Lescourret Françoise, Génard Michel
INRA, Plantes et Systèmes de culture Horticoles, Domaine Saint-Paul, site Agroparc, 84914 Avignon cedex 9, France.
Tree Physiol. 2005 Oct;25(10):1303-15. doi: 10.1093/treephys/25.10.1303.
A virtual fruit model simulating seasonal changes in several peach (Prunus persica (L.) Batsch) fruit quality traits during the final growth stage is presented. The quality traits considered are fruit size, the proportion of total fruit mass consisting of fruit flesh, dry matter content of the flesh and the concentrations of sucrose, glucose, fructose and sorbitol in the flesh, which are used to calculate a sweetness index. The virtual peach fruit model was developed by adapting and integrating three existing process-based models describing fruit dry mass growth, fruit fresh mass growth and sugar accumulation in the flesh into one complex system. Data sets of peach fruit growth and quality obtained from one field site over several years were used to estimate parameters and evaluate the virtual peach fruit model. Output from the model showed good agreement with the field data. Insight into the complex nature of the virtual peach fruit model, i.e., its ability to show emergent properties, was accomplished by conducting a series of theoretical experiments. The virtual peach fruit model was shown to be sensitive to management and environmental factors (leaf:fruit ratio, stem water potential and, to a lesser extent, weather). Its ability to generate simple laws relating to physiological variables and quality parameters was also demonstrated. Finally, the virtual peach fruit model was able to reveal complex behaviors resulting from changes in water potentials or leaf:fruit ratios over time.
本文提出了一个虚拟果实模型，该模型可模拟桃（Prunus persica (L.) Batsch）果实生长后期几个果实品质性状的季节性变化。所考虑的品质性状包括果实大小、果肉占果实总质量的比例、果肉干物质含量以及果肉中蔗糖、葡萄糖、果糖和山梨醇的浓度，这些用于计算甜度指数。虚拟桃果实模型是通过将三个现有的基于过程的模型（分别描述果实干物质生长、果实鲜重生长和果肉中糖分积累）进行改编和整合，形成一个复杂系统而开发的。利用多年来从一个田间地点获得的桃果实生长和品质数据集来估计参数并评估虚拟桃果实模型。模型输出与田间数据显示出良好的一致性。通过进行一系列理论实验，深入了解了虚拟桃果实模型的复杂性质，即其展现涌现特性的能力。结果表明，虚拟桃果实模型对管理和环境因素（叶果比、茎水势以及在较小程度上对天气）敏感。还证明了其生成与生理变量和品质参数相关的简单规律的能力。最后，虚拟桃果实模型能够揭示由于水势或叶果比随时间变化而产生的复杂行为。
