摘要
小麦类过敏反应(hypersensitive reaction-like,HRL)是一类在没有病原物侵染情况下就能自发产生类似病原菌侵染后的过敏反应症状,这类突变往往导致小麦的抗病性增强和防御相关基因的组成性表达。本实验以携带HRL性状的宁7840为材料,对其进行EMS诱变和连续选择,筛选到14个比野生型的HRL表型更为明显的突变体。同时,对这14个突变体和野生型进行四个不同氮素水平处理(每盆分别施尿素0、3、6和9g),结果表明,宁7840野生型在低氮(施每盆0g和3g尿素)条件下,能够诱导HRL性状的提早表达,随着施氮量的增加,HRL性状延迟显现并逐渐消失(non-HRL),白粉病也随之加重,表现为氮依赖型;但在高氮(每盆施6g和9g尿素)条件下,有2个突变体(NMu-HRL^(-1)和NMu-HRL-2)依旧表现HRL性状,为非氮依赖型。通过比较13个氮依赖型(包括宁7840野生型)和2个非氮依赖型的HRL突变体氮肥吸收利用情况,发现两种类型突变体的氮肥吸收利用效率与施氮量都呈负相关,同一氮肥水平下,非氮依赖型突变体穗部的氮含量和氮素吸收利用效率都显著高于氮依赖型突变体。低氮条件下,非氮依赖型突变体的叶绿素含量显著低于氮依赖型突变体;高氮条件下,两种类型突变体植株内叶绿素含量差异不显著。在同一氮肥水平下,这两种类型的突变体之间白粉病严重度存在极显著差异,氮依赖型突变体在高氮条件下白粉病严重度极显著高于非氮依赖型突变体,非氮依赖型突变体在高氮条件下仍然高抗白粉病。
Wheat hypersensitive reaction-like(HRL)mutants are characterized as the formation of necrotic lesions without infection by pathogens,and such genetic defects often lead to enhanced resistance to pathogen infection and constitutive expression of defense response genes.In this study,we carried out EMS mutagenesis and continuous selection of progenies,and obtained 14 mutants with more obvious HRL phenotype than the wild type.Through treating the 14 mutants and the wild type with four levels of nitrogen(0 g,3 g,6 g and 9 g urea per pot),the results showed that low level of nitrogen(0 g and 6 g urea per pot)induced the early expression of HRL traits in the wild type.With the increase of nitrogen dosage,two mutants(NMu-HRL-1 and NMu-HRL-2)still showed HRL traits despite of high nitrogen conditions(6 g and 9 g urea per pot),thus they were nitrogen-independent mutants.The nitrogen fertilizer uptake and utilization efficiencies of the two types of mutants were negatively correlated with nitrogen levels.At the same nitrogen level,the panicle nitrogen fertilizer uptake and utilization efficiency of the nitrogen-independent mutant was significantly higher than that of the nitrogen-dependent mutant.Under low nitrogen conditions,the chlorophyll content of nitrogen-independent mutants was significantly lower than that of nitrogen-dependent mutants.There was no significant difference in chlorophyll content between the two types of mutant plants under high nitrogen conditions.Comparing the severities of powdery mildew in the 13 nitrogen-dependent(including the wild type)and the two nitrogen-independent mutants,we found that there was a significant difference in the severity of powdery mildew between the two types of mutants.The severities of powdery mildew on the nitrogen-dependent mutants were significantly higher than those of nitrogen-independent mutants under high nitrogen conditions.Nitrogen-independent mutants were still highly resistant to powdery mildew under high nitrogen conditions.
作者
施璇
李磊
郑彤
骆孟
李韬
SHI Xuan;LI Lei;ZHENG Tong;LUO Meng;LI Tao(Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology/Co-innovation Center for Modern Production Technology of Grain Crop/Key Laboratory of Plant Functional Genomics of Ministry of Education/Wheat Research Center,Yangzhou University,Yangzhou,Jiangsu 225009,China)
出处
《麦类作物学报》
CAS
CSCD
北大核心
2018年第4期410-417,共8页
Journal of Triticeae Crops
基金
国家自然科学基金项目(31600997
31270704)
扬州大学科技创新团队项目
江苏高校优势学科建设工程资助项目(PAPD)
关键词
小麦
类过敏反应
突变体
白粉病
氮素
Wheat
Hypersensitive reaction-like
Mutant
Powdery mildew
Nitrogen
