In the rice-wheat cropping systems of Northwestern Pakistan, efficient nitrogen (N) management is crucial for boosting productivity and sustaining soil health. Overuse of chemical fertilizers, especially urea, has become common, often delivering high short-term yields at the cost of long-term soil fertility. A recent multi-year study sheds light on how integrating organic and inorganic N sources can transform this system, benefiting farmers and the environment alike.

Key Findings from the Study

1. Sole Urea Application:
Urea alone produced the highest rice yields and growth parameters (e.g., plant height, leaf area index, and number of panicles per plant). However, it led to the lowest residual soil nitrogen after harvest, negatively affecting the subsequent wheat crop's growth and yield.

2. Organic Sources Alone:
Using only organic sources—particularly poultry manure (PM)—significantly enhanced soil fertility and positively impacted wheat yield. PM improved biological and grain yields, nitrogen content in rice grains and straw, and post-harvest soil nitrogen levels.

3. Combined Application (50:50 Ratio):
The most effective and sustainable approach was combining organic and inorganic N sources in a 50:50 ratio. This integration enhanced rice and wheat yields, improved soil health, and increased profitability. Notably, the PM + urea combination yielded the highest profits—up to PKR 355,000 for rice and PKR 38,000 for wheat.

4. Animal Manures vs. Crop Residues:
Animal manures outperformed crop residues in boosting yield, retaining soil nitrogen, and generating higher returns. Wheat straw had the least impact on yield and soil fertility among all treatments.

5. Yearly Improvements:
Improvements were more pronounced in the second year, with increased soil nitrogen and higher crop yields, underscoring the cumulative benefits of sustained organic input use.

Recommendations

• Integrate Organic and Inorganic Fertilizers:
Adopt a balanced 50:50 mix of organic (especially animal manures) and inorganic fertilizers for higher yields and sustainable soil health.

• Avoid Sole Urea Application:
Relying exclusively on urea can degrade soil fertility over time and should be avoided for long-term sustainability.

• Prefer Animal Manures:
Among organic options, poultry manure delivered the best results and should be prioritized when blending with urea.

• Plan for Long-Term Soil Fertility:
Continued use of organic matter not only supports current crop performance but also builds soil resilience over time.

Practical Implications for Stakeholders

For Farmers:

• Adopt integrated nutrient management using poultry manure and urea to boost both rice and wheat productivity.

• A 50:50 blend ensures optimal yield, profitability, and soil conservation.

• Leverage locally available poultry manure, especially for smallholder farmers.

For Policy Makers:

• Formulate region-specific nutrient management recommendations.

• Subsidize and promote composted animal manures to lessen dependence on chemical fertilizers.

• Facilitate public-private initiatives for composting and organic waste utilization.

For Extension Services and Development Agencies:

• Educate farmers on integrated practices through demonstrations, farmer field schools, and mass media.

• Promote the year-round benefits of organic inputs for sustainable fertility management.

• Build farmer capacity in composting, manure handling, and the economic benefits of smarter N use.

This research underscores that smarter, integrated nitrogen management is not just about feeding crops—it's about feeding the soil and securing the future of Pakistan’s rice-wheat belt.