P uptake by plant H PO concentration in the root and Xylem sap is 100-1000 times greater than in the soil solution Active uptake is used to overcome this concentration gradient It is likely that inorganic P is co-transported across the plasma membrane with positively charged ions(Hf) The transport across the membrane requires energy. Wet or cold soils that reduce plant metabolic activity are likely to reduce P uptakeP uptake by plant H2PO4 - concentration in the root and xylem sap is 100-1000 times greater than in the soil solution Active uptake is used to overcome this concentration gradient. • It is likely that inorganic P is co-transported across the plasma membrane with positively charged ions (H+ ) • The transport across the membrane requires energy. Wet or cold soils that reduce plant metabolic activity are likely to reduce P uptake