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Many Cas9-derived base editors have been developed for precise C–to–T and A–to–G base editing in plants (Molla et al., 2021). They are typically based on a SpCas9 nickase or its engineered variants with altered protospacer adjacent motif (PAM) requirements (Molla et al., 2021). CRISPR–Cas12a enables highly efficient multiplexed genome editing in plants, and its T-rich PAM preference complements the G–rich PAM requirement of SpCas9 in genome targeting (Zhang et al., 2019, 2021). Because of the lack of an efficient Cas12a nickase, it has been challenging to develop efficient Cas12a base editors. Nevertheless, Cas12a cytosine base editors (CBEs) and adenine base editors (ABEs) have been developed in mammalian cells (Li et al., 2018; Kleinstiver et al., 2019) with low DNA damage (Wang et al., 2020) because deactivated Cas12a (dCas12a) was used. However, efficient dCas12a base editors are yet …