Volk T, Bugbee B, Tubiello F
Department of Biology, New York University 10003, USA.
Life Support Biosph Sci. 1997;4(1-2):49-54.
Phasic control refers to the specification of a series of different environmental conditions during a crop's life cycle, with the goal of optimizing some aspect of productivity. Because of the enormous number of possible scenarios, phasic control is an ideal situation for modeling to provide guidance prior to experiments. Here we use the Ceres-Wheat model, modified for hydroponic growth chambers, to examine temperature effects. We first establish a baseline by running the model at constant temperatures from 10 degrees C to 30 degrees C. Grain yield per day peaks at 15 degrees C at a value that is 25% higher than the yield at the commonly used 23 degrees C. We then show results for phasic control limited to a single shift in temperature and, finally, we examine scenarios that allow each of the five phases of the life cycle to have a different temperature. Results indicate that grain yield might be increased by 15-20% over the best yield at constant temperature, primarily from a boosted harvest index, which has the additional advantage of less waste biomass. Such gains, if achievable, would help optimize food production for life support systems. Experimental work should first verify the relationship between yield and temperature, and then move to selected scenarios of phasic control, based on model predictions.
阶段控制是指在作物生命周期中规定一系列不同的环境条件，目的是优化生产力的某个方面。由于可能的情况数量巨大，阶段控制是建模的理想情况，以便在实验前提供指导。在这里，我们使用针对水培生长室进行修改的Ceres-Wheat模型来研究温度效应。我们首先通过在10摄氏度至30摄氏度的恒定温度下运行模型来建立基线。每日谷物产量在15摄氏度时达到峰值，该值比常用的23摄氏度时的产量高25%。然后，我们展示了仅限于温度单次变化的阶段控制结果，最后，我们研究了生命周期的五个阶段每个阶段都有不同温度的情况。结果表明，谷物产量可能比恒温下的最佳产量提高15%-20%，这主要得益于收获指数的提高，收获指数提高还有减少生物量浪费的额外优势。如果能够实现这些增产，将有助于为生命支持系统优化粮食生产。实验工作应首先验证产量与温度之间的关系，然后根据模型预测转向选定的阶段控制方案。
