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Induced Disease Resistance in Plants by Chemicals 总被引:23,自引:0,他引:23
Michael Oostendorp Walter Kunz Bob Dietrich Theodor Staub 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(1):19-28
Plants can be induced locally and systemically to become more resistant to diseases through various biotic or abiotic stresses. The biological inducers include necrotizing pathogens, non- pathogens or root colonizing bacteria. Through at network of signal pathways they induce resistance spectra and marker proteins that are characteristic for the different plant species and activation systems. The best characterized signal pathway for systemically induced resistance is SAR (systemic acquired resistance) that is activated by localized infections with necrotizing pathogens. It is characterized by protection against a broad range of pathogens, by a set of induced proteins and by its dependence on salicylic acid (SA) Various chemicals have been discovered that seem to act at various points in these defense activating networks and mimic all or parts of the biological activation of resistance. Of these, only few have reached commercialization. The best- studied resistance activator is acibenzolar-5-methyl (BION). At low rates it activates resistance in many crops against a broad spectrum of diseases, including fungi, bacteria and viruses. In monocots, activated resistance by BION typically is very long lasting, while the lasting effect is less pronounced in dicots. BION is translocated systemically in plants and can take the place of SA in the natural SAR signal pathway, inducing the same spectrum of resistance and the same set of molecular markers. Probenazole (ORYZEMATE) is used mainly on rice against rice blast and bacterial leaf blight. Its mode of action is not well understood partly because biological systems of systemically induced resistance are not well defined in rice. Treated plants clearly respond faster and in a resistant manner to infections by the two pathogens. Other compounds like beta-aminobutyric acid as wdl as extracts from plants and microorganisms have also been described as resistance inducers. For most of these, neither the mode of action nor reliable pre-challenge markers are known and still other pathways for resistance activation are suspected. Resistance inducing chemicals that are able to induce broad disease resistance offer an additional option for the farmer to complement genetic disease resistance and the use of fungicides. If integrated properly in plant health management programs, they can prolong the useful life of both the resistance genes and the fungicides presently used. 相似文献
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Eduardo Segundo Dietrich E. Lesemann Germán Martín María P. Carmona Leticia Ruiz Isabel M. Cuadrado Leonardo Velasco Dirk Janssen 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(1):81-87
Amaranthus leaf mottle virus (AmLMV) was classified as a member of the genus Potyvirus on the basis of its particle morphology, serology, and biological properties (Casetta et al., 1986). Based on these properties, an Amaranthus viridis-infecting virus isolated in Spain, causing mottle and leaf blistering as well as reduced growth has been identified as AmLMV.
The 3′ terminal genomic region of this and a reference isolate from Italy has been sequenced and reveals a 95% nucleotide
identity between the two isolates. The sequenced part comprises the coat protein with 281 amino acids and 315 nucleotides
of the 3′ untranslated region (UTR) preceding a polyadenylated tail. Pairwise comparisons and phylogenetic analysis of the
nucleotide and deduced amino acid sequences of the CP and 3′ UTR of the cloned cDNAs with those of other potyviruses shows
that AmLMV is a distinct potyvirus closely related to Potato virus Y. 相似文献
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We conducted a satellite tracking study of the endangered short-tailed albatross (Phoebastria albatrus) to determine post-breeding season distribution, the amount of time spent within exclusive economic zones of Pacific Rim countries, and assess factors affecting spatial and temporal overlap with commercial fisheries in Alaska. We obtained 6709 locations for 14 albatrosses (131-808 locations and 51-138 days of tracking per bird). Albatrosses ranged widely throughout the North Pacific Rim, spending the majority of time within the exclusive economics zones of Japan, Russia (Kuril Islands and Kamchatka Peninsula), and the United States (Aleutian Islands and Bering Sea, Alaska). We found evidence for gender and age-related differences in distribution and, therefore, potential interaction with regional fisheries. Overall, albatrosses spent the greatest proportion of time within the Alaska exclusive economic zone. Within Alaska, albatrosses occurred most frequently in fishery management zones that encompassed the Aleutian Islands, Bering Sea, and south of the Alaska Peninsula. Short-tailed albatrosses had the greatest potential overlap with fisheries that occurred along continental shelf break and slope regions, e.g., longlining for sablefish (Anoplopoma fimbria), where albatrosses occurred most often. Some birds, however, also made frequent excursions onto the extensive Bering Sea shelf, suggesting significant potential for interactions with the large-scale walleye pollock (Theragra chalcogramma) and Pacific cod (Gadus macrocephalus) fisheries. Alaskan longline fishing fleets have been proactive in using seabird deterrent devices, however, our data further emphasize that such efforts beyond the Alaska exclusive economic zone would provide a greater conservation benefit for this species. 相似文献