In an effort to address the persistent challenge of low soybean production in Indonesia, particularly on less fertile coastal sandy lands, a recent study by Hariyono, A.R Putra, Mulyono, and B.H. Isnawan, published in the Asian Journal of Applied Research for Community Development and Empowerment, investigated the efficacy of nano biochar-coated urea as a slow-release nitrogen fertilizer. Their findings offer a promising solution to enhance soybean growth and yield, contributing to global food security and sustainable agricultural practices.

Soybeans are a crucial food commodity, ranking third in importance after rice and maize, yet Indonesia faces a significant deficit in meeting its domestic demand. Coastal sandy soils, characterized by high porosityPorosity of biochar is a key factor in its effectiveness as a soil amendment and its ability to retain water and nutrients. Biochar’s porosity is influenced by feedstock type and pyrolysis temperature, and it plays a crucial role in microbial activity and overall soil health. Biochar More, low water retention, and limited nutrient-holding capacity, pose a considerable challenge for cultivation. The conventional urea fertilizer, known for its hygroscopic and volatile nature, often leads to substantial nitrogen loss through leachingLeaching is the process where nutrients are dissolved and carried away from the soil by water. This can lead to nutrient depletion and environmental pollution. Biochar can help reduce leaching by improving nutrient retention in the soil.   More in such soils, reducing its effectiveness. This research aimed to mitigate these issues by employing nano biocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More, a material capable of enhancing surface area and reactivity at the nanometer scale.

The study, conducted in a greenhouse at Muhammadiyah University of Yogyakarta, utilized a single-factor experimental design with six treatments, each replicated three times with six plant samples. The treatments included different forms of urea (Prill, Granules, and Tablet), both uncoated and coated with nano biochar derived from coconut shells. The coconut shell nano biochar was prepared by anaerobically burning coconut shells, grinding them into powder, and then processing them with a ball mill to achieve an average particle size of 53.307 nm, with 95% of particles ranging from 20 nm to 100 nm. This nano biochar was then blended with urea in a 1:6 ratio and applied at 30, 20, and 10 days after planting.

The results demonstrated a significant positive impact of the nano biochar coating on soybean growth and yield. Notably, the nano biochar-coated urea prill treatment (Treatment B) significantly outperformed other treatments, especially the uncoated urea prill (Treatment A).

For plant growth parameters, while plant height and leaf chlorophyll content showed no statistically significant difference across all treatments, notable improvements were observed in leaf number and leaf area. Specifically, nano biochar-coated urea prill led to superior vegetative growth by effectively delivering nitrogen nutrients, which are crucial for leaf development and overall plant height. The coating reduced nitrogen leaching, improving fertilizer use efficiency and ensuring a more stable supply of nutrients to the plants. This enhanced nutrient availability supports accelerated growth, increased protein production, and greater chlorophyll synthesis, leading to greener leaves and a higher leaf count.

In terms of yield parameters, the nano biochar-coated urea prill treatment (Treatment B) significantly enhanced the number of pods, fresh weight of pods, dry weight of pods, and dry weight of seeds compared to the uncoated urea prill (Treatment A). The dry weight of pods, reflecting the efficiency of capturing solar energy and utilizing it for photosynthesis, showed a substantial increase. The highest dry weight of seeds, a critical indicator of soybean yield success, was achieved with the nano biochar-coated urea prill, demonstrating a 133% increase from 8.58 g (Treatment A) to 19.97 g (Treatment B). This improvement is attributed to the sustained release of nitrogen, which ensures sufficient nutrient supply during critical growth phases, including seed filling.

The study concludes that coating urea prill with coconut shell nano biochar significantly improves soybean growth and yield in coastal sandy soil. This innovative approach can enhance urea’s effectiveness and boost soybean productivity, providing a sustainable solution for agricultural intensification on marginal lands and contributing to Indonesia’s food security goals.

Source: Hariyono, Putra, A. R., Mulyono, & Isnawan, B. H. (2025). The Efficacy of Nano Biochar Coated Urea in Enhancing Soybean Growth and Yield. Asian Journal of Applied Research for Community Development and Empowerment, 9(2).