Abstract:
Soil and soil nutrient degradation is a substantial problem in Uganda. It is estimated that 4% - 12% of GNP is lost from environmental degradation, 85% of this from soil erosion, nutrient loss and changes in crops. The use of bio fertilizers is picking as a sustainable approach to soil nutrient management for different crop production. This study therefore assessed the effect of bio-fertilizer in increasing productivity and reducing production costs of Narosorg 2 sorghum variety in Uganda. Bio fertilizers from green gram and pigeon extracts were applied at different levels of 100 mls, 75 mls, 50 mls, and Urea applied in farmers practice and a control and split plot experimental design was used. The bio fertilizers were applied at an interval of two weeks until flowering and the urea fertilizer was applied once two weeks after germination as practiced by the farmers. The results of the study showed that different rates of bio fertilizers significantly (p<0.05) affected different growth and yield parameters of Narosorg 2 sorghum variety. 100 mls of bio-fertilizers produced significantly the highest plant height, leaf area and leaves numbers and followed by Urea application at 5g, and 50mls of bio fertilizer respectively.
Meanwhile the application of 100 mls of bio fertilizers produced the highest yield which is about 3075 kg/ ha and followed by Urea application which produced about 2988 kg/ha. All the different levels of the bio fertilizers performed significantly higher than control in terms of yields in kg/ha. This study concludes that the best level of application to yield the best result in terms of growth and yields in kg/ha is 100 mls of bio fertilizers/20liters of water applied, followed by Urea application and 70 mls respectively at application of rate of two weeks’ interval. However, more study needs to be done on the qualitative analysis of the bio fertilizers to establish the standard nutrients available so as it can be recommended appropriately for use in different crops as well. More study should as well be conducted on the use of these bio fertilizers as a blend with inorganic fertilizers for improved crop production and productivity.
Further studies be done on more varied levels of the bio fertilizers preferably increased levels than those used in this research and as well studies be done on the bio fertilizer effect on various crops especially vegetables
