2种化感物质胁迫下内生真菌感染对木麻黄幼苗小枝活性氧代谢和清除系统的影响  

Effects of endophyte infection on reactive oxygen content and protective enzyme activity in branchlet of Casuarina equisetifolia seedling under stress of two allelochemicals

作　　者：龙凤[1] 洪滔[1] 林勇明[1] 谢安强[1] 吴承祯[1,2] 洪伟[1] 李键[1] 

机构地区：[1]福建农林大学林学院,福州350002 [2]武夷学院生态与资源工程学院,南平354300

出　　处：《应用与环境生物学报》2016年第3期462-472,共11页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金项目(314 0 0533);福建省自然科学基金项目(2014J01074);福建农林大学校重点项目建设专项(6112C039K)资助~~

摘　　要：为探讨使用木麻黄-内生真菌共生体应对连栽障碍的可能性,在前期已获得2种木麻黄化感物质(槲皮黄素-3-α-阿拉伯糖苷,Q3A;槲皮黄素-3-β-葡萄糖苷,Q3B)胁迫对木麻黄(Endophyte-free,EF)幼苗小枝活性氧代谢和清除系统影响的基础上,本研究以感染(Endophyte-infected,EI)内生真菌Aspergillus sp.的木麻黄水培幼苗(Casuarina equisetifolia Forst.)为实验材料,在控制环境水培条件下,分析内生真菌对Q3A和Q3B胁迫下木麻黄幼苗小枝活性氧代谢和清除系统的影响.结果显示,内生真菌的侵染能够有限缓解木麻黄化感物质的胁迫,在中度轻度及短期胁迫(100 mg/L 0-12 h、50 mg/L 0-24 h、25 mg/L 0-36 h、12.5 mg/L 0-48 h)下有明显的效果,表现在与木麻黄EF相比,木麻黄EI活性氧含量显著下降,丙二醛(MDA)含量显著降低,保护酶活性显著增加;内生真菌缓解化感物质胁迫的有效浓度和胁迫期与木麻黄EF能够耐受的化感物质胁迫浓度和胁迫期一致;Q3A胁迫下木麻黄EI保护酶活性显著高于Q3B胁迫下的提升幅度.说明内生真菌提升了宿主木麻黄的抗逆性,对宿主应对Q3A胁迫的贡献更大,推测内生真菌对木麻黄EI保护酶系统的提升需要建立在木麻黄保护酶系统合成和降解还未受到不可逆伤害的前提下.(图6表1参40)This research aimed to explore the possibility of using endophytic fungi-Casuarina equisetifolia Forst. seedling symbiont to alleviate the continuous？planting？obstacles. It was based on the previous research on the effect of two allelochemicals （quercetin-3-α-araboside, Q3A; quercetin-3-β-glucoside, Q3B） on the reactive oxygen contents and activities of scavenging enzymes in branchlets of Casuarina equisetifolia Forst. seedlings free （EF） from endophyte （Aspergillus sp.）. We studied the effect of Q3A and Q3B on the reactive oxygen contents and activities of scavenging enzymes in branchlets of Casuarina equisetifolia Forst. Seedlings infected with （EI） endophyte （Aspergillus sp.） by addition of allelochemicals to the water （of seven concentrations： 0, 12.5, 25, 50, 100, 200 and 400 mg/L） for 0-72 h to analyse the effect of endophyte infection. The results showed that the endophytic fungus colonization alleviated the allelochemical stress intensity to some degree and the effect was obvious in slight allelochemical stress at the early stage （100 mg/L 0-12 h, 50 mg/L 0-24 h, 25 mg/L 0-36 h, 12.5 mg/L 0-48 h）, mainly in the reactive oxygen and its scavenging system; endophyte infection significantly reduced the production of hydrogen peroxide （H2O2）, malondlaldehyde （MDA） and superoxide radical （O2-）. At the same time, endophyte infection significantly improved the activity of protective enzymes such as superoxide dismutase （SOD）, peroxidase （POD） and catalase （CAT）. But the effective concentration and stress time was in accordance with those that Casuarina equisetifolia Forst. EF endured, which showed that the protective enzyme system of C. equisetifolia. EI which was improved by endophytic fungus needed to be built before protective enzyme system synthesis and degradation suffered from lethal harms. EI had higher activities of protective enzyme activity under Q3A stress than under Q3B stress. The results of our experiment indicated that endophyte infection

关 键 词：化感胁迫 内生真菌 木麻黄 活性氧含量 保护酶活性 

分 类 号：S792.93[农业科学—林木遗传育种]