陆地棉种质黄萎病抗性生理鉴定分析

Physiological identification and analysis of Verticillium wilt resistance of 10 foreign cotton germplasm resources

【目的】研究陆地棉种质黄萎病抗性及生理鉴定,为棉花黄萎病抗性品种选育提供数据支持。【方法】以10份国外棉花种质(Gossypium hirsutum)为材料对室内盆栽棉花接种大丽轮枝菌(Verticillium dahliae Kleb),菌液浓度为107 CFU/mL,接菌14 d后,观察并记录表型发病情况;采用荧光定量PCR检测叶片的菌含量;测定棉花叶片的木质素、过氧化氢(H_(2)O_(2))、苯丙氨酸解氨酶(PAL)、丙二醛(MDA)和脯氨酸(PRO)等生理生化指标,结合相关性、主成分、隶属函数和聚类分析等方法,综合评价棉花的5个生理指标抗性。【结果】03804、A-6、04841和05189发病较轻;03804和A-6病菌DNA含量最少;在病菌侵染过程中,这些品种对PAL、PRO、木质素等的依赖程度不同,呈现出品种间差异;当棉花受到V.dahliae侵染后,MDA与H_(2)O_(2)呈极显著正相关,与PAL和PRO呈极显著负相关;五项抗病指标通过简化得到2个主成分,贡献率分别为64.951%,20.386%;10份材料根据棉花抗病综合指标可划分为1份抗病(03804)、5份耐病(05160、A-6、A-688、A-91、A-924)和4份易感病(04219、04841、A-1139、05189)材料。【结论】筛选出1份抗病、5份耐病和4份易感病的陆地棉种质。

【Objective】Physiological identification and analysis of Verticillium wilt resistance of 10 foreign cotton germplasm resources,and provide data support for the breeding of Verticillium wilt resistance in China.【Methods】To study the Verticillium wilt resistance of 10 foreign cotton varieties(Gossypium hirsutum),The concentration of Verticillium dahliae Kleb infecting cotton seedling was 107 spores/mL.After 14 days of inoculation,the morphology and phenotype were observed and photographed.Real-time PCR was used to determine the pathogene content in cotton leaves.The physiological and biochemical indexes(lignin,hydrogen peroxide(H_(2)O_(2)),phenylalanine ammonia lyase(PAL),malondialdehyde(MDA)and proline(PRO)in cotton leaves were determined.Correlation analysis,principal component analysis,subordinate function analysis and cluster analysis were conducted to evaluate the cotton resistance.【Results】Phenotypic results showed that 03804,A-6,04841 and 05189 had mild incidence.The results of qPCR showed that the 03804 and A-6 contained the least pathogene.In the course of pathogen infection,these varieties had different dependence on PAL,Proline,lignin,etc.,indicating different characteristics of varieties.Correlation analysis showed that MDA was significantly positively correlated with H_(2)O_(2) and negatively correlated with PAL and Proline after V.dahliae infection in cotton.Principal component analysis showed that two principal components were obtained from the five resistance indexes,and their contribution rates covered 64.951%and 20.38%,respectively.Analyzed by subordinate function and hierarchical cluster of comprehensive index of cotton disease resistance,10 cotton cultivars could be divided into three categories,including one resistance,five tolerance and four susceptible cultivars.【Conclusion】H_(2)O_(2),PAL,MDA,PRO and lignin content can be used as physiological indexes for the identification of Verticillium wilt resistance in cotton.In this study,one disease-resistant,five disease-tolerant and four susceptible foreign land cotton germplasm are identified by morphological and physiological index after Verticillium dahliae Kleb infection.