The Effect of Selected Commercial Organic Fertilizers on the Growth and Yield of Bush Beans in Central Uganda
Author: TUGUME ESAU
Supervisor: John Byalebeka
A study to assess the effect of selected commercial organic fertilizers on the market in Uganda and local farmyard manure in increasing growth and yield of bush beans (Phaseolus vulgaris) was conducted for two seasons at Kabanyolo and Nkozi in central Uganda. First of all, a survey was conducted in Container village in Kampala to establish the different types of organic fertilizers sold in the market and their prices. Then four (two solid: Biochar and Fertiplus and two liquid: Biogrow and Digrow) organic fertilizers on the market were selected for the study. Local farmyard manure was added for comparison purpose. Therefore the study had six treatments; namely: the four selected commercial organic fertilizers, local farmyard manure and a control. Samples of the four organic fertilizers and the local farmyard manure were taken to the laboratory for analysis to establish their nutrient contents. Field trials to assess the performance of the selected commercial organic fertilizers and local farmyard manure on bush beans were conducted at two locations for two seasons using a randomized complete block design and four replicates. Data was collected on plant fresh and dry weights at 40 days after planting and on biomass and grain yield at harvest. Finally, data was analyzed using GenStat 14 Edition. Results from market study showed that there were ten different types of organic fertilizers on the market in Container village in Kampala. Out of those ten organic fertilizers on the market only one, Biogrow, was most dominant, taking up 52.5% of the market. It was established that this organic fertilizer was locally produced and its price was relatively low compared to the others. It was also established that the organic fertilizer market in Container village was heavily dominated, (82%), by liquid fertilizers. Laboratory analysis of the selected organic fertilizers, revealed large variances between nutrient content reported by manufacturers and the laboratory results, especially for Biogrow. For the field trials, Biochar treatment significantly (P=0.043) increased mean fresh weight of bush beans compared other treatments and control in season 1(2017) but wasnít consistent in season 2(2018). All organic fertilizers didnít consistently significantly increase mean fresh weight, dry weight, plant biomass and yield of bush beans. Bush beans didnít significantly respond to organic fertilizer treatments and therefore a need to conduct future experimental trials in more successive growing seasons on bush beans or with other crops that can effectively respond to organic fertilizer amendments.