Virus-mediated, heritable gene editing in groundcherry (Physalis grisea)

Introduction: Virus-induced gene editing (VIGE) provides a powerful alternative to conventional plant genome engineering by enabling in planta delivery of genome-editing reagents without repeated use of tissue culture. Here, we establish Tobacco rattle virus (TRV)–mediated VIGE as an efficient system for somatic and heritable genome editing in groundcherry (Physalis grisea).

Methods: Using Cas9-expressing plants, we targeted the visual marker gene PHYTOENE DESATURASE (PDS) and the domestication gene CLAVATA1 (CLV1) via TRV-mediated delivery of guide RNAs. Editing efficiencies were evaluated in somatic tissues and across progeny to assess heritability.

Results: Targeting of PDS resulted in somatic editing frequencies of 80–95% and consistent recovery of heritable edits, with all infected plants (n = 5) producing edited progeny, including fully albino seedlings carrying frameshift mutations in all alleles. The primary Cas9-expressing line was unexpectedly tetraploid, likely due to genome duplication during tissue culture. Despite this, VIGE efficiently generated mono-, bi-, tri-, and tetra-allelic mutations, demonstrating robust editing across four alleles simultaneously. Targeting of CLV1 achieved somatic editing frequencies of up to 73%, with 60% of T0 plants producing heritable edits. Edited plants exhibited increased floral organ number and multilocular fruits, consistent with CLV1 loss-of-function phenotypes.

Conclusion: These results demonstrate that VIGE enables rapid, efficient, and heritable genome editing in groundcherry, even in a tetraploid context, highlighting its potential to accelerate genetic improvement and de novo domestication of underutilized crops.