Study On The Sensitivity Of Melanin Synthesis Of Magnaporthe Grisea To Tricyclazole In Heilongjiang Province

Taking 116 Pyricularia grisea isolates as experimental materials in this experiment,by testing the growth and sporulation test,observating the colony color and quantitating determination of melanin in Heilongjiang Province.The results showed that: there was clear differences among the mycelium growth rates,the ability of creating spores and the ability of producing melanin of each Pyricularia grisea strains in Heilongjiang Province.The strains with the colony colour lighter and producing less melanin concentrations higher proportion in the tested strains.The result showed that the ability of producing melanin of Pyricularia grisea isolates was not very strong in Heilongjiang Province.But there was very different capacity of producing melanin between regions,between strains and strains in the region.It is known by further detection the sensitivity of strains to tricyclazole that there was nothing to do with the sensitivity of tricyclazole of the strains both the mycelium growth rates and the ability of creating spores.But the ability to produce melanin of the strain showed sensitivity to tricyclazole of the strain.The stronger ability to produce melanin of the strain, the higher value of MIC-H values and the MIC-A,the less sensitive to tricyclazole.Colony colour and bacteria strains produce melanin content showed significant positive correlation.Taking a combined application method of azure A assess of melanin concentrations to analysis quantitatively the ability of melanin synthesis.Determine the amount of bacteria on melanin synthesis to tricyclazole sensitive baseline(the value of EC50-H)was 0.1935μg·mL-1.According to the values of the sensitive to baseline based on 83 tested strains to tricyclazole sensitivity to analysis,Measured only 3 low resistance strains(3.61%),Other strains are sensitive strain,the result showed that there was the emergence of bacterial strains of being low to tricyclazole in Heilongjiang Province,However,most strains are still sensitive to performance.Tricyclazole can control rice blast in Heilongjiang Province as an effective pharmaceutical. Further studying inhibitive concentration of mycelium melanization(MIC-H)and inhibitive concentration of melanization in appressorial(MIC-A)to tricyclazole,The results show that the vast majority of strains of the MIC-H values were between the 0μg·mL-1～0.8μg·mL-1,MIC-H values between generations is stable;MIC-A values between generations has some volatility,However,different strains tricyclazole have greater sensitivity to different strains.MIC-H value of MIC-A value was positively correlated,but there was some differences between the range of changes.It showed quite different sensitivity of tricyclazole to Pyricularia grisea melanin biosynthesis Heilongjiang Province Paddy rice aera.In the same area or block it showed a big difference on the sensitivity of tricyclazole of the different strains isolated melanin biosynthesis.The result showed that the sensitivity of tricyclazole of Pyricularia grisea melanin biosynthesis is diverse in Heilongjiang Province.By determining the low-resistant strains and sensitive strains of colony diameter and sporulation,The results show that the bacteria strain tricyclazole sensitivity in melanin biosynthesis,mycelium growth ability and the performance of sporulation ability showed the same.The adaptation of lowed resistance strains and sensitive strains on the growth conditions were different. Sensitive strains to tricyclazole more appropriate under the growth conditions of the neutral(pH value of 7), The low-resistant strains were more suitable under the growth conditions of micro-alkaline(pH value of 8).In the high sugar and high salt medium,Low-resistant strains were more sensitive than the sensitive-strains to the high osmotic pressure.It was more conducive to the growth and production of various strains of melanin in potato medium,it was more conducive to sporulation of various strains in tomato medium.