Recycling

Biography

Biography: Nurlidia Mansor

Abstract

Statement of the Problem: Urea fertilizer is one of the most used form of fertilizer worldwide. Upon application to soil however, up to 60% will be lost to the environment via ammonia volatilization. Apart from contributing to greenhouse gasses, this phenomena reduces the efficiency of urea fertilizers as well depletes nutrient availability for plant uptake. The introduction of urease inhibitors or fertilizer additives was able to address this problem and some commercially available products claims to be able to reduce volatilization of up to 70% for a certain period of time. Nevertheless, current urease inhibitors available in the market have been shown to cause plant stress such as leaf-tip scorch, chlorosis and necrosis. The toxicity towards certain type of plants and in some reports causes side effect to users has also raised safety concerns. Therefore, a non-chemical based source of inhibitor is needed to address this issue. Studies on natural based inhibitors have found positive potential in inhibiting ammonia volatilization by blocking the site of the urease enzyme and thus temporarily inhibiting the reaction. During the inhibition period, urea fertilizer are able to travel deeper into the soil while maintaining its nutrient content until the inhibition period ends. Within the soil matrix, urea is able to be disperse efficiently as N source to plants once the inhibitory effect ends. Some studies have reported active inhibitory compounds within several natural products such as neem, garlic, cabbage, guava and others. However, these studies focused on the application in pharmaceutical studies. In agriculture, the inhibitory potential of natural based products is still lacking in information. Thus, this study looks into the potential of using agriculture waste from guava plantation with active inhibitory compounds to be used for the purpose of urea fertilizer enhancement. Methodology & Theoretical Orientation: Extraction of active compounds from guava agriculture waste will be conducted to analyze its inhibitory potential as well as to determine its minimum inhibitory concentration. Urea activity in soil will be measured to determine the inhibitory reaction of the natural based inhibitor with soil urease. Natural-based inhibitors will be compared with chemical-based inhibitors in its trending to determine the potential for soil urease application. Findings: The study found that the extract from agriculture waste showed potential of inhibition towards soil urease although the level of inhibition is lower than the chemical-based inhibitor. Nevertheless, the natural based inhibitors showed improved inhibition compared to the controlled samples indicating reduction in ammonia volatilization. Conclusion & Significance: The study shows the potential of guava based agricultural waste in producing the source of inhibition for potential use as fertilizer enhancers. Recommendations: It is recommended to look into the mechanism of inhibition for the natural-based inhibitor in order to understand its application in soil.