Pythium-induced damping-off disease and its management in tomato (Solanum lycopersicum L.): A review

A. Adhikari, D. Oli, P. Poudel, P. B. Magar, S. Pandit, A. Pokhrel, S.B. Gurung, J. Shrestha

1Himalayan College of Agricultural Sciences and Technology, Purbanchal University, Kathmandu, Nepal
2Montana State University, Department of Plant Sciences & Plant Pathology, Bozeman, USA
3Nepal Agricultural Research Council, National Plant Pathology Research Centre, Khumaltar, Lalitpur, Nepal
4Nepal Agricultural Research Council, National Maize Research Program, Rampur, Chitwan, Nepal
5Nepal Agricultural Research Council, National Plant Breeding and Genetics Research Centre, Khumaltar, Lalitpur, Nepal

(Manuscript received 21 November 2022; accepted for publication 15 February 2024)

Abstract. Pythium-induced damping-off is a disease that causes the decay of germinating seeds and young seedlings of tomato, and it is one of the most significant yield constraints for farmers in both nurseries and fields. Conventional fungicides are widely used to manage this disease, leading to two major consequences. Excessive fungicide use not only endangers human health and raises environmental concerns but also promotes the emergence of pesticide-resistant microorganisms in the environment. Consequently, there is growing interest in developing long-term damping-off management strategies that minimize reliance on conventional pesticides. To facilitate decision-making, a better understanding of pathogen biology and disease epidemiology is required. The major findings of this review works are as follows: i) Pythium-induced damping-off is an emerging disease that affects tomatoes in nurseries and fields and causes economic loss; ii) Epidemiological factors identified as most favorable for disease development include high soil moisture (70% or higher), low light, and moderate soil temperatures around 25°C.; and iii) Considerable research efforts in recent years have focused on developing bio-control solutions for damping-off, showing promising future prospects. To ensure higher tomato production, researchers and growers should manage Pythium-induced damping off in their fields. This review serves as a useful guide for the management of this disease.