TaSnRK2.1-2D Contributes to Drought Tolerance by Modulating ROS Production in Wheat.

Drought stress is a major constraint to global agricultural productivity, particularly for wheat (Triticum aestivum L.), a staple crop critical for food security. Climate change has exacerbated the frequency and severity of drought events, causing significant yield losses (Berauer et al. 2024). Approximately 20 million hectares of wheat crops are routinely exposed to drought, underscoring the urgent need for drought-resilient varieties (Coughlan de Perez et al. 2023). Plants respond to drought through complex physiological and molecular mechanisms, including the regulation of reactive oxygen species (ROS) and the formation of aerenchyma-specialized tissues with intercellular air spaces that enhance oxygen diffusion and stress tolerance (Bhanbhro et al. 2020; Ali and Muday 2024). SnRK2s (Sucrose Non-fermenting 1-Related Protein Kinases) are involved in ABA responses and contribute to important agronomic traits, such as grain yield in crops and enhance the adaptation of horticultural crops to drought and other abiotic stresses, partially through the reduction in ROS levels (Zhang et al. 2022, 2023). However, their interaction with catalase, one of an important ROS-scavenging enzymes, remain incompletely characterized, representing a critical gap in plant stress response mechanisms. Here, we demonstrate that TaSnRK2.1-2D enhances drought tolerance and agronomic performance in wheat by promoting aerenchyma formation, and interacting with catalase (TaCAT-1A) to modulate ROS scavenging.