Accurate assessments of the yield potential of cassava are needed to analyse yield gaps, define yield targets and set benchmarks for actual yields in Nigeria. This study evaluated the crop model LINTUL-Cassava under assumed potential growth and water-limited conditions in Nigeria. On-farm experiments were conducted at six locations across the three major cassava growing agro-ecologies of Western Africa (Tropical Rainforest – Ogoja and Ikom in Cross River state, Rainforest Transition Savanna – Ekpoma in Edo state and Guinea Savanna – Otukpo in Benue state) during two subsequent seasons (2016 – 2018). Treatments included fertilizer rates calculated to support the assumed potential yields of 90 t fresh storage root yield ha⁻¹ y⁻¹ (equivalent to 32 t DM ha⁻¹, produced in a growing season of 12 months). Light interception (LI) and leaf area index (LAI) were measured each month. The weights of leaves, stems and storage roots were measured at 4 and 8 months after planting and at harvest, and radiation use efficiency (RUE) calculated. The Edo experiment from 2016 was without drought stress and was used to parameterise LINTUL-Cassava and calibrate assimilate partitioning as function of temperature sums. The average fraction of light intercepted during the season was 80 %, with a light extinction coefficient of 0.67 and a RUE of 2.8 g DM MJ⁻¹ intercepted photosynthetically active radiation (IPAR). After calibration, the LINTUL-Cassava model described the crop growth and observed patterns of LAI well in the experiments in Cross River and Edo (2017). Simulated and observed storage root yield at 4 MAP (vegetative period), 8 MAP (mid-season) and at harvest were strongly correlated (R² of 0.92), with a RMSE of 4.93 t DM ha⁻¹. We ascertained that RUE of cassava was much higher than previously observed in Africa, with an average storage root yield of 39 ± 7 t DM ha⁻¹. Consequently, potential yields are greater and yield gaps larger than expected or previously reported. We conclude that the LINTUL-Cassava model can provide an adequate estimate of storage root yield across major cassava growing agroecological zones in Nigeria under rainfed conditions.

需要对木薯的产量潜力进行准确评估，以分析产量差距，确定产量目标并为尼日利亚的实际产量设定基准。这项研究评估了尼日利亚假定的潜在生长和水分受限条件下的作物模型LINTUL-木薯。在西部非洲三个主要木薯种植农业生态系统的六个地点（热带雨林–跨河州的Ogoja和Ikom，雨林过渡的Savanna –江户州的Ekpoma和几内亚Savanna – Benue州的Otukpo）进行了农场试验随后的两个季节（2016年至2018年）。处理方法包括计算肥料剂量，以支持假定的90吨新鲜储藏根产量ha ^-1 y ^-1（相当于32 t DM ha ^-1的潜在产量）。，在12个月的生长季节中产生）。每月测量光拦截（LI）和叶面积指数（LAI）。在种植后4个月和8个月以及收获时测量叶，茎和贮藏根的重量，并计算辐射利用效率（RUE）。从2016年开始的Edo实验没有干旱胁迫，被用于参数化LINTUL-木薯并校准作为温度和函数的同化物分配。在该季节中，平均截获的光线比例为80％，消光系数为0.67，RUE为2.8 g DM MJ ^-1截获的光合有效辐射（IPAR）。校准后，LINTUL-木薯模型在Cross River和Edo（2017）的实验中很好地描述了作物生长并观察到LAI的模式。模拟和观察到的在4 MAP（营养期），8 MAP（季节中期）和收获时的贮藏根产量密切相关（R ²为0.92），RMSE为4.93 t DM ha ^-1。我们确定木薯的RUE值比非洲先前观察到的要高得多，平均储藏根产量为39±7 t DM ha ^-1。因此，潜在产量更高，并且产量差距比预期或先前报道的更大。我们得出的结论是，在雨育条件下，LINTUL-木薯模型可以提供尼日利亚主要木薯生长农业生态区中贮藏根产量的适当估计。