Nutrient content of super liquid fertilizer (SLF) from dairy sludge waste and the potential as a biopesticide

Purpose The current use of pesticides and chemical fertilizers harms the environment, alternative substitutions using organic materials are needed. One of them is utilizing the dairy industry sludge waste to become a Super Liquid Fertilizer (SLF). This study aimed to analyze the nutrient quality of SLF (a dairy industry sludge waste that was added to some the microbial activators).Method The types of microbes and the number of nutrients in pure sludge were identified, followed by composed SLF and applied to the larvae of Spodoptera litura to see the pathogenicity. Data were analyzed using SPSS.26 software.Results The types of microbes that exist in the pure sludge waste of the dairy industry are dominated by Pseudomonas bacteria, as much as 50%. The nutrient content of SLF is appropriate to Indonesia’s national standard for liquid organic fertilizer. Analysis of varian (ANOVA) analysis shows that the addition of activator microbe at P3 is the best. The number of microbes in SLF is significantly different (P lt; 0.05) at each treatment, where P3 is the best treatment. The pathogenicity of SLF is also good, as evidenced by the motility of the Spodoptera litura reaching 98% in the P5 treatment for 96 hours.Conclusion This research has succeeded in producing SLF with the nutritional value of nutrients that are close to the Indonesian Ministry of Agriculture. The number of bacterial colonies in SLF is more than 106 CFU/mL, especially in the P3 treatment. SLF can kill Spodoptera litura caterpillars in a time period of 46 hours.