高昼温对日光温室番茄叶片碳水化合物代谢的影响

Changes of Carbohydrate Metabolism of Tomato Leaves under High Temperature in Daytime in Solar Greenhouse

以‘辽园多丽’番茄为试材,以昼温25℃为对照,对植株进行30℃和35℃高昼温处理,探讨在高昼温条件下,叶片碳水化合物含量、蔗糖代谢酶活性以及叶绿体超微结构的变化。结果表明:高昼温尤其是35℃昼温处理,番茄叶片叶绿体超微结构发生改变,短时间内叶绿体中淀粉粒数减少,持续15d后则明显增多,与对照差异显著。高昼温处理的番茄叶片中果糖、葡萄糖和蔗糖含量均降低,昼间温度越高,各糖分含量与对照间差别越明显。在高昼温处理15d时,叶片中酸性转化酶(AI)和中性转化酶活性(NI)降低,而蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性升高,昼温越高,蔗糖代谢相关酶活性与对照的差别越大。高昼温改变了番茄叶片叶绿体的超微结构,并且对糖分的积累与代谢产生影响,最终对植株的生长发育及产量与品质的形成不利,昼温越高,所造成的不利影响越大。

Changes of carbohydrate contents, sucrose-metabolizing enzymes activities and chloroplast ultrastructure in tomato （Lycopersicon esculentum Mill. ） leaves that were treated by 30℃ and 35℃ were studied to investigate the effects of high temperature on carbohydrate metabolism of tomato. Plants were treated by 30℃ and 35℃ in daytime after the 1 st inflorescence effloresced, and plants that under 25℃ were consid- ered as control. Results showed that the chloroplast ultrastructure in high temperature treated plants leaves changed and the number of starch grain in chloroplast decreased firstly then increased obviously after plants had been treated for 15 days, especially those plants that were treated by 35℃. Fructose content, glucose content and sucrose content in treated leaves all decreased compared to control. The higher the temperature in daytime was, the bigger differences between treatments and control were. The activities of acid invertase （AI） and neutral invertase （NI） in treated leaves decreased, but the activities of sucrose synthase （SS） and sucrose phosphate synthase （SPS） increased when plants were treated by high temperature for 15 days. It was maybe the changes of chloroplast ultrastructure, carbohydrate accumulation and metabolism in leaves that made the disadvantage effects on growth and development, yield and quality of tomato. The higher the temperature was, the worse effects they made.