Study On Effects Of Nitrogen And Phosphorus Compling On Argintine Translocation And Nitrogen Levels In The Complete System Of Plants

Arbuscular mycorrhizal fungi (AM fungi,AMF) with most land plants form a symbiotic relationship. ERM(Extraradical Mycelium), the root of external hyphae body (Extraradical up) will assimilate different forms of nitrogen(N) and phosphorus(P) Sources of the surroundings, respectively synthesizing arginine (Arg) and poly phosphate which supply the use of plants. Meanwhile, using the supply of carbohydrates in plants fungi complete their life cycle. It is essential that the N and P sources availability and mobility for arbuscular mycorrhizal fungi and plant nutrition, and Arginine is not only the main nutrition storage form of AM fungi, but also is N vectors of translocation and transmission from the AM fungal hyphae to the host. Therefore, this experiment detecting the absorption, translocation and expression of arginase in the rhizo-box by inoculation with AM fungi at the seedling stage of sorghum and form sorghum AM symbiont, is conducted to study on effects of nitrogen and phosphorus compling on arginine translocation and nitrogen levels in the complete system of plants.This experiment using Sorghum(Sorghum bicolor L. Moench) as the host whose roots are inoculated with glomus(Rhizophagus irregularis) and the river sand and marl as a matrix in the culture box, explores the optimum nitrogen and phosphorus concentration of the symbiont under the conditions of different concentration of N and P. Using urea as nitrogen source, KH2PO4 as P source, the experiment designs five concentration gradient and explores optimal N, P concentration of the symbiont of AM fungi and sorghum. The experimental data shows that the most suitable infectious N and P concentration of R.irregularis and seedling sorghum is N2P1 (8mmol/L, O.Olmmol/L), indicating that high concentrations of nitrogen and low concentration of P contribute to the infection of R.irregularis hyphae and seedling sorghum. At the same time, in the inoculation AM fungi can shorten the time of establishing the symbiotic relationship between AM fungi and sorghum.The experiment with the sorghum as host plants, adding the same concentration of different nitrogen sources to mycelium compartment, researches the relative expression of the arginase in IRM and the content of aboveground nitrogen and phosphorus of plants. The results show that urea as N source, total nitrogen content was the highest for 16.0137g/kg, total phosphorus content was the highest for 0.6080g/kg, root hyphae arginase expression level was the highest for 1.7569, on that condition, it is conducive to accumulation and translocation of N and P in the sorghum, and AM fungi absorbs nitrogen and phosphorus which lie in interaction phenomena.This study is to explore the effects of different concentration combination of nitrogen and phosphorus on R.irregularis and the effects of the expression levels of key enzymes in the process of decomposition of Arg. Results show that Arg as N source is more conducive to the accumulation of aboveground biomass of sorghum than urea; the same N source, P source for KH2PO4, plant aboveground biomass is highest for 0.9066g, phosphorus content was the highest for 1.0415g/kg, and arginine content was the highest for 0.0768g/kg, which indicates that KH2PO4 is conducive to arginine transplocation of AM fungi and phosphorus absorption and accumulation of the host. The same nitrogen source, calcium superphosphate as P source, arginase mRNA expression level of IRM reached the highest for 15.9101, showing that the conditions are favorable for the arginine translocation in mycorrhizal.This experiment with Sorghum(Sorghum bicolor L.Moench) as the host whose roots is inoculated with glomus(Rhizophagus irregularis),using Maotai lees fertilizer and ordinary organic manure as fertilizers which are differently treated applying to the hyphal compartments, while adding "Gu Lin" microbial Rot stalk agent, to explore the effects of different treatments of organic fertilizer and AM fungi on the growth of sorghum. Results show that the hyphae compartment adds lees + Rot stalk agent (sterilization), chlorophyll content of sorghum reaches the highest for3.804mg/g and total phosphorus content in the upper reaches 0.7310g/kg, showing that the conditions are favorable for photosynthesis of plants and phosphorus accumulation of sorghum. Hyphal compartment adds lees + organic fertilizer + Rot stalk agent (non-sterile), dry weight of aboveground sorghum reached the highest for 3.3807g, cultivating the sorghum for 80 days, its height reached a highest for 80.8cm, total nitrogen content of stem leaf in the highest reaches 25.9496g/kg; showing the condition is most conducive to the accumulation of sorghum growth and biomass and total nitrogen content. These results above indicated that the mycelia compartments adding different treatment lees fertilizer is more conducive to the growth of sorghum.