不同梨种质叶片结构及防御酶活性与火疫病抗性的关联分析  

Association analysis of leaf structure and defense enzyme activity with fire blight resistance in different pear germplasms

作　　者：王贝贝 田嘉 WANG Beibei;TIAN Jia(College of Horticulture,Xinjiang Agricultural University,Urumqi 830052)

机构地区：[1]新疆农业大学园艺学院,乌鲁木齐830052

出　　处：《中国果树》2024年第10期113-123,共11页China Fruits

基　　金：新疆维吾尔自治区天山创新团队(2023D14015);新疆农业大学研究生科研创新项目(XJAUGRI2023017)。

摘　　要：为了明确梨火疫病与叶片结构和防御酶活性的关系,以课题组前期筛选的抗火疫病杜梨为研究对象,以普通杜梨、库尔勒香梨和秋子梨为对照,采用刻伤接种法对4份梨种质进行抗性评价,观察并测定叶片的蜡质含量、气孔特征、叶片横切结构以及6个防御酶活性等指标,利用方差分析和相关性分析研究叶片结构、防御酶活性与梨火疫病抗性的关系。结果表明,4份梨种质抗火疫病能力由强到弱为抗病杜梨(MR)≈秋子梨(MR)>普通杜梨(S)≈库尔勒香梨(S)。叶片蜡质含量与病情指数不存在显著相关性;气孔密度、叶片厚度、上表皮厚度、下表皮厚度与病情指数的相关系数分别为0.959、0.951、0.978和0.991,均呈显著或极显著正相关。接种火疫病菌后,有效提高了叶片SOD、CAT、PPO、PAL活性,且抗病种质高于感病种质,而抗病种质的MDA含量下降幅度最大(抗病杜梨和秋子梨分别下降了48.33%、38.42%)。因此,梨叶片的下表皮厚度可作为初步衡量火疫病抗性能力的指标,气孔密度、叶片厚度和上表皮厚度可作为辅助参考指标;防御酶中SOD、CAT、PPO、PAL活性以及MDA含量的变化最为明显,6种防御酶活性峰值的高低可以初步作为早期鉴定梨抗火疫病的生理指标,可为抗病梨种质资源选育提供新思路和奠定理论基础。In order to clarify the relationship between pear fire blight and leaf structure and defense enzyme activity,the anti fire disease resistant Pyrus betulifolia Bunge.selected by the research group in the early stage was taken as the research object,and ordinary Pyrus betulifolia Bunge.,‘Korla fragrant pear’and Pyrus ussuriensis Maxim.were used as controls,and evaluated the resistance of four pear germplasms by the method of incised inoculation,observing and measuring the wax content of the leaves,the stomatal characteristics,the transverse structure of the leaves as well as the six defense enzyme activity indexes,and using analysis of variance(ANOVA)and correlation studies to study the relationship of leaf structure and defense enzyme activity with the resistance to pear fire blight.The results showed that the resistance of four pear germplasms to fire blight was as follows:resistant Pyrus betulifolia Bunge.(MR)≈Pyrus ussuriensis Maxim.(MR)>ordinary Pyrus betulifolia Bunge.(S)≈‘Korla fragrant pear’(S).There was no significant correlation between leaf wax content and disease index.The correlation coefficients between stomatal density,leaf thickness,upper epidermal thickness,and lower epidermal thickness and disease index were 0.959,0.951,0.978,and 0.991,respectively,all showing significant or extremely significant positive correlation.After inoculation with Erwinia amylovora,the activities of SOD,CAT,PPO,and PAL in the.leaves were effectively increased,and the resistant germplasm was higher than the disease-susceptible germplasm.The MDA content of the disease-resistant germplasm decreased the most(the resistant Pyrus betulifolia Bunge.and Pyrus ussuriensis Maxim.decreased by 48.33%and 38.42%,respectively).Therefore,the lower epidermal thickness of pear leaves can be a preliminary indicator of fire blight resistance,while the stomatal density,the thickness of the leaves,and upper epidermal thickness can be used as an auxiliary reference index;the changes in SOD,CAT,PPO,PAL activity and MDA content were m

关 键 词：梨 火疫病 叶片结构 酶活性 抗性 

分 类 号：S661.2[农业科学—果树学]