TRV-mediated VIGS of the CsPOR1 gene in tea-cutting leaves. (A) Untreated tea cuttings. (B) New leaves with normal symptoms 20 d after infection with pTRV1 + pTRV2. (C) New leaves with albino symptoms 20 d after infection with pTRV1 + pTRV2-CsPOR1. (D) Expression of CsPOR1 was downregulated in the leaves of tea cuttings that were albino or reddish. WT, uninfected cuttings; pTRV2, infection with pTRV1 + pTRV2 Agrobacterium; pTRV2-CsPOR1-albino and pTRV2-CsPOR1-reddish, infection with pTRV1 + pTRV2-CsPOR1 Agrobacterium. The error bars represent the mean ± SE of the three independent experiments. Different lowercase letters indicate significant differences at p < 0.05 by Duncan’s multiple range test. qRT-PCR, real-time quantitative reverse transcription PCR; SE, standard error; TRV, tobacco rattle virus; VIGS, virus-induced gene silencing.