Author(s)

Madushan Dhammika Gunarathna^1*, Ashan Sithija Wickramaarachchi¹, Polegodage Dilushi Sureka Ruwan Kumari², Hiti Mudiyanselage Sithara Dilrukshi Wijekoon³, Deeyagahage Sujeewa Mallik de Silva¹

¹Department of Chemistry, Faculty of Science, University of Kelaniya, Kelaniya, Sri Lanka.
²Department of Microbiology, Faculty of Science, University of Kelaniya, Kelaniya, Sri Lanka.
³Department of Statistics and Computer Science, University of Kelaniya, Kelaniya, Sri Lanka.

This study investigates the nitrogen (N), phosphorous (P), and potassium (K) contents in raw biomasses of Camellia sinensis, Gliricidia sepium, and Musa acuminata. Therein, the highest N and P content was seen in Camellia sinensis 116.80 ± 0.08 mg and 66.00 ± 0.14 mg respectively. The highest K content (106.80 ± 0.04 mg) was observed in Musa acuminata. Next, all three types of plant materials were allowed to decompose in water for 3 weeks, and a sample from each was analyzed for NPK after the 1st, 2nd, and 3rd week during decomposition. A significant increase in the release of N, P, and K by the Camellia sinensis to water (P < 0.05) was observed during the decay. However, the release of K by Gliricidia sepium and N by Musa acuminate were not significantly changed (P > 0.05) over time. The ratio for N:P:K was calculated for raw biomass samples and decomposed samples to find the best fitting N:P:K ratio to apply to young tea plants as organic fertilizers. In addition to that, the microbial insight of these organic compounds was analyzed by observing how microbial population increased with decomposition by the enumeration of the total microbial count. A considerable increment in total microbial count was observed up to 3.28 × 10⁶, 1.21 × 10¹⁰, 2.18 × 10⁸, and 6.49 × 10⁷ CFU/ml for Camellia sinensis, Gliricidia sepium, Musa accuminata (leaves), and Musa accuminata (trunk) respectively. The presence of phosphate solubilizing bacteria (PSB) and nitrogen solubilizing bacteria (NSB) throughout the decomposition period was confirmed by their growth on NBRIP and a modified nutrient medium that was specifically designed for the identification of ammonifiers respectively. Prepared fertilizer samples were applied to young tea plants that were grown in the Mawanella area in Sri Lanka (7°15'12.42"N 80°26'47.62"E) and according to the results, it is clear that fertilizer mixture 1 (N:P:K, 10:5:10, tea dust + Gliricidia + banana trunk) and fertilizer mixture 2 (N:P:K, 10:5:10, tea dust + Gliricidia + banana leaves) has the potential to increase the growth of young tea plants.

Camellia sinensis, Musa accuminata, Gliricidia sepium, Phosphate Solubilizing Bacteria, Nitrogen Solubilizing Bacteria

Gunarathna, M. , Wickramaarachchi, A. , Kumari, P. , Wijekoon, H. and de Silva, D. (2024) Analysis of NPK in Camellia sinensis, Gliricidia sepium, and Musa acuminata Biomasses for Preparation of an Organic Fertilizers Formula for Young Tea Plants (Musa acuminata) and Studying of Their Nutrient Release Capacity in the Biodegradation Process. Journal of Agricultural Chemistry and Environment, 13, 115-132. doi: 10.4236/jacen.2024.131008.