Investigation About VA Fungus Species In Yang Ling Area In Wheat Rhizosphere And Study On The Effection Of VA Fungi On Phosphorus Absorption In Wheat Seedlings

Vesicular-arbuscular mycorrhizal fungi are widespread in the biosphere,It can form a symbiotic relationship with most plants.VAM fungi have positive effect on physiology and biochemistry,it can expand the roots absorbtion area,enhance the roots capacity to water,strengthen the phosphorus fixation,promote the conversion for nitrogen and improve the absorption of trace elements in soil.The distribution of VAM fungi depends on soil physical and chemical properties,hose specoes,altitude and physiological characteristics.On the oen hand,this study carried out the VAM fungi species investigation in Yang Ling area,and study of physiological characteristics of widely strains on the wheat roots;on the other hand, Statistic the roots infection on the field for six consecutice years.Hopefully can make practical reference for the improvement of biotechnology fertilizer and high-yield wheat.Main research results are as follow:1. The experiment separate 19 VAM fungi species of 4 genera, 12 in which belong to Glomus,4 belong to Acaulospora, 2 belong to Gigaspora and another 1 belong to Scutellospora;and there are still some uncertain species from the survey areas which needs to be identified.2.The VAM fungi distribution will take on different state.The comparative diversity is Glomus,Next to it is Acaulospora.3.The research found that the highest spore density was not always followed by largest number of VAM fungi species. Explain that there exist the competition and some complicated relationship among species; In addition, different types of fungal sporulation capacity are not the same.4.There is close relationship between spore density and soil factors. The more fertile soil have,the higher spore density exist,But it doesn't mean the species have large numbers.On the soil fertility level,Cui Xigou is the highest. The difference in adapt pH value can also cause the distribution differently.5.The research show that the distribution of G.mosseae and G.versiforme have the most relevant,speculating are the dominant species of local area. 6.G.mosseae and G.versiforme have positive effect on wheat seedlings.Under the different phosphorus concentration,The two fungi species have positive effect on wheats height,roots length,roots activity,water potential and soluble protein,especially at the 1μmol/L. Comparative the G.mosseae and G.versiforme,the former may has the better result.7. Compare the different growth stages,different N levels and planting patterns, We can conclude that wheat roots have the hightest infection rate in the filling stage. Infection are hightest at straw mode in filling stage of three nitrogen levels.It shows that wheat roots are infected by VA fungi mainly resolve to development stages and planting pattern.