Effect of Temperature Changes on the Bacterial and Fungal Succession Patterns during Composting of Some Organic Wastes in Greenhouse

Aim: Organic wastes were composted and the effect of temperature changes on the bacterial and fungal succession patterns studied.

Study Design: The wastes which included cow dung (CD), pig waste (PW), poultry litter (PL) and source-separated municipal solid waste (MSW) and their combinations: PL+MSW, PW+MSW and CD+MSW were allowed to decompose for 70 days in a greenhouse.

Place and Duration of Study: This study was carried out between September 2017 and January 2018, in the greenhouse of the Agricultural Research Farm of Federal University of Technology, Owerri, Nigeria.

Methodology: The wastes were allowed to decompose for 70 days in a greenhouse using the modified windrow method of composting. Standard microbiological methods were used to monitor temperature changes in compost piles as well as changes in bacterial and fungal populations.

Results: Results revealed that changes in temperature affected microbial composition in the compost piles. The highest temperature recorded was 60oC for cow dung (CD) compost pile while at maturity the temperature in all the compost piles ranged between 27°C to 30°C. Different bacterial and fungal populations were isolated during the thermophilic and mesophilc phases of composting. Bacteria isolates included species of Staphylococcus, Proteus, Klebsiella, Salmonella, Alcaligenes, Serratia, Lactobacillus and Pseudomonas. Others included Enterobacter, Bacillus, Streptococcus, Corynebacterium and Micrococcus spp. Fungal species isolated included Candida, Saccharomyces, Rhizopus, Aspergillus, Mucor and Fusarium.

Conclusion: The presence of some plant growth promoting (PGP) bacteria at the end of composting qualifies organic waste composts as effective nutrient sources for crop production and can be considered as potential alternatives to chemical fertilizers.