昼夜温差对番茄果实品质动态变化的影响及模拟

为了研究昼夜温差对番茄果实膨大-成熟期各阶段果实品质动态变化的影响,并构建昼夜温差对果实品质影响的模拟模型,以番茄品种"金冠5号"为试验材料,在人工气候箱对坐果后的番茄植株进行昼夜温差处理,设置25℃日平均温度下5个昼夜温差(DIF)水平,即-18℃(16℃/34℃,昼温/夜温)、-12℃(19℃/31℃)、0℃(25℃/25℃)、+12℃(31℃/19℃)、+18℃(34℃/16℃),测定各处理下番茄果实品质指标。结果表明:正昼夜温差可提高番茄果实营养成分含量和品质,而负昼夜温差使其降低。正昼夜温差使可溶性糖、糖酸比、可溶性蛋白、Vc含量增加,+12℃DIF处理下各营养品质含量高于+18℃DIF下,而负昼夜温差使其降低,且随负昼夜温差的增大而降低。有机酸含量在正昼夜温差下减少,而在负昼夜温差下增加。番茄红素含量在+12℃DIF下上升,而在+18℃DIF和负昼夜温差下降低。不同昼夜温差处理下,可溶性糖、可溶性蛋白含量均与辐热积呈Logistic模型关系,通过拟合昼夜温差值与Logistic模型参数的数量关系,得到昼夜温差对可溶性糖、可溶性蛋白动态变化影响的模拟模型。有机酸、Vc含量均与辐热积呈二次多项式关系,通过拟合昼夜温差与二次多项式模型参数的数量关系,得到昼夜温差对有机酸、Vc动态变化影响的模拟模型。检验结果表明,模型模拟效果良好。

Effect of Day and Night Temperature Difference on Fruit Quality of Tomato and its Simulation Models

In order to investigate the effect of difference between day and night temperature (DIF) on fruit quality of tomato during fruit stage and establish stimulation model for influence of DIF on fruit quality, three experiments were conducted in Jinguan 5 plants after setting fruit in climate chambers. Five day/night temperature regimes 16℃/34℃, 19℃/31℃, 25℃/25℃, 31℃/19℃ and 34℃/16℃ with respective DIF of-18℃,-12℃, 0℃, +12℃ and +18℃ at a common 25℃ mean daily temperature were used. The fruit quality indices under all DIF treatments were determined. The results showed that fruit quality of tomato was promoted under positive DIF, while inhibited under negative DIF. The soluble sugar content, sugar to acid ratio, soluble protein content, vitamin C were increased under positive DIF, while decreased under negative DIF. They were larger under +12℃ DIF than that of +18℃ DIF. On the contrary, organic acid was decreased under positive DIF but increased under positive negative DIF. Lycopene content was increased under +12℃ DIF, but decreased under +18℃ DIF and negative DIF. Under different DIF, the relationship between fruit quality indexes such as soluble sugar, soluble protein, and thermal effectiveness and PAR (TEP) were in Logistic model. By fitting the numerical relationship between DIF and Logistic model parameters, the simulation models of the impact of DIF on soluble sugar, sucrose, soluble protein content of tomato fruit were established. The relationship between fruit quality indices such as organic acid and vitamin C and TEP were in quadratic polynomial model. By fitting the numerical relationship between DIF and quadratic polynomial model parameters, the simulation models of the impact of DIF on organic acid and vitamin C content of tomato fruit were established. The simulation effect of the models proved to be good by independent experiment data.