Fig. 7.

BnPHT1;4 is involved in phosphorus mobilization in cotyledons and phosphorus uptake in roots of Brassica napus. (a and b) Dynamics of the relative pool sizes of the total phosphorus (P) in oilseed rape seedlings of the BnPHT1;4 overexpression transgenic lines and controls (WT and CK). Seedlings grew on 1/2 MS medium with 1 mM Pi (a) or without Pi (b). P content was determined separately in cotyledons (c) and in roots plus leaves and hypocotyls (NC), and depicted as percentage of total P content in the whole seedling. The data are presented as means ± SD (n = 3). (c and d) Phosphate (Pi) contents in shoots and roots of seven-day-old seedlings of the BnPHT1;4 overexpression transgenic lines and controls grown under 1 mM Pi (c) and 20 μM Pi (d) conditions. KCl was used to replace KH₂PO₄ in the medium for the equivalent amount of potassium. The error bars indicate the standard errors. Significance of difference was analyzed by Duncan’s test (*p<0.05, **p<0.01, n = 9). WT, wild type; CK, transgenic null line; S5, S9, S10 and S11, independent BnPHT1;4 overexpression transgenic lines. DAG, day after germination