梯度低温对开花结果期番茄的影响

Effect of Gradient Cooling on Tomato during the Flowering and Fruiting Stage

[目的]研究开花结果期梯度降温对番茄生产性状及保护酶活性等生理生化指标的影响,以探讨低温胁迫与番茄开花结果及相关生理生化指标的关系,旨在为确定番茄的寒害温度及相应的栽培措施提供参考。[方法]以广东栽培较广泛的3个番茄生产品种为试验材料,在开花结果期利用梯度降温方式对番茄进行低温处理。[结果]开花结果期梯度低温胁迫导致番茄的生长发育及相关生理生化指标都发生明显变化,结果数、平均单果重和单株产量均减少,尤其是前期产量减少尤为显著;番茄的叶绿素相对含量(SPAD值)降低,且下位叶的SPAD值降低比较显著;番茄叶片的相对电导率升高,Pro含量、MDA含量、可溶性糖浓度增加,SOD和POD活性降低,且处理温度越低,影响越明显。其中,亚蔬2301的耐低温能力最强,红贞女的抗寒能力最弱。[结论]在13℃/3℃(日最高温/日最低温)梯度低温时,番茄并不是过去所认为的5℃时就完全停止生长,因此建议调低番茄的生长极限温度。

[Objective] The aim was to study the effect of gradient cooling on the growth traits,protective enzyme activity and other physicochemical indexes of tomatoes,so as to discuss the relationship between low temperature stress,flowering and fruiting of tomatoes and relevant physicochemical indexes,aiming to provide reference for determining the temperature of cold damage and tomato cultivation measures.[Method] With three widely cultivated tomato varieties as the test material,the low-temperature treatment was conducted on the tomato by using gradient cooling method during its flowering and fruiting stage.[Result] Gradient low-temperature stress during the flowering and fruiting stage led to the obvious change of the growth and physicochemical indexes of tomatoes,the fruiting number,average single fruit weight and single plant yield all increased,especially the yield during the early period;the relative content of tomato chlorophyll（SPAD value） reduced,especially the SPAD value of the lower leaves;relative electrical conductivity of tomato leaves rose,Pro content,MDA content and concentration of soluble sugar increased,SOD and POD activity decreased.The lower the treatment temperature,the more obvious the influence.The low temperature-resistant capacity of Yashu 2301 was the strongest,while the cold-resistant capacity of Hongzhennv was the weakest.[Conclusion] Under 13 ℃/3 ℃（daily maximum temperature/ daily minimum temperature） gradient low temperature,the tomatoes did not stop growing at 5 ℃ as we thought,therefore,it was suggested to lower the growth limit temperature of tomatoes.