Interactions Between Soil Moisture Content and Phosphorus Supply in Spring Wheat Plants Grown in Pot Culture

A pot culture experiment was carried out in a glasshouse to investigate the interactions between soil moisture content and phosphorus (P) supply in spring wheat (Triticum aestivum cv. Krichauff). Increases in soil moisture content and P supply significantly increased plant biomass production. Plant P uptake was also significantly enhanced by increases in soil moisture content and P supply. With no P addition, plant P uptake increased from 1.12 mg pot−1 to 3.25 mg pot−1 when soil moisture content was increased from 30% of water holding capacity (WHC) to 75% of WHC. The magnitude of the increase in P uptake in response to the increase in soil moisture content was smaller when extra P was added than with no P addition. Responses of plant biomass production and P uptake to P application were relatively greater in treatments with lower soil moisture content. Results also showed that increase in P supply might increase water use efficiency of wheat plants.