• Water-soluble fertilisers (WSFs) have emerged as a key agro-innovation to enhance fertiliser use efficiency, restore soil health, and sustain higher yields in fodder crops like maize.
• Traditional fertilisers often lead to uneven nutrient distribution, poor crop response, and environmental harm. In contrast, WSFs provide a balanced nutrient supply, improve soil health, and prevent issues like nitrate accumulation in forage, which can harm livestock. 

Importance of Fertiliser Use Efficiency and Soil Health

• Fertiliser application in fodder production is critical, but it comes with challenges. While increasing biomass and crude protein in maize fodder, nitrogen-heavy fertilisers may result in nitrate accumulation, which can harm livestock.
• Effective fertiliser use ensures balanced nutrient supply, improved crop response, and reduced environmental impacts.
• Indiscriminate fertiliser application can lead to poor crop yields, degradation of soil health, and pollution. 

Field Variability and Nutrient Management Challenges

• Field tests reveal substantial variability in nutrient supply, nutrient use efficiency, and crop responses. Such inconsistencies across fields affect overall fodder productivity.
• To counteract these inefficiencies, precise nutrient and crop management tailored to specific field characteristics is essential.
• Knowledge-intensive approaches to managing soil and fertiliser distribution can significantly improve outcomes in fodder production. 

Role of Water-Soluble Fertilisers (WSFs)

• Water-soluble fertilisers (WSFs) provide a promising solution by offering better nutrient uptake for plants. These fertilisers are fully water-soluble and have a low salt index, making them easy to apply either as foliar sprays or through irrigation.
• Available in various NPK formulations (e.g., 19-19-19), WSFs also contain secondary nutrients like sulphur and zinc.
• They ensure that nutrients remain available to crops without being affected by environmental factors such as leaching, erosion, or evaporation. 

Advantages of WSFs in Maize Fodder Production

• WSFs improve nutrient use efficiency by preventing nutrient wastage. For instance, approximately 25-30% of the recommended fertiliser dose can be saved through WSF use, reducing input costs for farmers.
• These fertilisers do not contribute to salt accumulation in the soil, maintaining soil health over the long term.
• WSFs can be used in a variety of field conditions and provide an efficient, balanced nutrient supply, leading to higher fodder yields and improved nutritional quality of the forage. 

Potential Drawbacks of Water-Soluble Fertilisers

• While WSFs offer several benefits, there is a risk of nutrient overload if they are overapplied or improperly diluted, which can result in phytotoxic injury (plant damage).
• This underlines the need for careful monitoring and management to ensure the correct dosage and application techniques. 

On-Farm Testing and Results

• Field trials conducted by Krishi Vigyan Kendra, Barnala, assessed the effectiveness of WSF (NPK 19-19-19) in maize fodder production. The study compared three fertiliser management practices: farmer’s practice, recommended dose of fertiliser (RDF), and WSF foliar application.
• The trials showed that foliar application of WSF at 1% concentration, combined with 75% RDF, significantly increased maize plant growth (fresh and dry weight) and green fodder yield.
• The nutritional quality of fodder also improved in comparison to traditional practices.

Environmental and Economic Impact

• WSFs reduce leaching, runoff losses of key nutrients (N, P, K), and nitrogen volatilisation, which translates into lower production costs and reduced environmental impact.
• The reduced nutrient wastage and improved efficiency result in lower financial burdens for farmers, particularly in terms of fertiliser costs.

 International Best Practices in the Use of Water-Soluble Fertilisers

• Israel, known for its water-efficient agricultural practices, has pioneered the use of fertigation, which integrates irrigation with fertiliser application. WSFs are dissolved in irrigation water and delivered directly to the root zone through drip irrigation systems.
• Australian farmers combine the use of WSFs with organic and slow-release fertilisers to achieve a balanced nutrient profile.
• Japan has been at the forefront of developing controlled-release WSFs, which allow nutrients to be gradually released over a longer period.
• In Europe, especially in countries like the Netherlands, sustainable agriculture certification schemes encourage the use of WSFs in combination with environmentally-friendly farming practices.

 Road ahead

• Farmers need to be educated about the benefits and proper application methods of water-soluble fertilisers (WSFs).
• Precision farming techniques, such as soil testing and nutrient mapping, should be integrated with the use of WSFs. This ensures that nutrient management is tailored to specific field conditions, reducing wastage and improving crop responses.
• Ongoing research should focus on developing new WSF formulations that cater to various crops and environmental conditions.
• Policies and subsidies that promote the use of eco-friendly and efficient fertilisers like WSFs should be strengthened.
• WSFs should be integrated with other sustainable agricultural practices, such as crop rotation, organic matter incorporation, and water management techniques.

WSFs represent a sustainable and efficient alternative to conventional fertilisers in maize fodder production. They improve fertiliser use efficiency, restore soil health, and ensure higher fodder yields without compromising quality. WSFs offer a balanced, eco-friendly, and cost-effective approach that can help farmers sustain agricultural productivity while mitigating environmental risks.