Molecular Mechanism Of Phosphorus Uptake By The Interaction Of Arbuscular Mycorrhizal Fungi And Maize

Phosphorus is one of the most important nutrient elements necessary for plant growth and development.The uptake and assimilation of phosphorus in crops affect directly their yield.However,as a considerable part of the phosphorus in the soil is in the form that plants can not absorb,usually the effective phosphorus content does not meet the needs of the plants.So the plants have evolved a series of adaptation mechanisms including arbuscular mycorrhizal fungi(Arbuscular mycorrhizal fungi,AMF)symbiosis in the long process of evolution to enhance the absorption,transport and reuse of phosphorus.Previous results showed that the formation of AM was beneficial to the absorption of inorganic phosphate(Pi)by host plants,and the high affinity Pi transporter genes played an important role in the process of plant utilization of soil Pi.However,the mechanisms that the interaction of AMF and maize promotes the uptake of Pi are still unclear.Two major gene families in maize have been found to be involved in Pi uptake: one is the high affinity Pi transport gene family ZmPHT1,which consists of 13 members,and the second is the low affinity Pi transport gene family ZmPHT2 with only one member.In this study,maize B73 was used to detect the effects of Pi starvation on the gene expression of PHT1 and PHT2 genes.This may provide a clue about the genes that play an important role in the environment of Pi deficiency.We detected the Pi content and total phosphorus content in different organs in maize at Male tetrad and Grouting stages by using the maize inbred lines with the AMF infection rate of 80% or more.The results showed increased contents of Pi and total phosphorus in AMF affected maize,indicating that AMF promotes the absorption and utilization of Pi in maize.The roots,stems,leaves of two stages were collected to detect the expression of PHT1 and PHT2 family genes.The results showed that the increase of inorganic phosphorus content was not only related to PHT1.4,PHT1.6,PHT1.8,PHT1.10,but also with PHT1.2,PHT1.8 and other phosphorus starvation-induced genes.Taken together,this study further enriched and developed the molecular mechanism of phosphorus uptake by the interaction of AMF and Maize,which provided the theoretical basis and guidance for the genetic breeding of maize and the development of sustainable agriculture.