| Gray mold,caused by Botrytis cinerea is one of the TOP 10 diseases around the world,which was found in 200 kinds of plant diseases,tomatoes,grapes,strawberries included.Application of fungicides to this disease is the most commonly used approaches for the pathogen has high capacity of sporulation,active transposon and get genetic variation easily.But varieties of fungicides for the control of gray mold conferred resistance to from pathogen occured,or even lose their function.As a new type of fungicide,fludioxonil have great effects on the control of gray mold with unique site of action.Fludioxonil has been registered for use in many countries,but its use is still in the ealy stage in our country and it has been gradually used to control the gray mold in recent years.Although it has been reported that the site of action of fludioxonil may be histidine kinase of type III and related to HOG pathway,the mechanism of action and resistance mechanism of it is still unclear.As upstream elements of the two branches in HOG pathway,I construct deletion mutant and completely or partly complementary mutants of BcShol,deletion mutant of BcSlnlas well as double deletion mutant of BcSlnl and BcShol also been constructed in this study to research the biological function of this two genes and the relationship between them.GFP marker localization revealed that the BcShol protein was located in the cell membrane of hyphae,and the protein is in cytoplasm after the removal of transmembrane domain.In this study,it is found that the deletion mutant of BcShol show a slightly decrease in susceptibility to fludioxonil,but there is no significant differences when campared to the complementary mutants of BcShol.However,it is not the target of action of fludioxonil in Botrytis cinerea.It was also found that the gene was involved in the regulation of susceptibility of Botrytis cinerea to oxidative stress and cell wall stress factor,but not to pathogenicity.The gene plays an important role in the hyphae growth,the sensitivity to temperature,glycerol synthesis,ability of utilize different nitrogen source and adaptability to alkaline environment.And its transmembrane domains are involved in regulating the adaptability to alkaline environments of Botrytis cinerea.Study in this chapter is accomplished by construct deletion mutant and completely or partly complementary mutants of BcShol.Gene BcSlnl was proved to be not associated with resistance to procymidone in Botrytis cinerea.The BcSlnl deletion mutant did not change susceptibility to fludioxonil,but the concentration of glycerol in the cells was increased in the condition of fludioxonil treatment.However,the double deletion mutant ?BcSlnl-Shol increased the susceptibility to fludioxonil,while there is no significant difference of glycerol production capacity compared to the wild-type strain B05.10.This indicates that there might be other compensatory pathway or related mechanisms.Gene BcSlnl is not associated with the pathogenicity and the regulation of temperature of Botrytis cinerea,but it is reated to the sensitivity of the osmotic stress,oxidative stress and cell wall stress factor from different types of compounds,while there was a difference among these responses.BcSlnl have an impact on the tolerance of Botrytis cinerea to the alkaline environment,however there is no obvious interaction between Gene BcShol and Gene BcSlnl.It was also founded that BcSlnl and BcShol were involved in the regulation of the utilization ability to different nitrogen sources of Botrytis cinerea,and there seems to be an interaction between them.Study in this chapter is accomplished by construct deletion mutant of BcSlnl and double deletion mutant of BcSlnl and BcShol. |
PDF Full Text Request