Functional verification of LcSGRs by transient expression in N. benthamiana leaves and VIGS in litchi “YZZH.” A) The phenotype of N. benthamiana leaves transiently expressing PEAQ-LcSGRs, with the empty PEAQ vector as a control. B) SPAD values of N. benthamiana leaves transiently expressing PEAQ-LcSGRs. Bars above the columns represent standard error of mean. Double asterisks (**) indicate significant difference compared with the control at P < 0.01, Student's t-test (n = 6). C) Litchi fruit color phenotype after LcSGR silencing using pTRV2-vector. Images were digitally extracted for comparison. Bars = 1 cm. D) Changes of LcSGR expression, color parameters, chlorophyll contents, and anthocyanin contents in the pericarp in response to the silencing of LcSGR. Bars above columns represent standard error of mean. Double asterisks (**) indicate significant difference compared with the control at P < 0.01, Student's t-test (n = 12). E) Changes in pericarp chloroplast structure observed using a transmission electron microscope in response to LcSGR silencing. The red arrows denote chloroplasts. Bars = 1 μm. F) Changes in the expression of genes involved in chlorophyll degradation and anthocyanin biosynthesis in response to LcSGR silencing. Bars above columns represent standard error of mean. Single asterisks (*) and double asterisks (**) represent significance compared to the control at P < 0.05 and P < 0.01, respectively, Student's t-test (n = 3).