Zahra Amjadi , Habiballah Hamzehzarghani,
Volume 3, Issue 1 (3-2014)
Abstract
Metabolomics or analysis of all cellular metabolites is a new and powerful tool that provides possible quick view to the large number of small molecules (metabolites) within the cell and indicates dynamics of these molecules under different conditions. Quantitative and qualitative measurements of large number of cellular metabolites provide a broad view of the biochemical status of an organism that can be used to monitor and assess gene function. Today, metabolomics is widely being used in agriculture for classification of plants, studying phytochemical diversity of medicinal plants, assessment of the changes which occur in the biochemical composition of foods occurring, for example, during the pasteurization of Basmati rice for long-term storage or the boiling for direct consumption. In plant pathology, metabolomics has been mainly used to study plant responses to a wide range of biotic or abiotic stresses including resistance of plants to pathogens and also as a powerful tool for functional genomics studies. Profiling of the transcriptome and proteome has received some criticism due to their inability to predict gene function but profiling of the metabolites is promising as it provides instantaneous large amounts of data from cell physiology. Study of plant genetic resistance is one of the most important applications of metabolomics. Since metabolites are final products of gene expression and all changes in gene expression is reflected in metabolite profiles, hence metabolite profiles produce a more comprehensive understanding of plant defense mechanisms against stresses such as pathogen challenge. On the other hand, breeders are looking for rapid, simple and accurate tools for identifying metabolites associated with resistance as biomarker for screening cultivars resistant to diseases. In addition, understanding resistance mechanisms at the level of metabolome may help breeders for better understanding of resistant gene function and pyramiding suitable resistant gene in elite cultivar. This article is a review of the science, its applications in plant pathology, methods of study metabolites and their administrative problems.
Ali Reza Sholevarfard, Seyed Mohammad Reza Moosavi,
Volume 3, Issue 1 (3-2014)
Abstract
Plant diseases are the most important limiting factors in agricultural production. Currently the major control method of plant diseases is based on the use of chemicals that raises serious concerns about food quality, environmental hazards and development of resistance to agrochemicals. These concerns have increased the need for other alternative disease management techniques. Macro- and micronutrients are normally applied to increase crop production and improve general plant health and quality. They can also increase the disease tolerance or resistance of plants, however there are some opposing reports. Although our knowledge on the impact of mineral nutrients on plant diseases, many other factors that control plant's response and dynamic interactions among plant, environment and pathogen is not sufficient, manipulating soil nutrients through amendment or modification is always an essential part in plant disease control as well as in sustainable agriculture. Mineral nutrients are generally the first and the most important line of defense against plant diseases which affect all parts of the disease triangle. Nutrients can satisfactory decrease diseases, or at least diminish them to a level at which additional control measures are more successful and less expensive. Here we review the most recent data regarding the influence of mineral nutrients on plant disease resistance and tolerance, plant histological or morphological structure and the virulence or capability of pathogens to survive.
