Enhancement of asparagus seedling growth through arbuscular mycorrhizal fungus inoculation

The effect of the inoculation density of arbuscular mycorrhizal (AM) fungal [Glomus etunicatum (GE) and Gigaspora margarita (GM)] spores on AM fungus infection and growth of asparagus seedlings was investigated. Three months after inoculation, plant height was large in seedlings inoculated with 1000 or 3000 GE spores, and those inoculated with 20, 100 or 500 GM spores. The rate of AM fungus-infected portions in a whole root system reached a maximum of 55.2% in treatment inoculated with 1000 GE spores and 52.3% in that inoculated with 100 GM spores. The optimum inoculation density of AM fungal spores needed to maximize both AM fungus infection and plant growth promotion through symbiosis varied with AM fungus species.