The factors which are responsible for huge yield loss of potato are applied improper management strategies and pathogen behavior. Management strategies include forecasting, cultural, biological, varietal and chemical management. Forecasting is the better option for management of late blight, if accurately forecasted and promptly information reaches to the endusers. Infected potato tubers cause the primary sources of infection in next season. The cultural practices will also helpful in reducing inoculum load and managing the disease. The host resistance is the best option for management of late blight disease. However, due to very divers’ virulence nature of P. infestans; the resistance of the varieties is wiped out within a decade. Several fungicides including contact, systemic and translaminar have been evaluated from time to time; however, the pathogen has shown a remarkable capacity for change with respect to host genotype and fungicides. Nowadays biological control is gaining importance as it is eco-friendly
Several management strategies have been developed for late blight of potato and adopted by the farmers/potato growers as per availability of the resources. Among them, chemicals, host resistant, biological control, and cultural control are in use.
The cultural practices, includes inoculum free seeds and planting materials, crop and field sanitation and adjustment of crop cultures. Cultural practices classified into three categories: i. Practices, which are usually applied for agriculture purposes not directly connected with crop protection, such as fertilization and irrigation. They may or may not have a positive or a negative side effect on disease incidence or severity, ii. Practices that are used completely for disease control, such as sanitation and flooding and iii. Practices, which are used for both agricultural purposes and for disease control, such as crop rotation, grafting and composting
Host resistance is the best option for management of late blight of potato and it is eco-friendly in nature. Generally, after a decade, resistant level of the cultivars is being defeated, due to matching of new virulence genes. Development of resistant cultivars and exploitation of screening methodology has played an important role in the management of late blight
The late blight pathogen is highly dependent on environmental factors like temperature, relative humidity and leaf wetness etc. for causing late blight disease. Therefore, various forecasting models had been developed for forecasting late blight disease.
The disease can be managed with a timely application of fungicide, though epidemics can occur rapidly once crops are infected. Given that the oospores have thickened walls and are able to persist in the soil for several seasons, the disease can be difficult to eradicate.