Effect of vesicular–arbuscular mycorrhizal fungi and phosphorus on the survival and growth of flowering dogwood (Cornus florida)

Abstract

Mycorrhizal development and growth of flowering dogwood (Cornus florida L.) seedlings were investigated in a field nursery and glasshouse. Seedlings and associated soil were collected from April to November from a fumigated nursery bed that contained areas of both stunted and rapidly growing plants. The rate of mycorrhizal colonization and associated spore formation were greater on the rapidly growing seedlings. In a glasshouse test, dogwood seedlings were inoculated with chlamydospores of Glomus etunicatum, G. intraradices, or a control solution which contained microorganisms associated with the mycorrhizal fungi, and were fertilized weekly with Hoagland's solutions which had 0, 47, or 93 mg P∙L⁻¹. After 12 weeks, seedlings inoculated with G. etunicatum had greater survival, shoot dry mass, and root fresh mass than seedlings inoculated with G. intraradices or the control. However, G. etunicatum did not affect the concentration or total uptake of P into shoots. This fungus can apparently enhance the survival and growth of dogwood seedlings without improving P nutrition.