Proteins with a tandem kinase structure have recently emerged as new players in race-specific resistance in cereal crops. However, the molecular understanding of these novel immune receptors’ resistance mechanisms is limited by the lack of knowledge about the pathogen effectors that they recognise. In this work, we identify AvrWTK4, the wheat powdery mildew RNase-like effector recognised by the wheat tandem kinase immune receptor WTK4, through a combination of bi-parental genetic mapping and mutagenesis. We demonstrate that mutations in the AvrWTK4 gene or a reduction of its expression lead to virulence on WTK4 . Transfection of AvrWTK4 specifically induced cell death in WTK4 -containing Aegilops tauschii protoplasts. The avirulent AvrWTK4 variant interacts more strongly than the virulent variant with the N-terminal heavy metal-associated (HMA)-like domain of WTK4. These findings further highlight that integrated domains in tandem kinase proteins serve as decoys for pathogen effectors, which could be leveraged to design novel recognition specificities.

Proteins with a tandem kinase structure have recently emerged as players in race-specific resistance in cereal crops. However, the molecular understanding of these immune receptors’ resistance mechanisms is limited by the lack of knowledge about the pathogen effectors that they recognise. In this work, we identify AvrWTK4, the wheat powdery mildew RNase-like effector recognised by the wheat tandem kinase protein WTK4, through a combination of bi-parental genetic mapping and mutagenesis. We demonstrate that mutations in the AvrWTK4 gene or a reduction of its expression lead to virulence on WTK4 . Transfection of AvrWTK4 specifically induced cell death in WTK4 -expressing Aegilops tauschii protoplasts. The avirulent AvrWTK4 variant interacts more strongly than the virulent variant with the N-terminal heavy metal-associated (HMA)-like domain of WTK4. We found that the integrated HMA-like domain possibly serves as a direct effector-binding decoy for WTK4, providing a mechanistic paradigm for effector recognition by tandem kinase proteins.

The sterile insect technique (SIT) is considered a promising and environmentally sustainable tool for controlling Aedes albopictus. While current guidelines address its implementation in moderately large and partially isolated areas, evidence from small, fully urban and spatially connected environments remains limited. In 2025, we evaluated SIT in two municipalities in southern Switzerland, releasing sterile males in small (≈12 ha), non-isolated urban areas representing contrasting operational contexts within ongoing integrated vector management programs. Entomological responses were assessed using a spatial, distance-based framework integrating ovitrap-derived egg abundance and hatching rates from treated and surrounding zones, alongside adult female monitoring. Following releases, egg abundance declined within treated areas relative to surrounding zones, with model-based peak reductions of approximately 57% in Ascona and 67% in Losone. Egg hatching rates were also lower within treated areas, with estimated reductions of approximately 9% and 22%, respectively. For both indicators, spatial analyses revealed gradual distance-dependent patterns rather than abrupt boundary effects. No consistent pattern was detected for adult female abundance, likely reflecting limited sampling intensity. The spatial and temporal responses observed across the two study sites suggest that SIT may contribute to modifying local reproductive dynamics of Ae. albopictus even in small, non-isolated urban areas under operational conditions.