Prime Editing of OsGS1 Confers Glufosinate Tolerance in a Korean Rice Cultivar

Abstract

Weed control is among the principal challenges limiting the wider adoption of direct-seeded rice cultivation. Glufosinate is an effective non-selective herbicide, although its use in rice fields is limited by the high sensitivity of cultivated rice to this compound. However, a previously identified OsGS1;1 6-bp insertion allele (GCCTTC) has been established to confer glufosinate tolerance in rice, and in this study, using a dual-pegRNA prime editing strategy, we precisely introduced this allele into the Korean japonica rice cultivar Dongjin. Sanger sequencing of regenerated T0 plants identified the predicted homozygous 6-bp insertion in 14 of the 23 analyzed lines, corresponding to a homozygous precise editing frequency of 61%. Compared with the wild-type plants, when subjected to 2.5 mg/L glufosinate treatment, T2 plants derived from the homozygous line PE-gs1-1 were characterized by significantly greater shoot and root lengths, whereas only minor differences were observed in the absence of the herbicide. These findings reveal that the 6-bp OsGS1;1 insertion allele confers glufosinate tolerance in Dongjin following prime editing, thereby providing a transgene-free edited genetic resource for weed management and a strategy that is potentially applicable to other Korean rice cultivars.