Impact of Fertilizer and Irrigation Treatments on the Rhizosphere Microbiome of Collard Green (Brassica oleracea L. var. acephala).

In recent years, the study of plant microbiome has gained substantial attention because it influences both plant health and productivity. The study of the interactions between plants and their microbial communities especially in the rhizosphere is important for developing sustainable agricultural practices. Researchers have often been engaged in demonstrating the impacts of both organic and chemical fertilizers in terms of nutrient availability and the long-term effects on soil, plants, and the environment. A field experiment will be conducted to evaluate the effect of fertilizer regimes and irrigation practices on bacterial and fungal community composition and structure as well as on biochemical activities in the rhizosphere of collard greens (Brassica oleracea var. acephala). Experimental design will be a split plot design in which three different fertilizer regimes (organic fertilizer- Mighty Grow (4-2-4); Inorganic fertilizer- NPK (13-13-13) and a mixture of organic and inorganic fertilizer) will be arranged into 2 irrigation treatments (with irrigation and without irrigation) with 4 replications. Rhizosphere soil samples will be collected at harvest, with DNA being extracted from each soil sample for downstream microbial and biochemical analysis to assess the ecology of the rhizosphere under each treatment. Statistical analysis will be provided using SAS statistical suite. It is expected that the treatment with mixed fertilizer plus irrigation will increase the soil microbial richness and microbial diversity (Bacterial and Fungi) and as well alter the biochemical activities in the rhizosphere of collard greens.