Research shows that increasing population growth will cause an intensification of food scarcity. Therefore, plant disease management practices must be improved to mitigate the damaging effects of already induced yield loss. Because pests and diseases have varying effects on plants, however, control practices must be catered to the specific location, crop, and type of pest. With climatic and atmospheric changes, plant disease management strategies have to adjust in accordance with these new conditions. Some ways in which temperature change and atmospheric change may affect the relationship between plants and pathogens are by altering the host plant’s susceptibility and by reducing the pathogenic resistance, as well as other changes. Juroszek et al. (2011) conducted a review on disease management practices and researched the ways in which these tactics will have to be altered in accordance with climate change. The authors specifically looked at fungal plant pathogens in agriculture<!–[if supportFields]> XE “agriculture” <![endif]–><!–[if supportFields]><![endif]–> and horticulture. —Daniela Hernandez
Juroszek, P., von Tiedemann, A., 2011. Potential Strategies and future requirements for plant disease management under a changing climate. Plant Pathology 60, 100–112.
The authors researched some possible agronomic practices that can mitigate the impact of plant diseases. Generally speaking, planting a diverse set of crops may significantly decrease the threat of plant disease associated with monocultures. The authors additionally point at the importance of crop rotation as a disease management strategy, especially under climate change. Other strategies include changing the harvest date, to avoid pathogen infection, as well as planting cultivar mixtures and intercropping. The benefit of the latter two strategies is that they have the potential of slowing down the rate of epidemics. At the same time, however, the intercrop implemented can outcompete the crop being managed, thus reducing yield. The authors suggest more research be conducted to investigate the extent of these effects.
Juroszek et al. also researched the implementation of resistant crops as a disease management strategy under the climate change criteria. According to the authors, some of the factors that need to be taken into consideration when looking at disease resistance and the implementation of possible resistant crops are temperature, “…leaf wetness, nutrient status (e.g. nitrogen<!–[if supportFields]> XE “nitrogen” <![endif]–><!–[if supportFields]><![endif]–> fixation<!–[if supportFields]> XE “nitrogen fixation” <![endif]–><!–[if supportFields]><![endif]–>), soil type and availability of water (105).” Research suggests that increased CO2 levels can lead to acceleration in the pathogen evolution for increased aggressiveness. Juroszek et al., however, resist making any ultimate correlation, as much more research is needed.
The researchers additionally looked at fungicides as possible disease management strategies under climate change. Studies show that increasing CO2 will require an additional amount of fungicides to those plants negatively affected by this change in atmospheric condition. Other studies, however, show how increasing temperatures reduce the efficiency of certain fungicides against pathogens. An increase in CO2and temperature can also lead to morphological changes to the plant, which can ultimately reduce the effectiveness of the plant protection products (PPPs). The authors suggest that optimizing the time at which the PPPs are used can help increase this effectiveness. The ideal fungicide application will be dependent on the specific disease and crop, since climate and atmospheric change might alter the favorability of the disease in a positive or negative way.
Another type of disease management practice the authors analyzed was the application of biological control<!–[if supportFields]> XE “biological control” <![endif]–><!–[if supportFields]><![endif]–> agents (BCAs). The adoption of this technique is also dependent on the specific antagonistic organism’s reaction to temperature and atmospheric change. Some studies imply that pathogens may be favored under these changes, while other studies suggest the antagonistic organism might be favored.
Adopting integrated pest management (IPM) as a management practice was also researched in this review. IPM is a preventative strategy whose main goal is long-term effectiveness of preventing plant disease. It uses a combination of other strategies such as “…biological control<!–[if supportFields]> XE “biological control”<![endif]–><!–[if supportFields]><![endif]–>, use of resistant cultivars, habitat management and cultural practices (108).” Juroszek et al. recommend models be used to predict the long-term consequences in order to adopt the ideal IPM.
The authors ultimately suggest that the ideal disease management strategy must be implemented given the specific plant, pathogen, and environmental factors. They find that disease-forecasting models will be key in analyzing this based on the effect of climate and atmospheric change on plant disease instance and severity.