Environment-Pathogen Interaction in Plant Diseases

Abstract

nvironment is an important aspect of plant ecology and global environmental change is of major concern that is caused by natural and human activities which alter greenhouse gas concentrations in the atmosphere. The increase in concentration of greenhouse gases is foreseen to continue to raise average global temperature. Elevated concentration of carbon dioxide with increased temperature influences the plant-disease interactions. The environment has an influence over the development as well as temporal and spatial dissemination of plant diseases. The result of change in environment can either be favorable, non favorable or impartial, as these changes can either lessen, expand or have no influence on diseases as each disease may be attributed differently to these variations in accordance to an area or time of year. Variation in environmental conditions is said to be influencing plants in natural ecosystems all around the world and change in climate directly impacts crops, along with their synergy in accordance with the microbial population. The important elements governing magnification and spread of plant diseases are temperature, moisture, light and carbon dioxide concentration. Environment change causes a significant impact on germination, reproduction, sporulation, spore dispersal, along with perforation by pathogens as a vulnerable host will not be invaded by a pernicious pathogen if the environmental conditions are not facilitative for disease. The environment influences all life stages of host as well as that of a pathogen and as a result induces an opposition to various pathosystems. Resistance mechanisms of plants, including effector-triggered immunity (ETI), pattern-triggered immunity (PTI) and defence network of hormones, are particularly influenced by environmental elements. Pathogenic virulence mechanisms like fabrication of virulence proteins and toxins, and also spore germination and survival are governed by factors such as atmospheric carbon dioxide, temperature and humidity. A large number of in-vitro experiments to understand interactions between plants and pathogens rely on predetermined pathosystems by making use of ascertained environmental conditions which take into consideration relatively small part of vital plant–pathogen–environment interactions occurring in natural ecosystem. Thus, there is a need to research effectiveness of disease management strategies that is, to assess current management strategies to understand multifaceted nature of environment-pathogen interactions for production of crops that are irrepressible to environment change.