Correction to: Overexpression of PtPEPCK1 gene promotes nitrogen metabolism in poplar

Correction to: J. For. Res. https://doi.org/10.1007/s11676-019-01042-4

In the Original publication, the author has found that C1 and C4 in Fig. 3 have been published with errors. The corrected Fig. 3C1 and C4 are provided below.

Fig. 3

Regeneration of Agrobacterium-mediated transformed Populus by the dark-induced and light-induced methods; A1 co-cultivation of leaf discs with Agrobacterium on MS medium in the dark; A2–B2 callus induction in 84 K poplar from leaves cultured on MS medium treated with various concentrations and combinations of 2,4-D, KT, and TDZ hormones after 8–10 weeks at 25 ± 2 °C under dark conditions; B3–B4 shoot regeneration from well-developed callus from different media; B3 elongated shoots from clusters which had attained 2–3 cm in length; B4 elongation period: transgenic plantlets forming roots within 2 weeks in kanamycin-containing rooting medium and acclimatization period; C1 and C2 co-cultivation of leaf discs with Agrobacterium on MS medium in light and leaf explants cultured on selected media with 50 mg·L^− 1 kanamycin and 300 mg·L ^− 1 cefotaxime for 3–4 weeks after co-cultivation; C3 regenerated transformants on MS medium; C4 regenerated transformants on MS medium generated with the optimization of transformation efficiency; kana-resistant shoots were further elongated in the medium and buds started appearing in clusters; D1–D2 regeneration of plantlets in MS medium; D3 transgenic plantlets forming roots within 2 weeks in rooting medium containing kanamycin; D4 acclimatization period