1. Influence of Minjingu rock phosphate on biological nitrogen fixation and performance of Lupin (Lupinus albus) in Kabete, Kenya

2. Minjingu rock phosphate (MRP) could be a viable option to the expensive phosphatic fertilizers but its solubility is low. The challenge therefore is to develop technologies that will accelerate P release from the MRP for enhanced soil fertility and crop yields. It is envisaged that the use of lupin will boost the solubility

3. of rock phosphate and in-turn its biological Nitrogen fixation (BNF) and performance of lupin. A completely randomized design will be used to evaluate the influence of lupin on MRP solubilization. MRP will be applied at the rates of; 0kg ha -1, 30kg ha -1, 60kg ha -1 and 90kg ha -1 and mixed with 2kg of soil and

4. placed in pots on which lupin will be grown. Wheat to be used as a reference crop to aid in the determination of BNF in lupin will similarly be treated. Soil will be sampled prior to planting and at harvest and analyzed for P, N and pH levels using standard laboratory analytical procedures. Plants will be

5. sampled at harvest and similarly analyzed for N and P. Application of MRP on lupin will have a synergetic effect in which the solubility of MRP will be enhanced and concomitantly its BNF and yield enhanced.

6. Key words: Biological Nitrogen fixation; Minjingu rock phosphate; Lupin; Reference crop