Abstract:

To enhance adaptability of tomatoes cultivated in the north to the sub-low nighttime temperature in early spring, ‘Liaoyuanduoli’ (cold-resistant strains) and ‘Lijiadafen’ (cold-sensitive strains) tomato strains seedlings were chose as experimental material. The effects of exogenous acetyl salicylic acid (ASA) on tomato seedlings at sub-low nighttime temperature of 9℃ were observed by determining the malondialdeyde content, conductivity and proline concent of tomato leaves, which was carried out by spraying ASA of different concentrations on the leaves when the tomato seedlings was in the phase of two leaves and one heart. Exogenous acetyl salicylic acid of ‘Liaoyuanduoli’ tomato strains 40 mg/L and ‘Lijiadafen’ tomato strains 120 mg/L may help to resist the sub-low temperature, protecting tomato seedlings from threatens of low temperature. Therefore, when the tomato seedlings are in the phase of two leaves and one heart, the spraying of acetyl salicylic acid of a optimal concentration can reduce the damage of sub-low nighttime temperature to tomato seedings, improving the cold-resistance of tomato seedlings.