Enhancement of Growth and Phosphorous Concentrations in Apple Seedlings by Vesicular-arbuscular Mycorrhizae1

Abstract

Abstract Glomus mosseae (Nicol & Gerd.) Gerd. & Trappe, inoculation increased apple ( Malus domestica Borkh.) seedling growth in 3 of 5 fumigated orchard soils without supplemental phosphorous. Mycorrhizae improved seedling growth in only one soil receiving additional P. Increasing P rates up to 100–200 mg/kg improved growth in only one soil receiving additional P. Increasing P rates up to 100–200 mg/kg improved growth of nonmycorrhizal-treated apple seedlings in 4 of 5 soils tested. The 5th soil had an adequate P content, 60 mg/kg soil prior to the addition of P. Mycorrhizal root infection of seedlings growing in soil that received G. mosseae inoculum decreased with increased P rates applied. Some infection was found in seedlings from all soils inoculated with mycorrhizae at P rates of 0–400 mg/kg, and seedlings from 2 of the mycorrhizal soils had infection at the P rate of 600 mg/kg.