Free Radical Mechanism Of Wheat Resistance To Stripe Rust

Since its identification as an endothelium-derived relaxing factor in the 1980s, nitric oxide has becomes the source of intensive and exciting research in animal. Until recently,disease and induced HR markedly. The positive correlation was implied between resistance and NO dose and induced time. These suggest that NO is an important signal molecular, and NO induces a resistance of cultivar LovrinlO to the virulent race of P. striiformis West. The role of oligosaccharin on the systemic acquired resistance of wheat to stripe rustRecently, it attracted much more attention that applying the inductor to improve the plant defense system. Oligosaccharin is a special chemical signal, the pant defense reaction could be initiated and regulated by the oligosaccharin. The oligosaccharin came from the primary cell wall, the bank of oligosaccharide, which consisted of 90% polysaccharide and 10% protein. The oligosaccharin induced the resistance of host and hence decreased the disease. The oligosaccharin from the bean cell wall induced the resistance of Huixianhong to the virulent race CY29-1, which has been studied in this work. The endogenous NO of Huixianhong-CY29-l system has been detected by the ESR, from it the function of NO in the induced resistance was demonstrated. The NO curve of control was gradually increased, but that of treated with oligosaccharin presented twin peaks before the reproduced spores. This was the same as the same cultivar LovrinlO inoculating different stripe rust races. . The production of NO by wheat nitrate reductaseThe NO of animal unambiguous came from NOS, but the NO of plant was not limited to the organize containing NOS. The results reveal that part of NO came from the NR not only in immune system but also in HR resistant system, although the dynamic course was different. In general, the trend of NR in immune reaction was gradually increased, while that in HR reaction was a peak in the forth day after inoculation. The correlation between change of NR and NO in immune system was negative relative significantly, but that in HR resistance was positive. Further data revealed the correlation between the NO produced by NR and that by NOS was not significant in immune system, while that was positive relative markedly. All these results implicated that the contribution of NR to resistance in immune and HR reaction was very different.. The affection to NO production of nNOS-alike protein coming from the wheat leaveThe neural NOS-like protein was been blotted with the anti-mouse brain NOS coming from mouse Ig2a. The NOS was important to produce NO within animal and plant. The results in the work showed part of NO produced by structural NOS, and the NO coming from NOS was different in different reaction system as in different time point of inoculation. The contribution of NOS to NO was the most great in the key point of peak ofthe ability of plants to accumulate and metabolize NO has been known, and the its function as a signal in the plant defense responses against pathogen attracted a great deal of attention. Here, the relation between endogenous NO within wheat leaves and its resistant type to stripe rust has been studied by the technology of ESR. From the results, it was confirmed that the initiation time point and intensity were the key factors determining the phenotypes. Oligosaccharin and exogenous NO induced the resistance of wheat to virulent race of stripe rust, its provided evidence for the NO act as a signal molecular in the hypersensitive resistance. The research on the source of endogenous NO by ESR and western blot revealed the nitrate reductase and nitric oxide synthase all could produce NO in the pathosystem, although they contributed to the endogenous NO production differently. The time course of endogenous NO in the wheat inoculated different races ofstripe rustThe stripe rust (or yellow rust) caused by Puccinia striiformis Westend(.P striiformis West.) is a serious disease of wheat in many areas of the world. The role of NO in wheat stripe rust was...