**2.7 Integrated nutrient management**

Integrated nutrient management (INM) plays a crucial role in optimizing maize production by adopting a holistic approach to meet crop nutrient requirements efficiently [2, 3]. INM involves the integration of various nutrient sources, including organic manures, inorganic fertilizers, biofertilizers, and crop residues, to enhance soil fertility and promote sustainable crop growth. Organic manures, such as farmyard manure (FYM) and compost, are valuable sources of macro and micronutrients, as well as organic matter, which improve soil structure and nutrient availability. Incorporating organic manures into the soil at recommended rates not only supplies essential nutrients but also enhances soil health and microbial activity. Inorganic fertilizers, such as nitrogen, phosphorus, and potassium fertilizers, are often used in combination with organic manures to supplement nutrient deficiencies and achieve balanced nutrition. Biofertilizers, including nitrogen-fixing bacteria, phosphatesolubilizing bacteria, and mycorrhizal fungi, can be applied either as seed inoculants or through soil application to enhance nutrient uptake and improve soil nutrient cycling [51]. Additionally, incorporating crop residues into the soil as green manure helps enhance soil organic matter content and nutrient availability. INM practices also include precision nutrient management based on soil testing to determine nutrient

#### *Nutrient Management of Maize DOI: http://dx.doi.org/10.5772/intechopen.112484*

deficiencies and adjust fertilizer application rates accordingly. Adopting balanced fertilization practices through INM not only ensures optimal nutrient supply to maize but also promotes environmental sustainability by minimizing nutrient losses and reducing the risk of pollution [5, 38, 42]. By integrating organic manures, inorganic fertilizers, biofertilizers, and crop residues, along with precision nutrient management, farmers can achieve improved maize productivity and maintain soil fertility in a sustainable manner. While SSNM (site-specific nutrient management) is able to be tailored to the requirements of a site or field, for a broader purpose, INM provides better nutrient management [52].

### **2.8 Conservation agriculture-based practices**

Conservation agriculture (CA) is an approach that promotes sustainable and environmentally friendly maize production while enhancing soil health and crop resilience [7, 15]. Several CA-based practices have proven effective in maize cultivation. One key practice is minimum soil disturbance, which involves reducing or eliminating conventional tillage to preserve soil structure and prevent erosion [53]. Zero tillage, where seeds are directly planted into untilled soil, has shown positive effects on maize yields by improving water infiltration and conserving soil moisture [6, 7]. Another important practice is residue management, where crop residues are left on the soil surface instead of being removed or burned. This practice enhances organic matter content, improves soil fertility, and reduces weed pressure [15]. Cover cropping is also integral to CA in maize systems, where non-commercial crops are grown during fallow periods to protect the soil from erosion, suppress weeds, and improve nutrient cycling [54]. Additionally, crop rotation is a key component of CA, as it breaks disease and pest cycles, improves soil structure, and enhances nutrient availability [55]. Intercropping, the simultaneous cultivation of two or more crops in close proximity, is another beneficial CA practice that optimizes resource use and diversifies farm income [56]. Precision nutrient management, including site-specific fertilization based on soil testing and variable rate application, helps optimize nutrient use efficiency while minimizing environmental impacts. Effective weed management through integrated approaches, such as using cover crops, mechanical methods, and targeted herbicide application, is essential in CA maize production to reduce weed competition. By adopting these CA-based practices, maize producers can achieve sustainable crop production, improve soil health, and mitigate environmental risks [57, 58].

### **2.9 Best practices for nutrient management in maize production**

Implementing best practices for nutrient management is crucial for optimizing maize production and ensuring sustainable crop yields. Firstly, conducting regular soil testing is essential to assess nutrient levels and pH, providing valuable information for fertilizer recommendations [5, 6]. Splitting nitrogen (N) applications throughout the growing season based on crop demand is highly recommended to improve nitrogen use efficiency [25]. For phosphorus (P) fertilization, applying diammonium phosphate (DAP) or triple superphosphate (TSP) at planting time, either broadcast or as a band near the seed, promotes root development and overall plant growth [20]. Potassium (K) fertilizers should be applied either as a pre-plant incorporation or as a side-dress during early crop stages to enhance maize yield and improve drought tolerance. In addition to N, P, and K, secondary nutrients (calcium, magnesium, and sulfur) and micronutrients (zinc, copper, iron, manganese, boron, and molybdenum)

play vital roles in maize production. Soil amendments or foliar applications can be utilized to address deficiencies based on soil test results and crop nutrient requirements [49]. Employing appropriate fertilizer application methods such as broadcasting, banding, side-dressing, or foliar spraying ensures efficient nutrient uptake and minimizes losses [38]. Moreover, adopting conservation practices such as cover cropping, crop rotation, and precision farming techniques can improve nutrient cycling, reduce nutrient runoff, and enhance soil fertility. Multiple studies have linked the impact of biochar on crop productivity to various factors, including enhanced cation exchange capacity (CEC) and the subsequent retention of nutrients, elevated pH levels and increased base saturation, augmented availability of phosphorus, and improved water accessibility for plants [59]. Regular monitoring of crop health and adjusting fertilizer applications based on visual symptoms or plant tissue analysis is crucial to avoid over or under-application of nutrients. By adhering to these best practices, farmers can optimize nutrient management in maize production, leading to increased yields, improved resource use efficiency, and environmental sustainability [60].

### **2.10 Challenges and opportunities for improving nutrient management practices**

Effective nutrient management is essential for sustainable agriculture and maximizing crop productivity, but it faces several challenges and offers opportunities for improvement. One major challenge is the improper use of fertilizers, resulting in nutrient imbalances, environmental pollution, and economic losses [61]. Overapplication of fertilizers can lead to nutrient runoff, causing water pollution and eutrophication [62]. On the other hand, insufficient fertilizer application can result in nutrient deficiencies, limiting crop yields. Another challenge is the lack of soil testing and nutrient analysis, which hinders precise fertilizer recommendations based on the specific nutrient requirements of crops. Inadequate knowledge and awareness among farmers regarding nutrient management practices further contribute to suboptimal fertilizer use [16, 31, 39]. However, there are opportunities for enhancing nutrient management practices. The development and promotion of precision agriculture technologies enable site-specific nutrient application, optimizing fertilizer use efficiency [63]. Integration of organic farming practices, such as cover cropping, crop rotation, and the use of organic amendments, can enhance soil fertility and reduce the reliance on synthetic fertilizers [64]. Additionally, implementing conservation practices like conservation tillage and nutrient management planning can minimize nutrient losses and improve nutrient use efficiency [50]. Education and extension programs play a crucial role in increasing farmers' understanding of nutrient management principles and practices, encouraging adoption of sustainable approaches. Furthermore, research efforts are focused on developing advanced fertilizers with slow-release mechanisms and improved nutrient uptake efficiency. By addressing these challenges and embracing the opportunities, sustainable nutrient management practices can be achieved, promoting environmentally friendly agriculture and ensuring long-term food security [65, 66].
