Relative effect of vesicular arbuscular mycorrhizal fungi on growth and nutrient uptake of Casuarina equisetifolia

摘要

The importance of mycorrhizae to trees and shrubs as well as Frahkia nodules to actinorhizal shrubs and trees would be greatest on planting site where nutrient and other stresses are extreme. Vesicular Arbuscular Mycorrhizal fungi (VAM) are beneficial symbiotic microorganisms that colonize the root and increase the growth and yield of several crop plants. The improved growth is attributed to increased nutrient uptake, growth hormone production and greater ability to withstand water stress and theirbeneficial interactions with other soil microorganisms. Several workers have reported the increased plant growth by VAM fungal inoculation on legumes, field crops and horticultural crops. The studies are only few on non-leguminous trees like Casuarina (Vasanthakrishna and Bagyaraj, 1991). More over this root fungus represents one of the nature's best gift to mankind in conversion of soil to fertile and productive soil (Mukerji and Dixon, 1992). Mostly the Casuarina like trees are mainly grown in nutrient poor environments and the fungi may offer greater benefit for the establishment of the trees. Hence, the present investigation was carried out with the view to identity the efficient VAM fungi to derive maximum benefit in terms of enhanced nodulation,growth and nutrient status.