Oxidative burst is one of the earliest responses in plant resistance to pathogen attack. Studies indicate that the oxidative burst is composed of two phases. The first burst is weak and biologically nonspecific, where...Oxidative burst is one of the earliest responses in plant resistance to pathogen attack. Studies indicate that the oxidative burst is composed of two phases. The first burst is weak and biologically nonspecific, whereas the phase Ⅱ burst is massive and produced only as an incompatible interaction. The rapid transient production of active oxygen species plays an important role in plant defense strategy against diseases. It involves: 1) antimicrobial activity, 2) substrate for oxidative cross_linking of cell wall, 3) triggering factor of hypersensitive response, 4) mobile signal inducing local and systemic acquired resistance by itself or its derivatives, 5) induction of phytoalexin accumulation, and 6) regulation of gene transcription. Emerging data indicate that the oxidative burst initiates from the activation of NADPH oxidase system resembling that of animal phagocytes. The generation of active oxygen species by a pH_dependent peroxidase is also present in some plants. Further, there is a complete system in plants to regulate the accumulation and scavenging of active oxygen species to protect plants from secondary infection, and at the same time to avoid the oxidative stress.展开更多
Osmotic stress is generally referred to situations where insufficient water availability limits plant growth and development.the responses to osmotic stress are complex in plant.In this review,some osmotic stress\|res...Osmotic stress is generally referred to situations where insufficient water availability limits plant growth and development.the responses to osmotic stress are complex in plant.In this review,some osmotic stress\|responsive genes in plants have been reported and their possible roles have been discussed.Studies on the regulation of osmotic stress\|responsive genes have been made progress in recent years and some results have also been reported here.These studies aim to understand how plant cells perceive the osmotic stress signal and transduce this signal to produce changes in osmotic stress\|responsive gene expression.\;展开更多
文摘Oxidative burst is one of the earliest responses in plant resistance to pathogen attack. Studies indicate that the oxidative burst is composed of two phases. The first burst is weak and biologically nonspecific, whereas the phase Ⅱ burst is massive and produced only as an incompatible interaction. The rapid transient production of active oxygen species plays an important role in plant defense strategy against diseases. It involves: 1) antimicrobial activity, 2) substrate for oxidative cross_linking of cell wall, 3) triggering factor of hypersensitive response, 4) mobile signal inducing local and systemic acquired resistance by itself or its derivatives, 5) induction of phytoalexin accumulation, and 6) regulation of gene transcription. Emerging data indicate that the oxidative burst initiates from the activation of NADPH oxidase system resembling that of animal phagocytes. The generation of active oxygen species by a pH_dependent peroxidase is also present in some plants. Further, there is a complete system in plants to regulate the accumulation and scavenging of active oxygen species to protect plants from secondary infection, and at the same time to avoid the oxidative stress.
文摘Osmotic stress is generally referred to situations where insufficient water availability limits plant growth and development.the responses to osmotic stress are complex in plant.In this review,some osmotic stress\|responsive genes in plants have been reported and their possible roles have been discussed.Studies on the regulation of osmotic stress\|responsive genes have been made progress in recent years and some results have also been reported here.These studies aim to understand how plant cells perceive the osmotic stress signal and transduce this signal to produce changes in osmotic stress\|responsive gene expression.\;
