Abstract: Endogenous bacterium Serratia marcescens XJU-PA-6 isolated from Paeonia anomala (grown in Tarbarha Taishan,Xinjiang),which can produce haematochrom,was used in this work.Firstly,haematochrom was isolated from the broth of XJU-PA-6 using fermentation method.And then the antagonistic effect of isolated haematochrom against 11 common crop pathogenic fungi was explored with agar plate diffusion method.The results showed that haematochrom produced by  S.marcescens XJU-PA-6 can strongly against Fusarium oxysporum f.Sp, Alternaria mali, Botrytis cinerea, Sclerotinia sclerotiorum, Verticillium dahliae and Fusarium oxysporum f. sp. niveum, especially for Verticillium dahlia.Following,the haematochrom producing by S.marcescens XJU-PA-6 was identified as 2-methyl-3-pentylcitamin (2M3PPG) by UV spectroscopy,nuclear magnetic resonance spectroscopy (NMR) and GC-MS.Also,the antigonitic michanisms of 2M3PPG to Verticillium dahliae was carried out using scanning electron microscopy (SEM),transmission electron microscopy (TEM) and GS-MS analysis,the results revealed 2M3PPG can inhibit the biosynthesis of erythropoietin,this event probably happened via inhibiting the activity of 14-α-demethylase in Verticillium dahlia.The results of this work showed that 2M3PPG has a very good potential application as biopesticide.

Key words: 2M3P Prodigiosin, Crop pathogens, Alternaria mali, inhibitory effect, mechanism