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Summary Plants have evolved a sophisticated immunity system for specific detection of pathogens and rapid induction of measured defences. Over‐ or constitutive activation of defences would negatively affect plant growth and development. Hence, the plant immune system is under tight positive and negative regulation. MAP kinase phosphatase1 (MKP1) has been identified as a negative regulator of plant immunity in model plantArabidopsis. However, the molecular mechanisms by which MKP1 regulates immune signalling in wheat (Triticum aestivum) are poorly understood. In this study, we investigated the role of TaMKP1 in wheat defence against two devastating fungal pathogens and determined its subcellular localization. We demonstrated that knock‐down ofTaMKP1by CRISPR/Cas9 in wheat resulted in enhanced resistance to rust caused byPuccinia striiformisf. sp.tritici(Pst) and powdery mildew caused byBlumeria graminisf. sp.tritici(Bgt), indicating thatTaMKP1negatively regulates disease resistance in wheat. Unexpectedly, whileTamkp1mutant plants showed increased resistance to the two tested fungal pathogens they also had higher yield compared with wild‐type control plants without infection. Our results suggested that TaMKP1 interacts directly with dephosphorylated and activated TaMPK3/4/6, and TaMPK4 interacts directly with TaPAL. Taken together, we demonstrated TaMKP1 exert negative modulating roles in the activation of TaMPK3/4/6, which are required for MAPK‐mediated defence signalling. This facilitates our understanding of the important roles of MAP kinase phosphatases and MAPK cascades in plant immunity and production, and provides germplasm resources for breeding for high resistance and high yield.
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Identifying novel sources of resistance to wheat stem sawfly in five wild wheat species
Abstract BACKGROUNDThe wheat stem sawfly (WSS,Cephus cinctus) is a major pest of wheat (Triticum aestivum) and can cause significant yield losses. WSS damage results from stem boring and/or cutting, leading to the lodging of wheat plants. Although solid‐stem wheat genotypes can effectively reduce larval survival, they may have lower yields than hollow‐stem genotypes and show inconsistent solidness expression. Because of limited resistance sources to WSS, evaluating diverse wheat germplasm for novel resistance genes is crucial. We evaluated 91 accessions across five wild wheat species (Triticum monococcum,T. urartu,T. turgidum,T. timopheevii, andAegilops tauschii) and common wheat cultivars (T. aestivum) for antixenosis (host selection) and antibiosis (host suitability) to WSS. Host selection was measured as the number of eggs after adult oviposition, and host suitability was determined by examining the presence or absence of larval infestation within the stem. The plants were grown in the greenhouse and brought to the field for WSS infestation. In addition, a phylogenetic analysis was performed to determine the relationship between the WSS traits and phylogenetic clustering. RESULTSOverall,Ae. tauschii,T. turgidumandT. urartuhad lower egg counts and larval infestation thanT. monococcum, andT. timopheevii.T. monococcum,T. timopheevii,T. turgidum, andT. urartuhad lower larval weights compared withT. aestivum. CONCLUSIONThis study shows that wild relatives of wheat could be a valuable source of alleles for enhancing resistance to WSS and identifies specific germplasm resources that may be useful for breeding. © 2024 The Authors.Pest Management Sciencepublished by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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- Award ID(s):
- 1822162
- PAR ID:
- 10518147
- Publisher / Repository:
- Wiley Online Library
- Date Published:
- Journal Name:
- Pest Management Science
- Volume:
- 80
- Issue:
- 6
- ISSN:
- 1526-498X
- Page Range / eLocation ID:
- 2976 to 2990
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/ps.8008
