expression in DLGliD2. Furthermore, the transcript and protein levels of protein disulfide isomerase were both upregulated in DLGliD2 grains. Consistent with this finding, DLGliD2 had increased disulfide content in the flour. Our work sheds light on the structure and function of Gli‐D2 in commercial wheat, and suggests that the removal of Gli‐D2 and the gliadins specified by it is likely to be useful for simultaneously enhancing the end‐use and health‐related traits of common wheat. Because gliadins and homologous proteins are widely present in grass species, the strategy and information reported here may be broadly useful for improving the quality traits of diverse cereal crops. [ABSTRACT FROM AUTHOR]

Although most known viruses infecting fungi pathogenic to higher eukaryotes are asymptomatic or reduce the virulence of their host fungi, those that confer hypervirulence to entomopathogenic fungus still need to be explored. Here, we identified and studied a novel mycovirus in Metarhizium flavoviride , isolated from small brown planthopper ( Laodelphax striatellus ). Based on molecular analysis, we tentatively designated the mycovirus as Metarhizium flavoviride partitivirus 1 (MfPV1), a species in genus Gammapartitivirus , family Partitiviridae . MfPV1 has two double-stranded RNAs as its genome, 1,775 and 1,575 bp in size respectively, encapsidated in isometric particles. When we transfected commercial strains of Metarhizium anisopliae and Metarhizium pingshaense with MfPV1, conidiation was significantly enhanced ( t test; P -value < 0. 01), and the significantly higher mortality rates of the larvae of diamondback moth ( Plutella xylostella ) and fall armyworm ( Spodoptera frugiperda ), two important lepidopteran pests were found in virus-transfected strains (ANOVA; P -value < 0.05). Transcriptomic analysis showed that transcript levels of pathogenesis-related genes in MfPV1-infected M. anisopliae were obviously altered, suggesting increased production of metarhizium adhesin-like protein, hydrolyzed protein, and destruxin synthetase. Further studies are required to elucidate the mechanism whereby MfPV1 enhances the expression of pathogenesis-related genes and virulence of Metarhizium to lepidopteran pests. This study presents experimental evidence that the transfection of other entomopathogenic fungal species with a mycovirus can confer significant hypervirulence and provides a good example that mycoviruses could be used as a synergistic agent to enhance the biocontrol activity of entomopathogenic fungi., Competing Interests: Competing interests statement:The authors declare no competing interest.

Currently methods for generating soybean edited lines are time-consuming, inefficient, and limited to certain genotypes. Here we describe a fast and highly efficient genome editing method based on CRISPR-Cas12a nuclease system in soybean. The method uses Agrobacterium-mediated transformation to deliver editing constructs and uses aadA or ALS genes as selectable marker. It only takes about 45 days to obtain greenhouse-ready edited plants at higher than 30% transformation efficiency and 50% editing rate. The method is applicable to other selectable markers including EPSPS and has low transgene chimera rate. The method is also genotype-flexible and has been applied to genome editing of several elite soybean varieties., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)