Efficiency of VAM hyphae in utilisation of organic phosphorus by wheat plants

TLDR: The depletion oforganic P depended on the soil type, hyphal length density, phosphatase activities and the amount of organic P present in the system, which caused depletion of V A-mycorrhizal hyphae throughout the hyphal compartment.

Abstract: In a pot experiment wheat (Triticum aestivum L.) was grown under axenic conditions in two soils differing in organic matter and phosphorus contents. The pots were separated by 30 .urn nylon nets and a 0.45 .urn membrane into five compartments, a central one for root growth, two adjacent to the central compartment for hyphal growth and two outer ones for control. The treatments consisted of sterilized soil, supply of organic (Na-phytate) or inorganic phosphorus (P) and of soil either non-inoculated or inoculated with Glomus mosseae. Shoot dry weight increased by mycorrhizal inoculation in the range between 2.2 and 4.5 g pot−1 depending on the soil and treatment. Organic P was depleted by V A-mycorrhizal hyphae throughout the hyphal compartment (15 mm). The maximum depletion was 106 mg kg−1 soil within a 0.5 mm distance from the root surface. The depletion of organic P depended on the soil type, hyphal length density, phosphatase activities and the amount of organic P present in the system. The max...