Influence of Selected Vesicular-arbuscular Mycorrhizal Fungi on Seedling Growth and Phosphorus Uptake of Sophora secundiflora1

Abstract

Seedlings of Sophora secundiflora (Ortega) Lag. were grown in 10.2-cm diameter pots containing sterilized media individually inoculated with 1 of 4 vesicular-arbuscular (VA) mycorrhizal fungi and fertilized with Omocote (18N-6P-12K) at rates of 0, 1.2, or 4.2 kg/m 3 . After 263 days, seedlings inoculated with Glomus mosseae (Nicol. and Gerd.) Gerd. and Trappe and with Gigaspora margarita Becker and Hall exhibited increased fresh and dry weights of shoots and roots and root quality at the 1.2 kg/m 3 fertilizer level. Increased growth responses of seedlings inoculated with either G. mosseae or G. margarita at 1.2 kg/m 3 Osmocote were comparable to noninoculated controls at 4.2 kg/m 3 . G. etunicatus Becker & Gerd. and G. fasciculatus (Thaxt. sensu Gerd.) Gerd. & Trappe did not enhance seedling growth at any fertilizer rate tested, nor were they colonized on seedling roots. Microscopic examination of roots confirmed VA mycorrhizal colonization at all 3 fertilizer levels with G. mosseae , and at the 2 lowest levels with G. margarita . Increased P uptake occurred only with G. mosseae- inoculated seedlings at 0 and 1.2 kg/m 3 fertilization rates.