How damping off diseases cause damage in tomato and how it can be controlled?

The fungus attack usually starts on the germinating seed, and further spread to the hypocotyl, basal stem, and developing tap-root. It can be controlled by drenching the nursery bed with 5 litre formalin dissolved in 100 litres of water 15 days before sowing. Before sowing, hot water treatment of seed at 52°C for 30 minutes should be done. Spray mancozeb (2.5g /L), carbendazim (1g /L) on nursery seedlings.