CRISPR/Cas9-mediated disruption of OsPLDβ1 enhances salt stress tolerance in rice through modulation of antioxidant defense

Abstract

Soil salinity is a critical abiotic stress that severely constrains rice productivity and threatens global food security. Phospholipase D (PLD) enzymes play pivotal roles in plant stress signaling; however, the specific function of OsPLDβ1 in rice salt stress responses remains unclear. We here investigated the role of OsPLDβ1 using knockout mutants to elucidate its regulatory function under saline conditions. Ospldβ1-mutant lines exhibited substantially improved salt tolerance in contrast to wild-type plants. Improved tolerance was associated with elevated reactive oxygen species (ROS) scavenging capacity, indicating improved oxidative stress management. Furthermore, the mutant lines displayed increased expression of ion transport and homeostasis genes and maintained photosynthetic efficiency and agronomic performance. Collectively, these physiological and molecular responses demonstrate that OsPLDβ1 negatively regulates salt stress tolerance in rice. This research highlights the role of OsPLDβ1 in salt tolerance in rice and lays the groundwork for developing salinity-resistant crop varieties through genetic manipulation.