Sarkar Sayantika, Upadhyay Pravin Kumar, Dey Abir, Ekka Utpal, Rathore Sanjay Singh, Shekhawat Kapila, Yeasin Md, Singh Rajiv Kumar, Babu Subhash, Dass Anchal, Mitran Tarik, Sharma Navin Kumar, Kumar Atul, Singh Satendra, Singh Vinod Kumar
ICAR-Indian Agricultural Research Institute, New Delhi, India.
ICAR-Indian Agricultural Statistics Research Institute, New Delhi, India.
PLoS One. 2025 Apr 2;20(4):e0318678. doi: 10.1371/journal.pone.0318678. eCollection 2025.
Efficient nitrogen (N) management is critical for sustaining high maize yields while minimizing environmental impacts, as conventional practices often lead to N losses, greenhouse gas emissions, and reduced eco-efficiency. To address these challenges, the "Pusa N Doctor" app was developed using dark green colour index (DGCI) for precision N management in maize. The app was further validated in experiment conducted with three N rates- 0 kg/ha (N0PK), 50 kg/ha (N0PK), and 75 kg/ha (N75PK) as basal, along with two splits of N at 35 and 45 DAS as per app (N50PK+App and N75PK+App) and GSTM (N50PK + GSTM and N75PK+GSTM). The plant height, leaf area index, and plant N concentration was highest in N75PK+App. The highest crop growth rate between 0-30 DAS was observed in the N75PK+App treatment (9.97 g/m²/day). Conversely, the maximum relative growth rate between 30-60 DAS was in the N50PK+App, while the lowest was in N75PK+App. The highest harvest index of 35.13% was in N50PK+App. Except for N75PK+App and recommended dose of fertilizer (RDF), the partial N balance was close to 1, with a minimum value of 0.87 in N75PK+App. The lowest virtual N was in N50PK+App (0.45), while in N75PK+App it was 2.16 times higher than RDF. All N fertilized treatments except N50PK+App witnessed increased cost of cultivation over RDF. N50PK+App had 29.5% lower GHGI of N2O, with 11.6% and 13.3% higher energy and GHG-based eco-efficiency respectively than RDF. Thus, applying 50 kg N as basal along with its 2 splitting as per Pusa N Doctor, optimizes maize-growth, N use efficiency, eco-efficiency, and reduces GHG emissions.
高效的氮（N）管理对于维持玉米高产同时将环境影响降至最低至关重要，因为传统做法往往会导致氮素损失、温室气体排放和生态效率降低。为应对这些挑战，开发了 “普萨氮博士” 应用程序，利用深绿色叶面积指数（DGCI）对玉米进行精准氮管理。该应用程序在一项实验中得到进一步验证，实验设置了三种氮肥用量作为基肥，分别为0千克/公顷（N0PK）、50千克/公顷（N50PK）和75千克/公顷（N75PK），并根据该应用程序在35天和45天分别进行两次氮肥追施（N50PK + App和N75PK + App）以及常规施肥管理（N50PK + GSTM和N75PK + GSTM）。N75PK + App处理的株高、叶面积指数和植株氮浓度最高。在0 - 30天期间，N75PK + App处理的作物生长速率最高（9.97克/平方米/天）。相反，在30 - 60天期间，最大相对生长速率出现在N50PK + App处理，而最低的是在N75PK + App处理。N50PK + App处理的收获指数最高，为35.13%。除了N75PK + App处理和推荐施肥量（RDF）外，部分氮平衡接近1，N75PK + App处理的最小值为0.87。N50PK + App处理的虚拟氮最低（0.45），而在N75PK + App处理中，它比RDF高2.16倍。除了N50PK + App处理外，所有施氮处理的种植成本均高于RDF。N50PK + App处理的N2O温室气体排放强度比RDF低29.5%，基于能量和温室气体的生态效率分别比RDF高11.6%和13.3%。因此，按照 “普萨氮博士” 的建议，基肥施用50千克氮并进行两次追肥，可优化玉米生长、氮利用效率和生态效率，并减少温室气体排放。
