Intermediate wheatgrass (Thinopyrum intermedium (Host) Barkworth & D.R. Dewey) is being developed for use as a new perennial grain crop through breeding and agronomic research. However, progress has been hampered by lack of understanding of environmental requirements for flowering and grain production. Therefore, we developed a phenology model for IWG adapted from the STICS soil-crop model. The model was compliant with experimental results (relative root mean square error = 0.03). The optimal vernalizing temperature was between 4 and 5°C, optimal daylength between 13 and 14h, while daylength below 11h slowed reproductive development. Vernalization requirement was found to be a constraining inductive process. Including a photoperiod limitation to the model with temperature improved its ability to predict induction at various latitudes. Therefore, timing and duration of vegetative vs. reproductive growth may differ between environments and change reproductive tiller elongation earliness, weed competitiveness, management timing, and stress conditions during phases critical to grain yield. Accurate phenology models will enable optimal field management and inform future breeding strategies. However, plasticity may lead to divergent ideotypes under various agroecosystems.

中级小麦草（Thinopyrum intermedium（主持人）Barkworth＆DR Dewey）正在通过育种和农艺研究被开发为一种新的多年生谷物。然而，由于对开花和谷物生产的环境要求缺乏了解，阻碍了进展。因此，我们根据STICS土壤作物模型开发了IWG的物候模型。该模型符合实验结果（相对均方根误差= 0.03）。最佳春化温度在4至5°C之间，最佳日间长度在13至14h之间，而日间长度低于11h则减慢了生殖发育。发现春化要求是一个制约性的归纳过程。在温度范围内将光周期限制包括在内，可以提高模型预测各种纬度感应的能力。因此，营养与营养的时间和持续时间。各个环境之间的生殖生长可能会有所不同，并且在对谷物产量至关重要的阶段中，会改变生殖分long伸长的早期性，杂草竞争力，管理时机和胁迫条件。准确的物候模型将使最佳田间管理和未来的育种策略成为可能。但是，在各种农业生态系统下，可塑性可能导致不同的表型。