Table 1 Description of each treatment in this study

15S

P-free NS

400 g of substrate + 2 g of Ca₃(PO₄)₂

Inoculation by pipetting 1 ml of bacterial biostimulant Enterobacter sp. 15S (10⁸ cells ml⁻¹) onto the seedlings at the rooting site

Ci

P-free NS supplemented with 1 mM citric acid

400 g of substrate + 2 g of Ca₃(PO₄)₂

Fu

P-free NS supplemented with 1 mM fumaric acid

Ke

P-free NS supplemented with 12 mM α-ketoglutaric acid

Ma

P-free NS supplemented with 7 mM malic acid

Ox

P-free NS supplemented with 2 mM oxalic acid

Mix

P-free NS supplemented with 1 mM citric acid + 1 mM fumaric acid + 12 mM α-ketoglutaric acid + 7 mM malic acid + 2 mM oxalic acid

Control P-

P-free NS

Control P + 

P-full NS (KH₂PO₄ 0.1% P w/v)

400 g of substrate