Effects of Short-term Low Night Temperature on the Resistant Physiological Index of Domesticated Tomato and Wild Relative

Chilling-sensitive tomato Money Maker and chilling-tolerant wild tomato LA1777 were studied,and effects of low night temperature of 15,9,6℃ and recovery on the resistant physiological index of tomato fruits were investigated.The results showed that soluble sugar,proline content and POD activities increased in tomatoes LA1777 and Money Maker after low night temeperature treated,but the variation in LA1777 is greater.SOD activity in LA1777 was lower than control,CAT activities was higher than control,otherwise,the SOD activity in Money Maker was higher than control,CAT activities was lower than control.The increase of MDA content in Money Maker was significantly greater than control,while no significant change in LA1777.These results demonstrate that the two types of tomato fruits exerted higher level of soluble sugar and proline content to chilling stress under short-time low temperature,the chilling-tolerant tomato exerted higher level of POD and CAT activities to chilling stress,while the chilling-sensitive tomato exerted higher level of SOD activity,the enhanced membrane lipid peroxidation in the chilling-tolerant tomato fruits is lower.