Integration of rhizobacteria consortium with reduced mineral fertilizer rates enhances yield of Irish potato (Solanum tuberosum) under screenhouse conditions
Paper Details
Integration of rhizobacteria consortium with reduced mineral fertilizer rates enhances yield of Irish potato (Solanum tuberosum) under screenhouse conditions
Abstract
Irish potato (Solanum tuberosum) is an important food and cash crop for smallholder farmers in Tanzania, but its high nutrient demand often encourages excessive mineral fertilizer use, increasing production costs and risks of environmental pollution. This study evaluated whether rhizobacteria consortia integrated with reduced mineral fertilizer rates could maintain or improve Irish potato productivity and provide a basis for more sustainable nutrient management. Rhizobacteria were isolated from potato rhizosphere soils collected from Njombe, Mbeya, and Kilimanjaro regions. Isolates were screened for nitrogen fixation and potassium solubilization, and five promising isolates were assessed for compatibility and used to formulate ten two-strain consortia. A screenhouse experiment comprising 22 treatments was conducted in a completely randomized design with three replications, comparing the consortia alone and in combination with 50% of the recommended mineral fertilizer rates against unfertilized and fully fertilized controls. All five selected isolates were mutually compatible. Treatment T21, comprising isolates Rh-022 and Rh-024 with 50% mineral fertilizer, produced the highest fresh tuber weight (412.6 g) and number of tubers (27.33), compared with 14.2 g and 1.67 tubers in the unfertilized control, respectively. The highest total dry matter yield (161.96 g) was recorded in T18, while T21 produced 155.22 g. Overall, integrating compatible rhizobacteria consortia with half the recommended mineral fertilizer rate enhanced potato yield and showed potential to reduce dependence on mineral fertilizers while sustaining crop productivity.
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Ikunda Herman Massawe*, Akida Meya, Ernest Mbega, 2026. Integration of rhizobacteria consortium with reduced mineral fertilizer rates enhances yield of Irish potato (Solanum tuberosum) under screenhouse conditions. Int. J. Agron. Agric. Res., 29(1), 1-9.
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