Phloem-specific AVP1 silencing in AVP1-1 plants. A, Expression cassette with the phloem-specific promoter pCoYMV driving the expression of RNAiAVP1. B, AVP1-1 and pCoYMV::RNAiAVP1 T2 lines (1–3) grown in the absence of Suc for 30 d under a 12-h/12-h day-night regimen. Zoomed images of T2 lines as indicated. C, Immunohistochemical analysis of AVP1 in representative AVP1-1 (5 d old; n = 10 seedlings) and pCoYMV::RNAiAVP1 T2 lines 1 to 3 (15 d old; n = 6–10 seedlings from five independent pCoYMV::RNAiAVP1 lines). Note that all plants in C are at similar developmental stage (i.e. first true leaves emerging). LP, Leaf primordia; Ph, phloem. Black bars = 0.01 mm.