Conventional tillage practices coupled with irrational use of fertilizer in the rice-wheat cropping system (RWCS) often leads to poor productivity, low nutrient use efficiency, and cause environmental pollution. Conservation tillage with surface residue retention in combination with intelligent nutrient management might improve productivity and use efficiency of water as well as nutrients in zero-till direct-seeded rice (ZTDSR). Keeping this in mind, during the kharif season of 2018 and 2019, a trial was carried out at the ICAR-IARI in New Delhi to investigate the varying nutrient management approaches following a precise manner in DSR. The treatments consisted of soil-test-based NPK (STB-NPK) and Nutrient Expert^® (+LCC_N) based NPK (NE-NPK) applications, Fertilizer applied at the recommended dose (RDF) [120-60-40 kg/ha NPK], the state recommended NPK (110-50-40 kg/ha) and omission plot technique of NPK [i.e., STB (N₀PK, NP₀K & NPK₀); SR (N₀PK, NP₀K & NPK₀) and NE-(N₀PK, NP₀K & NPK₀)]. The results indicated that STB NPK application led to a 12% higher grain yield over RDF. However, NE-NPK resulted in a 7% and 35% increase in N (AEN) agronomic efficiency and P (AEP) over the STB-NPK application respectively. In contrast, AE_k was 24% higher in STB-NPK over NE-NPK treatment. The comparison of two years’ results that the first year performed better than the succeeding year in these respect (productivity and AE) except in the case of AE_k. The N₂O emission in NE-NPK treatment was also significantly reduced (49%) over the control (no N). STB-NPK treatment also improved profitability by 22% over RDF. Precision nutrient management (PNM) increased the crop yield, income, and use efficiency of nutrients and water and reduced greenhouse gas (GHG) emissions of DSR in Southeast Asia.

Imbalanced use (form, quantity, and ratio) of nitrogen fertilization can result in decreased grain yields and increased nitrogen loss, leading to adverse effects on overall environmental quality. Globally, limited empirical research has been conducted on the comprehensive effects of different levels of N that can significantly influence wheat agronomic and genotypic traits. Therefore, this study aimed to evaluate wheat genotypes for two consecutive years (2020–2021 and 2021–2022) under different N fertilization treatments: N0 (native N, without external application of N), N75 (½ of the recommended dose of N), and N150 (recommended dose of N). The study findings revealed that ‘HD 3249’ and ‘HD 3117’ were the top-performing genotypes in terms of grain yield (5.3 t ha⁻¹; 5.0 t ha⁻¹), straw yield (6.9 t ha⁻¹; 6.7 t ha⁻¹), biological yield (12.2 t ha⁻¹; 11.8 t ha⁻¹), and harvest index (42.9%; 42.4%). In particular, the application of N75 and N150 increased grain yields by 142.6% and 61.3%, respectively; straw yields by 72.3%; and by 110.6% over N0. Furthermore, N levels (N75 and 150) significantly increased the higher concentration of N in grain (23.1% and 33%) and straw (21.1% and 29.8%); N uptake in grain (70.2 and 104.2) and straw (64.8 and 41.5); and total N uptake (68.8% and 101.4%) than N0, respectively. Additionally, correlation analysis revealed that there were positive correlations between yields, harvest index as well as N concentration and uptake. This study identified the two elite genotypes, ‘HD 3249’ and ‘HD 3117’, with N150 splits giving a better response, which can be used as selection criteria for developing wheat varieties that are more efficient in using nitrogen, leading to high yields and N uptake.

The growth of agricultural sectors can be maintained by increasing crop productivity through soil, water, and nutrient management. The most important management practice is nutrient management, which is supported by the effective use of nano-technology, especially nano-fertilizers. It is well known that nano-fertilizers are nutrient carriers of nano dimensions ranging from 30 to 40 nm (10−9 m or one-billionth of a meter). Due to their high surface area, they can hold abundant nutrients ions and release them slowly and steadily, commensurate with crop demand. Nano-fertilizers are easily uptaken and assimilated by the plants because of their ease of solubility, stability, controlled release in time, and easy mode of delivery and disposal. Due to nano fertilizers characteristics, different commercial products are available in the market, namely Nanogro, Geohumus, NanoGreen, and Lithovit High Yield fertilizer, which can be demonstrated among the farmers for increasing agricultural performance through soil and nutrient management. Besides, nano-fertilizer has good criteria like disease resistance properties. Nanoparticles of ZnO, CuO, and MgO can kill different fungal infections of crop plants. Though nano-fertilizers can be beneficial for improving agricultural performance, it has a detrimental effect on soil microflora, fauna, animals, and humans. It is associated with several diseases or hazards like high blood pressure, blood clots, stroke, arrhythmia, heart disease, etc. Nano-fertilizer also improves the yield of several field crops like pearl millet, wheat, pomegranate, onion, tomato, soybean, and vegetable crops like spinach and cucumber. Nano fertilizers also have sound capabilities to find the solution against the issues arising in modern agriculture due to conventional fertilizer application. Thus, nano-fertilizer has the potential to improve the yield of several field crops.

A field experiment was conducted in a split-plot design during the rainy (kharif) seasons of 2015 and 2016 at Varanasi, Uttar Pradesh, to evaluate the relative performance of different fertility levels (60%, 80% and 100% of recommended dose of fertilizer) and foliar spray of cow urine (control, 50%, 75% and 100% concentration) on growth, yield and economics of BPT 5204 rice (Oryza sativa L.). The recommended dose of fertilizer (RDF) for rice was 120, 60, 60 and 25 kg/ha of N, P O , K O and ZnSO respectively. Various growth parameters and yield 2 5 2 4 levels of rice showed significant variation during the experimental years under different levels of fertility and cow urine foliar spray. Among the fertility levels, 80% and 100% RDF significantly improved grain yields of rice over 60% RDF by 6.8% and 14.8% respectively. Applications of cow urine (4 foliar sprays) were positively correlated with various growth parameters, yield attributes and yield levels of rice. Increments in grain yields of rice were to the tune of 4.4%, 4.4% and 10% over control for 50%, 75% and 100% cow urine concentration respectively. In terms of economics, the highest net returns and benefit: cost ratios were obtained from 100% RDF and 100% cow urine spray during both the years. Among the fertilizer treatments, 100% RDF recorded up to 18.2% higher net re- turns over 60% RDF, which was 16.4% over the control in case of 100% cow urine spray.