Comparative Evaluation of Nutrient Balance in Sugarcane Using DRIS and CND Models: A Two-Year Study Field in Shuaibiyeh, Southwest Iran

Nutrient imbalance is a significant constraint in achieving optimal crop productivity. The availability of nutrients throughout the crop cycle is crucial for normal plant development, making nutrient management a key factor in maximizing yield. This study evaluated the nutrient balance status of sugarcane (Saccharum officinarum L.) using the Diagnostic and Recommendation Integrated System (DRIS) and Compositional Nutrient Diagnosis (CND) models over a two-year field experiment (2023–2024). Leaf samples were collected at various phenological stages from commercial sugarcane fields in Shuaibiyeh, Khuzestan Province (southwest Iran), and analyzed for macro- and micronutrient contents. DRIS and CND indices were computed to identify nutrient imbalances and determine priority elements for correction. Results indicated that the CND model demonstrated a stronger correlation with yield (R² > 0.9) compared to DRIS. According to the CND indices in low-yielding fields, the priority order of nutrient deficiencies was: Zn > Mn > Mg > Fe > Ca > K > N > Cu > P. In contrast, the DRIS method classified nutrient priorities into high and low consumption categories, identifying the order as: Zn > K > Mg > Mn > Ca > N > Fe > Cu > P. Both diagnostic methods consistently identified zinc as the most limiting nutrient, while phosphorus frequently appeared in excess. These findings highlight the superior diagnostic capability of the CND model and underscore the need for balanced nutrient management strategies to enhance yield and promote sustainability in sugarcane agroecosystems.

养分失衡是制约作物实现最佳生产力的关键限制因素。作物全生育期内的养分供给对植株正常生长发育至关重要，因此养分管理是实现产量最大化的核心环节。本研究依托2023—2024年为期两年的田间试验，采用诊断与推荐综合系统（Diagnostic and Recommendation Integrated System, DRIS）以及养分组成诊断（Compositional Nutrient Diagnosis, CND）模型，对甘蔗（Saccharum officinarum L.）的养分平衡状况进行了评估。研究人员从伊朗西南部胡齐斯坦省舒巴耶赫的商业甘蔗种植园的不同物候期采集叶片样品，并对其中的大量元素与微量元素含量开展检测分析。通过计算DRIS与CND指数，明确养分失衡情况并确定需优先矫正的养分元素。结果显示，相较于DRIS模型，CND模型与产量的相关性更强（决定系数R²>0.9）。根据低产田的CND指数结果，养分缺乏的优先矫正顺序为：锌（Zn）>锰（Mn）>镁（Mg）>铁（Fe）>钙（Ca）>钾（K）>氮（N）>铜（Cu）>磷（P）。与之相对，DRIS方法将养分优先级划分为高消耗与低消耗两类，其确定的优先矫正顺序为：锌（Zn）>钾（K）>镁（Mg）>锰（Mn）>钙（Ca）>氮（N）>铁（Fe）>铜（Cu）>磷（P）。两种诊断方法均一致认定锌是最主要的限制性养分，而磷则常表现为过量富集。本研究结果凸显了CND模型更优异的诊断性能，同时强调了需制定平衡的养分管理策略，以提升甘蔗农田生态系统的产量并促进其可持续发展。