Composting methods, temperature changes, microbial population and growth of marigold at different compost rates
Composting generally involve the action of heat and microorganisms on organic materials. This study was carried out at the Floriculture garden of National horticultural research institute, Ibadan, to investigate the effect of different methods of composting of the density of microorganism present. Pot and Pit composting methods were used for this experiment. Pot method consisted of using black plastic 300 L pot. Bamboo poles which serve as ventilation pipes were inserted on opposite sides and near the top of the pot; for aeration of the compost by allowing ambient movement of the air in and out of the system. The compost was watered at the onset of composting and when the compost was turned. While the pit was dug to 1 m deep, on a flat ground and covered with tarpaulin. The composting material consisted of cassava peel and poultry manure at ratio 2:1 on dry weight basis. Microbial analysis of compost was determined at intervals; 4, 12 and 24 weeks of composting and this corresponds to mesophilic, thermophilic and curing or maturity stages. From the results, high heat was generated in the pit and pot methods of composting compared with ambient method, with the highest record of 63°C for pit method. At thermophilic stage bacterial cfu g‑1 was significantly (P<0.05) higher (7.4×105 cfu g‑1) compared with fungi population (4.8×105 cfu g‑1). Similar trend was observed at maturity stage where bacteria population was significantly (P<0.05) higher. There was no significant difference in the microbial density of the different composting methods at both mesophillic and maturing stages respectively. However, there was a significant (P<0.05) different in the thermophilic stage with the highest record (9.6×105 cfu g‑1) obtained by pot method. Increased shoot and root dry weights were recorded in plots amended with compost. Compost application at 20.0 t ha‑1 gave the highest plant height, number of leaves and number of branches for marigold plant at 60.92, 62.17 and 12.42 cm, respectively.
Adebayo, A.G., Oyedeji, E.O., Akintoye, H.A., Shokalu, A.O., Olatunji, M.T., Akintola, O.A., James, I.E., Elum, C.G. and Fade-aluko, A.A. (2021). Composting methods, temperature changes, microbial population and growth of marigold at different compost rates. Acta Hortic. 1305, 279-284
compost, organic farming, microorganisms, composting methods, marigold