Vesicular-arbuscular Mycorrhizal Fungus' Effects On Physiological Ecology Of Broussonetia Papyrifera Population Growing In Limestone Habitat

The problem of desertification is attracting more attentions today. Soil severely erodes, bedrock appears massively, and productivity decreases in limestone districts, which are all caused by human's unreasonable social economic activity. It is becoming urgent to carry out ecological restoration in limestone desertification districts.There are two approaches for ecological restoration, biological and non-biological. This paper is mainly on the experiment of Broussonetia papyrifera's inoculation with biological factor of mycorrhizal fungi on the ground of lime, to solve the problem of desertification and restore the ecosystem. Broussonetia papyrifera is given single inoculation, co-inoculation, and non-inoculation with three species of vesicular- arbuscular (VA) mycorrhizal fungus, including Glomus.mosseea, Glomus.versiforme, and Glomus. diaphanum. In three months, some targets of growth, physiology and photosynthesis are measured in this experiment. The results follow:Broussonetia papyrifera seedlings can increase the absorption of nitrogen and phosphorus through inoculation with VA mycorrhizal fungi. The nitrogen concentration enhances significantly in the roots, stems and leaves of the Broussonetia papyrifera seedlings, but the enhancement of the phosphorus concentration is not significant in the leaves except in the roots and stems of the host plant seedlings. At the same time, the concentration of chlorophyl a and b increase significantly in the leaves of Broussonetia papyrifera seedlings. It induced that the net photosynthesis rate boosts up compared with the controlled non-inoculation. Because of the accumulation of nutrition and the enhancement of photosynthesis capacity, the inoculated seedlings increase in height, diameter, area of total leaves, and the trunk weight above ground and below ground compared with the controlled groups. The promotion effects of biomass in co-inoculation are better than single inoculation, while Glomus diaphanum has best effects in the single...