03-08-2013, 04:23 PM
Phytopathogenomics in Plant Disease Management: A Paradigm Shift
ABSTRACT
Plant pathogens are an important constraint to global crop production. It has been estimated that an average of 10-30% of crop yield is lost annually. As a consequence, crop diseases represent a significant threat to ensuring global food security. To feed the growing human population it will be necessary to double food production by 2050, which will require the sustainable intensification of agriculture in an era of unpredictable climate change. Management of the important plant diseases represents one of the best means of delivering as much of the current productivity of crops as possible. To accomplish this task, a fundamental understanding of the biology of plant infection by disease-causing agents, such as bacteria, and fungi is necessary. In this scenario, the major obstacle is that the plant pathogens are moving targets that evolve in response to agricultural practices and environmental changes. The emergence and spread of new diseases, or more aggressive or fungicide-resistant pathotypes are examples of such evolution. Thus, the key issues facing plant pathologists in the 21st century is to devise pathogen diagnostics and disease management systems that are sustainable and not compromised by the evolution of virulent and aggressive pathogen strains.
Harnessing new technologies and knowledge to create more durable resistant crops and sustainable disease management systems will require improved understanding of the factors driving plant pathogen adaptation and evolution. As a result, phytopathogenomics may be the probable answer to enhance the speed, sensitivity and accuracy of pathogen detection and to identify regulatory genes, signal molecules, pathways and networks controlling induced plant defense for intervention via novel chemistry or genetic modification (GM). At its core, GM depends on the ability to transfer specific genetic information from one organism to another and that information to be recognized and utilized by the new host. This genetic process is independent of natural species barriers so can be used to transfer DNA between kingdoms: for example, to engineer pathogen resistance in crop plants by transferring a gene from a bacterium or a fungus.