Melanin,DNA replication,and autophagy affect appressorium development in Setosphaeria turcica by regulating glycerol accumulation and metabolism  

作　　者：GUO Xiao-yue LIU Ning LIU Bing-hui ZHOU Li-hong CAO Zhi-yan HAN Jian-min DONG Jin-gao 

机构地区：[1]State Key Laboratory of North China Crop Improvement and Regulation/Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology/Mycotoxin and Molecular Plant Pathology Laboratory,Hebei Agricultural University,Baoding 071001,P.R.China

出　　处：《Journal of Integrative Agriculture》2022年第3期762-773,共12页农业科学学报（英文版）

基　　金：supported by the grants from the National Natural Science Foundation of China(32072370 and 31901827);the China Agriculture Research System of MOF and MARA(CARS-02-25);the Natural Science Foundation of Hebei Province,China(C2020204039 and C2018204059);the Projects of Overseas Foundation,Hebei Province,China(C20190508)。

摘　　要：Setosphaeria turcica(syn.Exserohilum turcicum)is the pathogenic fungus of maize(Zea mays)that causes northern leaf blight,which is a major maize disease worldwide.Melanized appressoria are highly specialized infection structures formed by germinated conidia of S.turcica that infect maize leaves.The appressorium penetrates the plant cuticle by generating turgor,and glycerol is known to be the main source of the turgor.Here,the infection position penetrated by the appressorium on maize leaves was investigated,most of the germinated conidia entered the leaf interior by directly penetrating the epidermal cells,and the appressorium structure was necessary for the infection,whether it occurred through epidermal cells or stomata.Then,to investigate the effects of key factors in the development of the appressorium,we studied the effects of three inhibitors,including a melanin inhibitor(tricyclazole,TCZ),a DNA replication inhibitor(hydroxyurea,HU),and an autophagy inhibitor(3-methyladenine,3-MA),on appressorium turgor and glycerol content.As results,appressorium turgor pressure and glycerol concentration in the appressorium reached their highest levels at the mature stage of the appressorium under the control and inhibitor treatments.The three inhibitors had the greatest effects on appressorium turgor pressure at this stage.Glycogen and liposomes are the main substances producing glycerol.It was also found inhibitors affected the distribution of glycogen and liposomes,which were detected in the conidia,the germ tube,and the appressorium during appressorium development.This study provides profound insight into the relationship between appressorium turgor pressure and glycerol content,which was affected by the synthesis of melanin,DNA replication,and autophagy in the developing appressorium during a S.turcica infection.

关 键 词：MELANIN DNA replication AUTOPHAGY APPRESSORIUM DEVELOPMENT Setosphaeria turcica GLYCEROL 

分 类 号：S435.131.4[农业科学—农业昆虫与害虫防治]