The aim of this study was to adapt the CROPGRO model to simulate growth and development processes of Amaranthus spp. under central European conditions. In 2017 and 2018, two field experiments with two amaranth cultivars (grain type, A. hypochondriacus L. Neuer Typ [NT]; fodder type, A. caudatus L. K63 [K63]) were conducted in southern Germany. Based on experimental and literature data, parameter coefficients that drive physiological processes at species, cultivar, and ecotype levels were calibrated to predict the time series experimental observations of various growth and development traits. Statistical evaluation of the model adaptation was performed using root mean square error (RMSE, in variable units, 0 equals perfect fit) and the Willmott agreement index (d-Stat., range from 0 to 1, 1 equals perfect fit). For NT and K63, respectively, the model adaptation led to accurate predictions of canopy height (RMSE, 0.07 and 0.24 m; d-Stat.,0.98 and 0.92), panicle weight (RMSE, 2,034 and 1,153 kg ha^–1; d-Stat., 0.92 and 0.94), panicle harvest index (RMSE, 0.05 and 0.06; d-Stat., 0.99 and 0.96), leaf N concentration (RMSE, 0.38 and 0.40%; d-Stat., 0.94 and 0.92) and aboveground biomass (RMSE, 2,948 and 2,572 kg ha^–1; d-Stat., 0.88 and 0.91). In summary, the CROPGRO model was successfully adapted for Amaranthus spp. The adapted model can be further improved as it is made available for evaluation in different locations and environments including limited soil N supply.

中文翻译：

---

采用 CROPGRO-faba bean 模型模拟苋属植物的生长发育

本研究的目的是调整 CROPGRO 模型来模拟苋属植物的生长和发育过程。在中欧条件下。2017 年和 2018 年，对两种苋菜品种（谷物型，A. hypochondriacus L. Neuer Typ [NT]；饲料型，A. caudatus ）进行了两次田间试验。L. K63 [K63]）在德国南部进行。根据实验和文献数据，对驱动物种、栽培品种和生态型水平生理过程的参数系数进行校准，以预测各种生长发育性状的时间序列实验观察结果。使用均方根误差（RMSE，以可变单位表示，0 等于完美拟合）和 Willmott 一致性指数（d-Stat.，范围从 0 到 1，1 等于完美拟合）对模型适应进行统计评估。对于 NT 和 K63，模型适应导致准确预测冠层高度（RMSE，0.07 和 0.24 m；d-Stat.，0.98 和 0.92），穗重（RMSE，2,034 和 1,153 kg ha ^–1; d-Stat.，0.92 和 0.94），穗收获指数（RMSE，0.05 和 0.06；d-Stat.，0.99 和 0.96），叶片 N 浓度（RMSE，0.38 和 0.40%；d-Stat.，0.94 和 0.92）和地上生物量（RMSE，2,948 和 2,572 kg ha ^–1；d-Stat.，0.88 和 0.91）。总之，CROPGRO 模型成功地适用于Amaranthus spp。适应的模型可以进一步改进，因为它可用于在不同的位置和环境中进行评估，包括有限的土壤 N 供应。