AM真菌摩西管柄囊霉对干旱胁迫下枳抗氧化酶基因表达的影响

测定分析了接种丛枝菌根（AM）真菌摩西管柄囊霉Funneliformis mosseae对正常供水与干旱处理的盆栽枳Poncirus trifoliata实生苗生长、活性氧代谢及抗氧化酶基因表达量的影响。结果表明,7周干旱处理显著降低了根系菌根侵染率。接种摩西管柄囊霉显著促进了干旱处理的枳植株生长,增加了根系体积和叶片相对含水量,显著降低了叶片脯氨酸含量,同时也上调了干旱处理的枳叶片精氨酸脱羧酶基因（PtADC1和PtADC2）和超氧化物歧化酶基因（PtFe-SOD和PtMn-SOD）、过氧化物酶基因（PtPOD）和过氧化氢酶基因（PtCAT1）的表达,因而维持了一个相对更低的活性氧水平（如过氧化氢）,有利于增强植株的抗旱性。

Effects of Funneliformis mosseae on the expression of antioxidant enzyme genes in trifoliate orange exposed to drought stress

The effects of inoculation of an arbuscular mycorrhizal (AM) fungus Funneliformis mosseae on plant growth, reactive oxygen species metabolism, and expression of relevant antioxidant enzyme genes of potted trifoliate orange (Poncirus trifoliata) seedlings under well-watered and drought stress conditions were evaluated. After seven weeks of drought treatment, root mycorrhizal colonization was significantly reduced. F. mosseae inoculation significantly promoted plant biomass, root volume and leaf relative water content and reduced leaf proline concentrations under drought stress conditions. F. mosseae also markedly up-regulated the expression of arginine decarboxylase genes (PtADC1 and PtADC2), superoxide dismutase genes (PtFe-SOD and PtMn-SOD), peroxidase gene (PtPOD) and catalase 1 gene (PTCAT1) in leaves under drought stress, thereby maintaining considerably lower reactive oxygen species (e.g., hydrogen peroxide) levels. The results come to the conclusion that mycorrhizal plants possess strong antioxidant defense capacity to enhance drought tolerance.