The Molecular Mechanisms Of Biological Nitrification Inhibitor Methyl 3-(4-hydroxyphenyl)Propionate Modulates Root Development In Arabidopsis

Methyl 3-(4-hydroxyphenyl) propionate(MHPP) is a root exudate that functions as a nitrification inhibitor which is discovered in recent years. Except to be a nitrification inhibitor, it can also be a modulator of the root system architecture(RSA)by inhibiting primary root(PR) elongation and promoting lateral root formation. And then accelerates the absorption of nutrients.However, the mechanism underlying MHPP-mediated modulation of the RSA remains unclear. In our research, we used physiology method, genetics method, pharmacology method, molecular biology method and so on, then we give the following results:1. We found that MHPP inhibits the length of Primary root through influences the division of Meristematic zone. Further more, MHPP induces an increase in auxin levels by up-regulating auxin biosynthesis, altering the expression of auxin carriers,and promoting the degradation of the auxin/indole-3-acetic acid family of transcriptional repressors. Finally causes the accumulation of auxin.2. We also found that MHPP-induced nitric oxide(NO) production promotes reactive oxygen species(ROS) accumulation in root tips. In addition, NO and ROS also influence the accumulation of auxin, and then inhibit the division of Meristematic zone and PR elongation.3. We also found that, MHPP not only induces the level of IAA, but also induces the level of SA and JA. It also accelerates the the expression level of the genes which related with the synthesis of glucosinolate. Come to a conclusion, except to be a nitrification inhibitor, it can also be a modulator of the root system architecture(RSA);it can also induces the ability of disease-resistant in plants by SA and JA.On the whole, our results indicate that MHPP modulates RSA remodeling via the NO/ROS-mediated auxin response pathway in Arabidopsis, then affect growth and development of plant finally.Our research reveals a new function of MHPP, and gives some theoretical basis to MHPP can increases the utilization efficiency of nitrogenous fertilizer, be a modulator of the root system architecture(RSA), accelerates the absorption of nutrients, and increases the ability of disease-resistant in plants.