| About 74% of agricultural soils (a total area of more than 7 million hectares) are reported deficiency with phosphorus due to the low availability of this major nutrient element. This will become a major limiting factor for agricultural production in China. Heavy inputs of chemical fertilizers and pesticides are necessary for increasing agricultural products. Such management practices are expensive and commonly aggravate the problem because they are source of pollution which further affects soil structure and activity. The objective of this study is to isolate AM fungal species from Hubei cultivated soil, screen efficient isolates for inoculation in agricultural practice, and develop molecular probes for monitoring of selected AM fungi in fields to ensure the persistence of effective inoculated isolates.34 AM fungal isolates were obtained by the procedures of trap culture, sieving and decanting or single spore isolating techniques. Large numbers of these isolates were the members of Glomus which were demonstrated widely distributed over the world. 15species was identified as new isolates in China and 17 species was registered in International Bank of Glomeromycota (IBG), Kent University Britain. After comparative screening by pot culture in glasshouse conditions, high efficient isolate HAU01 (Glomus constictum) was obtained. This AM fungus significantly improved maize growth in field experiments. 11.8% of maize seeds yield was increased compared with uninoculated control treatment. Starch content in seeds was parallel by 0.42% increased.Tolerant ability of plant to Cd pollusion was obviously improved by inoculation with Glomus intraradices, Glomus mossea, Gigaspora margarita separately or the mixture of these AM fungi. However, the sensitivity of these fungi to Cd concentration was different according to the species. High efficient AM fungus, Glomus mosseae, was found to accumulate even 80% of absorbed Cd in plant roots and its own mycelium, hence prevent this pollutant element be transferred up to plant tissue. This finding may possibly explain the mechanisms of the tolerance of mycorrhizal plant to polluted heavy metals for example Cd. It may also imply the potential of application of AM fungi for bioremediation of metal polluted soil. This study also demonstrated that the activity of succinate dehydrogenase and alkaline phosphatase was influenced by the presence of Cd, especially at high concentration level.Based on the analysis of highly variable region (D1-D2 domains) in 25s rDNA sequence AM fungal species-specific primers, XLD3-NDL22, XLO3-NDL22, XLA2-LR1,...
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