Effects of chemical and organic fertilizer treatments on bacterial populations and diversity from selected maize fields in Lusaka province.
| dc.contributor.author | Lubasi, Namasiku | |
| dc.date.accessioned | 2025-05-29T14:47:54Z | |
| dc.date.available | 2025-05-29T14:47:54Z | |
| dc.date.issued | 2024 | |
| dc.description | Thesis of Master of Science Degree in Applied Microbiology. | |
| dc.description.abstract | Microbes are the primary agents responsible for the biogeochemical cycling of nutrients, promoting plant development, and suppressing disease. However, not much is known about how chemical fertilizers affect the populations, distribution and survival of soil microorganisms which are essential for enhancing soil structure in soils. To gain a better understanding of the effects of chemical fertilizers on bacterial community diversity, soil samples were collected from 20 representative locations in Lusaka Province of Zambia to investigate how soil bacterial diversity is shaped following the application of chemical (compound D) and organic (manure) fertilizers. The sampling was done between May to June after farming season. Soil physicochemical properties were analyzed. Genomic DNA was extracted from purified sub-cultured bacteria using Qiagen DNA extraction kit and PCR amplified using 16S rRNA primers and amplicons were sequenced. Analysis of variance (ANOVA) was carried out using Minitab (version 17.1.0.0) and a phylogenic tree was generated in MEGA 11. Little variation was recorded in soil temperature which ranged between 29 – 32˚C and the only exception was in soil temperatures of samples collected from the eastern farms (East 1 – East 5) for both organically and chemically fertilized maize fields. The pH of chemically fertilized soils ranged from 4.9 – 6.78 while organically fertilized soils had higher pH ranging from 6.77 – 7.05. The ANOVA test showed that variance in the soil moisture content and organic matter significantly affected and shaped the bacterial communities of the soils. The isolated soil bacteria were predominantly Gram-positive. The colonies mainly composed of bacteria with bacillus and cocci cell shape. Oligotrophic bacteria dominated in chemically fertilized soils. Different fertilization treatments had different impacts on the soil bacterial communities. Chemically fertilized soils had metabolic and stress-resistant bacteria including Exiguobacterium auratiacum, Gottfriedia acidiceleris, Mycrobacterium paludicola, Lysinibacillus fusiformis and Peribacillus frigoritolerans capable of metabolizing polysaccharides and proteins. Soils to which organic fertilizers were applied had copiotrophic bacteria including Actinobacteria and Arthrobacter capable of degrading unusual polymeric compounds. Therefore, it is important to understand the dynamics of chemical and organic fertilizers on soil bacteria to help devise agricultural practices that maintain soil health and fertility as well as maintain good crop yields. Keywords: Bacterial diversity, chemical fertilizer, organic fertilizer, oligotrophic, copiotrophic. | |
| dc.identifier.uri | https://dspace.unza.zm/handle/123456789/9170 | |
| dc.language.iso | en | |
| dc.publisher | The University of Zambia | |
| dc.title | Effects of chemical and organic fertilizer treatments on bacterial populations and diversity from selected maize fields in Lusaka province. | |
| dc.type | Thesis |