Arbuscular Mycorrhizal Status and Influence of Artificial Inoculations on Growth of Nursery Seedlings of Four Agroforestry Tree Species

Abstract

Investigations on mycorrhizal status of seedlings of four agroforestry tree species viz., Acacia nilotica, Albizia lebbeck, Pongamia pinnata and Sesbania grandiflora grown in six social forestry nurseries in terms of percentage of colonization, number of resting spores in rhizosphere and presence of arbuscules, vesicles and mycelium in the colonized roots was determined. Percentage of colonization, spore population and nodulation of seedlings varied with the tree species as well as soil. All the three characteristic structures of AM fungi viz., internal mycelium, vesicles and arbuscules were observed inside the roots. A set of six AM fungi representing four genera viz., Glommus fasciculatum, Gl. macrocarpum, Gl. dussi, Acaulospora delicate, Gigaspora sp. and Scutellospora sp. were evaluated under pot culture conditions to select an efficient strain. All these strains supported good growth of saplings compared to uninoculated control. G. fasciculatum was selected for further investigations in view of its superior support of growth of seedlings.