向日葵与锈菌互作过程中活性氧的积累

为了探讨向日葵品种与锈菌互作中活性氧的产生和积累与向日葵抗锈病性的关系,采用分光光度计法及联苯胺蓝(DAB)、氮兰四唑(NBT)染色法对过氧化氢(H2O2)及超氧阴离子自由基(O2-)诱导积累的过程进行了检测.结果表明:接种后抗、感病品种均出现H2O2和O2-双峰,侵染早期积累明显,最高峰出现在16 h,在抗病品种中活性氧产生和积累明显高于感病品种;在抗病品种中侵染位点活性氧的产生及积累较明显,接种后16h,侵染位点周围的染色范围较大,染色较深,H2O2及O2-的染色比例均达到最高,分别为65.5%和41%;而在感病品种的侵染位点没有检测到明显的活性氧积累.

The accumulation of active oxygens during the interactions of sunflower and rust fungus

Our study analyzed the relationship between the different resistant sunflower varieties inoculated with Puccinia helianthi Schw. and the accumulation of active oxygen. H₂O₂ content and O₂^- production rate of different sunflower varieties were tested with spectrophotometers; detection of H₂O₂ and O₂^-were carried out using the 3,3-diaminobenzidine (DAB) and nitroblue tetrazolium (NBT). The results revealed that in susceptible and resistant varieties active oxygen presented the double peak trends, rapid increment of active oxygen was obvious at the early stage of infection, 16 hours after inoculation (hai), H₂O₂ and O₂^- reached to the highest peak; the accumulation of active oxygen in resistant varieties was significantly higher than that in the susceptible. It was observed by in situ stain that in resistant varieties, stain range was wide and deep. The percentage of infection sites showing NBT and DAB staining all reached the highest 65.5% and 41%, respectively, 16 h after inoculation (hai). But no obvious stain was observed in susceptible varieties, suggesting the positive correlation of the accumulation of H₂O₂ and O₂^- with the resistance level of sunflower to rust disease.