On Farm Evaluation of Introduced Rhizobia Strains On Growth and Development of Groundnuts in Uganda.

Legume Biological Nitrogen Fixation (BNF) offers an especially attractive alternative to fossil fuel-derived N fertilizers in subsistence farming and sustainable agricultural programs in developing countries where access to fertilizer N is expensive and hardly available to small scale farmers. The yield performance of Ugandan groundnut varieties inoculated with different strains of rhizobia was investigated in three different experiments. In 2011, two groundnut varieties (Serenut 2 and Serenut 3) were evaluated in 5 inoculation treatments (strain Lift, strain First, strain Vault and strain Muk and control no inoculation on their ability to nodulate test plants. The experiments were potted and two different soil media were used (sterilized or unsterilized soil) under completely randomized block design replicated 3 times giving a total of 60 experimental units with controlled watering in a screen house at National Crops Resources Research Institute (NaCRRI). In 2011-2012, six inoculant treatments (strains Lift, Muk, Vault and Histick, fertilizer Urea and control no inoculation) tested with three varieties including two from the first experiment (Serenut 2, Serenut 3 and Acholi white) under split-plot randomized complete block design, replicated three times giving a total of 54 experimental plots. These were used to determine their effectiveness and competitiveness in the field under rain fed conditions at Makerere University Agricultural Research Institute (MUARIK). In 2012-2013, to further investigate the performance of three inoculation treatments (strains Lift, Vault, Histick and control no inoculation) under different ecological zones, on-farm experiments were set in different groundnut growing areas (Wakiso, Jinja and Kabarole) under completely randomized block design replicated four times giving a total of 48 experimental plots in Uganda.