PDF(Pubmed)
Abstract：
Nitrogen (N) and silicon (Si) are mineral elements that have shown a reduction in the damage caused by tan spot (Pyrenophora tritici-repentis (Ptr)) in wheat. However, the effects of these elements were studied separately, and the N and Si interaction effect on wheat resistance to tan spot remains elusive. Histocytological and biochemical defense responses against Ptr in wheat leaves treated with Si (+Si) at low (LN) and high N (HN) inputs were investigated. Soil amendment with Si reduced the tan spot severity in 18% due to the increase in the leaf Si concentration (around 30%), but it was affected by the N level used. The superoxide dismutase (SOD) activity was higher in +Si plants and inoculated with Ptr, leading to early and higher H2O2 and callose accumulation in wheat leaf. Interestedly, phenylalanine ammonia-lyase (PAL) activity was induced by the Si supplying, being negatively affected by the HN rate. Meanwhile, catalase (CAT), and peroxidase (POX) activities showed differential response patterns according to the Si and N rates used. Tan spot severity was reduced by both elements, but their interaction does not evidence synergic effects in this disease\'s control. Wheat plants from -Si and HN and +Si and LN treatments recorded lower tan spot severity.
摘要：
氮（N）和硅（Si）是矿物元素，显示出减少了小麦中棕褐色斑点（Pyrenophoratritici-repatentis（Ptr））造成的损害。然而,分别研究了这些元素的作用，N和Si交互作用对小麦抗棕褐色斑病的影响仍然难以捉摸。研究了在低（LN）和高N（HN）输入下用Si（Si）处理的小麦叶片中针对Ptr的组织细胞和生化防御反应。由于叶片Si浓度的增加（约30％），Si的土壤改良剂降低了18％的棕褐色斑点严重程度，但它受到使用的N水平的影响。在+Si植物和接种Ptr中，超氧化物歧化酶(SOD)活性较高，导致小麦叶片早期和较高的H2O2和call体积累。有趣的是，硅供应诱导苯丙氨酸解氨酶（PAL）活性，受到HN率的负面影响。同时,过氧化氢酶(CAT),根据使用的Si和N速率，过氧化物酶（POX）活性显示出不同的响应模式。这两种元素都降低了棕褐色斑点的严重程度，但它们的相互作用并不能证明在这种疾病的控制中具有协同作用。来自-Si和HN以及+Si和LN处理的小麦植株记录到较低的棕褐色斑点严重程度。
