链霉菌JD211对接种稻瘟病后水稻过敏性反应的生理机制分析

摘要

In order to investigate the effect of Streptomyces JD211 on physiological mechanism of hypersensitive response in rice after inoculation with Magnaporthe grisea,with the rice variety "Luliangyou 996" as materials,we conducted pot experiments by applying powdered Streptomyces JD211 cultivation of rice and inoculated with rice blast fungus spore suspension,and then sprayed with water as control,hydrogen peroxide (H2O2),catalase (CAT),lipoxygenase (LOX),malondialdehyde (MDA) and cell membrane permeability in rice leaves were determined.The results showed that: (1) when the rice seedling age was 30 days,the treatment group with adding Streptomyces JD211,(CAT),(LOX) and (H2O2) increased by 50.30%,40.85% and 45.31%,respectively compared with the control group and (MDA) decreased by 25.75%.(2) After inoculate with Magnaporthe grisea,plus JD211 treatment group,(CAT),(LOX) and (H2O2) were increased by 33.50%,4.07% and 47.76% than that of the group without JD211,MDA decreased by 38.68%.(3) After inoculation of Magnaporthe grisea,the JD211 treatment group compared to the group without JD211,cell membrane permeability increased by 38.94%,39.03% and 8.08% at the age of 32 days,34 days,36 days,respectively.It is considered that Streptomyces JD211 enhanced the content of H2O2,and the activities of CAT and LOX,while inhibited the accumulation of MDA.The cell membrane permeability also increased with the inoculation of Magnaporthe grisea in the later stages,which can effectively regulate the hypersensitive response in the cell,induced cell necrosis,further prevented pathogens infection,and effectively improved rice resistance to rice blast.%以水稻品种"陆两优996"为材料,采用盆栽试验,通过施加链霉菌JD211固体菌剂培育水稻,以叶片喷施稻瘟病菌孢子悬液接种稻瘟病菌为处理,以喷施清水为对照,测定分析水稻叶片过氧化氢(H2O2)含量、过氧化氢酶(CAT)活性、脂氧合酶(LOX)活性、丙二醛(MDA)含量及细胞质膜透性等生理生化指标变化,探究链霉菌JD211对接种稻瘟病后水稻过敏性反应的生理机制.结果表明:(1)水稻秧龄30 d时,只添加链霉菌JD211处理组水稻的叶片CAT活性、LOX活性、H2O2含量较对照组分别显著提高50.30%、40.85%和45.31%,其MDA含量显著降低25.75%.(2)接种稻瘟病菌后添加JD211处理组水稻的叶片CAT活性、LOX活性、H2O2含量较未添加JD211处理组(只接种稻温病菌处理组)分别提高了33.50%、4.07%和47.76%,其MDA含量降低了38.68%.(3)接种稻瘟病菌后添加JD211处理组的细胞膜透性较未添加JD211处理组在秧龄32、34和36 d时分别提高了38.94%、39.03%和8.08%.研究认为,施加链霉菌JD211提高了水稻叶片过氧化氢含量、过氧化氢酶以及脂氧合酶活性,抑制了丙二醛积累,在后期增加了接种稻瘟病菌处理组的细胞膜透性,从而能够有效调控细胞过敏性反应,诱发细胞过敏性坏死,阻止病原菌的进一步侵染,有效提高水稻稻瘟病抗性.