effect of sodium hypochlorite on germination of lettuce seed at high temperature

Investigations into the effects of treatment with sodium hypochlorite solution on high-temperature germination of lettuce seed are described. A 2 h treatment in a solution with 10% available chlorine enabled up to c. 70% of seeds to germinate at 35 °C, without impairing germination and normal seedling development at 20 °C. A 10 min rinse in 0.01 N HCI following such treatment enhanced its effect and treated seeds retained their ability to germinate at high temperature for at least 18 months. Seedling development at 20 °C following treatment was influenced by treatment temperature and batch of hypochlorite solution. Emergence from compost in a cycling (30/15 °C) temperature regime was improved in three out of five cultivars tested, and there were indications that hypochlorite treatment enabled one of the other cultivars to escape induced thermodormancy.