From Pathogen to Protection: Integrated Disease Management Strategies for Tomato Late Blight

Tomatoes, a vital global crop valued for their nutritional benefits and culinary versatility, are under significant threat from various pathogens, particularly Phytophthora infestans, which causes Late Blight (LB). Originally from South America, tomatoes have become a staple crop worldwide. However, diseases, such as LB, can devastate yields by as much as 80%, reminiscent of its role in the historic Irish Potato Famine. Symptoms on tomato foliage and fruits characterized by rapid infection and destruction under humid conditions with visible white sporulation. Survival between crops occurs through infected tomato fruit, producing airborne sporangia that infect healthy foliage. Environmental factors like temperature (15-20 °C) and humidity strongly influence disease progression. Cloudy weather supports late blight due to reduced UV radiation, crucial for sporangia viability. Integrated Disease Management (IDM) presents the most sustainable approach to controlling LB. The objective of this review article was to overview research achievements of tomato late blight management, identifies gaps and suggests future research directions in the area of tomato late blight management research and development. It combines cultural practices, fungicide applications, and the use of resistant varieties. Non-pesticide management options such as cultural and host resistance against the test pathogen did not reach the smallholder vegetable farmers due to limited effort made by the research-extension system. Cultural methods like crop rotation and sanitation are pivotal in reducing pathogen reservoirs, while resistant varieties offer primary defense against Phytophthora infestans. Biological control methods, such as using biocontrol agents and plant extracts, hold promise for environmentally friendly disease suppression. Nonetheless, optimizing their effectiveness under severe disease pressure remains a challenge. Chemical control through fungicides like ridomil remains crucial for immediate disease suppression, underscoring the ongoing necessity for balanced, integrated strategies to mitigate LB’s impact on global tomato production. In this review use of various management options are important to reduce epidemiology of late blight. Future research should focus on developing an IDM with no or minimum input of chemical pesticides. Continuous research and application of these strategies are critical for sustaining tomato yields and ensuring food security amidst evolving environmental and pathogenic challenges.